auto removed a bunch of unused local variables

( removed with a script parsing compiler output )



git-svn-id: svn://svn.code.sf.net/p/ultrastardx/svn/trunk@950 b956fd51-792f-4845-bead-9b4dfca2ff2c

1 files changed, 4361 insertions, 4361 deletions

diff --git a/Game/Code/lib/JEDI-SDL/SDL/Pas/sdlutils.pas b/Game/Code/lib/JEDI-SDL/SDL/Pas/sdlutils.pas
index b15fa9ba..3941814d 100644
--- a/Game/Code/lib/JEDI-SDL/SDL/Pas/sdlutils.pas
+++ b/Game/Code/lib/JEDI-SDL/SDL/Pas/sdlutils.pas
@@ -1,4361 +1,4361 @@
-unit sdlutils;

-{

-  $Id: sdlutils.pas,v 1.5 2006/11/19 18:56:44 savage Exp $

-

-}

-{******************************************************************************}

-{                                                                              }

-{       Borland Delphi SDL - Simple DirectMedia Layer                          }

-{                SDL Utility functions                                         }

-{                                                                              }

-{                                                                              }

-{ The initial developer of this Pascal code was :                              }

-{ Tom Jones <tigertomjones@gmx.de>                                             }

-{                                                                              }

-{ Portions created by Tom Jones are                                            }

-{ Copyright (C) 2000 - 2001 Tom Jones.                                         }

-{                                                                              }

-{                                                                              }

-{ Contributor(s)                                                               }

-{ --------------                                                               }

-{ Dominique Louis <Dominique@SavageSoftware.com.au>                            }

-{ Róbert Kisnémeth <mikrobi@freemail.hu>                                       }

-{                                                                              }

-{ Obtained through:                                                            }

-{ Joint Endeavour of Delphi Innovators ( Project JEDI )                        }

-{                                                                              }

-{ You may retrieve the latest version of this file at the Project              }

-{ JEDI home page, located at http://delphi-jedi.org                            }

-{                                                                              }

-{ The contents of this file are used with permission, subject to               }

-{ the Mozilla Public License Version 1.1 (the "License"); you may              }

-{ not use this file except in compliance with the License. You may             }

-{ obtain a copy of the License at                                              }

-{ http://www.mozilla.org/MPL/MPL-1.1.html                                      }

-{                                                                              }

-{ Software distributed under the License is distributed on an                  }

-{ "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or               }

-{ implied. See the License for the specific language governing                 }

-{ rights and limitations under the License.                                    }

-{                                                                              }

-{ Description                                                                  }

-{ -----------                                                                  }

-{   Helper functions...                                                        }

-{                                                                              }

-{                                                                              }

-{ Requires                                                                     }

-{ --------                                                                     }

-{   SDL.dll on Windows platforms                                               }

-{   libSDL-1.1.so.0 on Linux platform                                          }

-{                                                                              }

-{ Programming Notes                                                            }

-{ -----------------                                                            }

-{                                                                              }

-{                                                                              }

-{                                                                              }

-{                                                                              }

-{ Revision History                                                             }

-{ ----------------                                                             }

-{               2000 - TJ : Initial creation                                   }

-{                                                                              }

-{   July   13   2001 - DL : Added PutPixel and GetPixel routines.              }

-{                                                                              }

-{   Sept   14   2001 - RK : Added flipping routines.                           }

-{                                                                              }

-{   Sept   19   2001 - RK : Added PutPixel & line drawing & blitting with ADD  }

-{                           effect. Fixed a bug in SDL_PutPixel & SDL_GetPixel }

-{                           Added PSDLRect()                                   }

-{   Sept   22   2001 - DL : Removed need for Windows.pas by defining types here}

-{                           Also removed by poor attempt or a dialog box       }

-{                                                                              }

-{   Sept   25   2001 - RK : Added PixelTest, NewPutPixel, SubPixel, SubLine,   }

-{                           SubSurface, MonoSurface & TexturedSurface          }

-{                                                                              }

-{   Sept   26   2001 - DL : Made change so that it refers to native Pascal     }

-{                           types rather that Windows types. This makes it more}

-{                           portable to Linix.                                 }

-{                                                                              }

-{   Sept   27   2001 - RK : SDLUtils now can be compiled with FreePascal       }

-{                                                                              }

-{   Oct    27   2001 - JF : Added ScrollY function                             }

-{                                                                              }

-{   Jan    21   2002 - RK : Added SDL_ZoomSurface and SDL_WarpSurface          }

-{                                                                              }

-{   Mar    28   2002 - JF : Added SDL_RotateSurface                            }

-{                                                                              }

-{   May    13   2002 - RK : Improved SDL_FillRectAdd & SDL_FillRectSub         }

-{                                                                              }

-{   May    27   2002 - YS : GradientFillRect function                          }

-{                                                                              }

-{   May    30   2002 - RK : Added SDL_2xBlit, SDL_Scanline2xBlit               }

-{                           & SDL_50Scanline2xBlit                             }

-{                                                                              }

-{  June    12   2002 - RK : Added SDL_PixelTestSurfaceVsRect                   }

-{                                                                              }

-{  June    12   2002 - JF : Updated SDL_PixelTestSurfaceVsRect                 }

-{                                                                              }

-{ November  9   2002 - JF : Added Jason's boolean Surface functions            }

-{                                                                              }

-{ December 10   2002 - DE : Added Dean's SDL_ClipLine function                 }

-{                                                                              }

-{    April 26   2003 - SS : Incorporated JF's changes to SDL_ClipLine          }

-{                           Fixed SDL_ClipLine bug for non-zero cliprect x, y  }

-{                           Added overloaded SDL_DrawLine for dashed lines     }

-{                                                                              }

-{******************************************************************************}

-{

-  $Log: sdlutils.pas,v $

-  Revision 1.5  2006/11/19 18:56:44  savage

-  Removed Hints and Warnings.

-

-  Revision 1.4  2004/06/02 19:38:53  savage

-  Changes to SDL_GradientFillRect as suggested by

-  Ángel Eduardo García Hernández.  Many thanks.

-

-  Revision 1.3  2004/05/29 23:11:54  savage

-  Changes to SDL_ScaleSurfaceRect as suggested by

-  Ángel Eduardo García Hernández to fix a colour issue with the function. Many thanks.

-

-  Revision 1.2  2004/02/14 00:23:39  savage

-  As UNIX is defined in jedi-sdl.inc this will be used to check linux compatability as well. Units have been changed to reflect this change.

-

-  Revision 1.1  2004/02/05 00:08:20  savage

-  Module 1.0 release

-

-

-}

-

-interface

-

-{$I jedi-sdl.inc}

-

-uses

-{$IFDEF UNIX}

-  Types,

-  Xlib,

-{$ENDIF}

-  SysUtils,

-  sdl;

-

-type

-  TGradientStyle = ( gsHorizontal, gsVertical );

-

-// Pixel procedures

-function SDL_PixelTest( SrcSurface1 : PSDL_Surface; SrcRect1 : PSDL_Rect; SrcSurface2 :

-  PSDL_Surface; SrcRect2 : PSDL_Rect; Left1, Top1, Left2, Top2 : integer ) : Boolean;

-

-function SDL_GetPixel( SrcSurface : PSDL_Surface; x : integer; y : integer ) : Uint32;

-

-procedure SDL_PutPixel( DstSurface : PSDL_Surface; x : integer; y : integer; pixel :

-  Uint32 );

-

-procedure SDL_AddPixel( DstSurface : PSDL_Surface; x : cardinal; y : cardinal; Color :

-  cardinal );

-

-procedure SDL_SubPixel( DstSurface : PSDL_Surface; x : cardinal; y : cardinal; Color :

-  cardinal );

-

-// Line procedures

-procedure SDL_DrawLine( DstSurface : PSDL_Surface; x1, y1, x2, y2 : integer; Color :

-  cardinal ); overload;

-

-procedure SDL_DrawLine( DstSurface : PSDL_Surface; x1, y1, x2, y2 : integer; Color :

-  cardinal; DashLength, DashSpace : byte ); overload;

-

-procedure SDL_AddLine( DstSurface : PSDL_Surface; x1, y1, x2, y2 : integer; Color :

-  cardinal );

-

-procedure SDL_SubLine( DstSurface : PSDL_Surface; x1, y1, x2, y2 : integer; Color :

-  cardinal );

-

-// Surface procedures

-procedure SDL_AddSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;

-  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );

-

-procedure SDL_SubSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;

-  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );

-

-procedure SDL_MonoSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;

-  DestSurface : PSDL_Surface; DestRect : PSDL_Rect; Color : cardinal );

-

-procedure SDL_TexturedSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;

-  DestSurface : PSDL_Surface; DestRect : PSDL_Rect; Texture : PSDL_Surface;

-  TextureRect : PSDL_Rect );

-

-procedure SDL_ZoomSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect; DstSurface : PSDL_Surface; DstRect : PSDL_Rect );

-

-procedure SDL_WarpSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect; DstSurface : PSDL_Surface; UL, UR, LR, LL : PPoint );

-

-// Flip procedures

-procedure SDL_FlipRectH( DstSurface : PSDL_Surface; Rect : PSDL_Rect );

-

-procedure SDL_FlipRectV( DstSurface : PSDL_Surface; Rect : PSDL_Rect );

-

-function PSDLRect( aLeft, aTop, aWidth, aHeight : integer ) : PSDL_Rect;

-

-function SDLRect( aLeft, aTop, aWidth, aHeight : integer ) : TSDL_Rect; overload;

-

-function SDLRect( aRect : TRect ) : TSDL_Rect; overload;

-

-function SDL_ScaleSurfaceRect( SrcSurface : PSDL_Surface; SrcX1, SrcY1, SrcW, SrcH,

-  Width, Height : integer ) : PSDL_Surface;

-

-procedure SDL_ScrollY( DstSurface : PSDL_Surface; DifY : integer );

-

-procedure SDL_ScrollX( DstSurface : PSDL_Surface; DifX : integer );

-

-procedure SDL_RotateDeg( DstSurface, SrcSurface : PSDL_Surface; SrcRect :

-  PSDL_Rect; DestX, DestY, OffsetX, OffsetY : Integer; Angle : Integer );

-

-procedure SDL_RotateRad( DstSurface, SrcSurface : PSDL_Surface; SrcRect :

-  PSDL_Rect; DestX, DestY, OffsetX, OffsetY : Integer; Angle : Single );

-

-function ValidateSurfaceRect( DstSurface : PSDL_Surface; dstrect : PSDL_Rect ) : TSDL_Rect;

-

-// Fill Rect routine

-procedure SDL_FillRectAdd( DstSurface : PSDL_Surface; dstrect : PSDL_Rect; color : UInt32 );

-

-procedure SDL_FillRectSub( DstSurface : PSDL_Surface; dstrect : PSDL_Rect; color : UInt32 );

-

-procedure SDL_GradientFillRect( DstSurface : PSDL_Surface; const Rect : PSDL_Rect; const StartColor, EndColor : TSDL_Color; const Style : TGradientStyle );

-

-// NOTE for All SDL_2xblit... function : the dest surface must be 2x of the source surface!

-procedure SDL_2xBlit( Src, Dest : PSDL_Surface );

-

-procedure SDL_Scanline2xBlit( Src, Dest : PSDL_Surface );

-

-procedure SDL_50Scanline2xBlit( Src, Dest : PSDL_Surface );

-

-//

-function SDL_PixelTestSurfaceVsRect( SrcSurface1 : PSDL_Surface; SrcRect1 :

-  PSDL_Rect; SrcRect2 : PSDL_Rect; Left1, Top1, Left2, Top2 : integer ) :

-  boolean;

-

-// Jason's boolean Surface functions

-procedure SDL_ORSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;

-  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );

-

-procedure SDL_ANDSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;

-  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );

-

-

-procedure SDL_GTSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;

-  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );

-

-procedure SDL_LTSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;

-  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );

-

-function SDL_ClipLine( var x1, y1, x2, y2 : Integer; ClipRect : PSDL_Rect ) : boolean;

-

-implementation

-

-uses

-  Math;

-

-function SDL_PixelTest( SrcSurface1 : PSDL_Surface; SrcRect1 : PSDL_Rect; SrcSurface2 :

-  PSDL_Surface; SrcRect2 : PSDL_Rect; Left1, Top1, Left2, Top2 : integer ) : boolean;

-var

-  Src_Rect1, Src_Rect2 : TSDL_Rect;

-  right1, bottom1 : integer;

-  right2, bottom2 : integer;

-  Scan1Start, Scan2Start, ScanWidth, ScanHeight : cardinal;

-  Mod1, Mod2   : cardinal;

-  Addr1, Addr2 : cardinal;

-  BPP          : cardinal;

-  Pitch1, Pitch2 : cardinal;

-  TransparentColor1, TransparentColor2 : cardinal;

-  tx, ty       : cardinal;

-  StartTick    : cardinal;

-  Color1, Color2 : cardinal;

-begin

-  Result := false;

-  if SrcRect1 = nil then

-  begin

-    with Src_Rect1 do

-    begin

-      x := 0;

-      y := 0;

-      w := SrcSurface1.w;

-      h := SrcSurface1.h;

-    end;

-  end

-  else

-    Src_Rect1 := SrcRect1^;

-  if SrcRect2 = nil then

-  begin

-    with Src_Rect2 do

-    begin

-      x := 0;

-      y := 0;

-      w := SrcSurface2.w;

-      h := SrcSurface2.h;

-    end;

-  end

-  else

-    Src_Rect2 := SrcRect2^;

-  with Src_Rect1 do

-  begin

-    Right1 := Left1 + w;

-    Bottom1 := Top1 + h;

-  end;

-  with Src_Rect2 do

-  begin

-    Right2 := Left2 + w;

-    Bottom2 := Top2 + h;

-  end;

-  if ( Left1 >= Right2 ) or ( Right1 <= Left2 ) or ( Top1 >= Bottom2 ) or ( Bottom1 <=

-    Top2 ) then

-    exit;

-  if Left1 <= Left2 then

-  begin

-    // 1. left, 2. right

-    Scan1Start := Src_Rect1.x + Left2 - Left1;

-    Scan2Start := Src_Rect2.x;

-    ScanWidth := Right1 - Left2;

-    with Src_Rect2 do

-      if ScanWidth > w then

-        ScanWidth := w;

-  end

-  else

-  begin

-    // 1. right, 2. left

-    Scan1Start := Src_Rect1.x;

-    Scan2Start := Src_Rect2.x + Left1 - Left2;

-    ScanWidth := Right2 - Left1;

-    with Src_Rect1 do

-      if ScanWidth > w then

-        ScanWidth := w;

-  end;

-  with SrcSurface1^ do

-  begin

-    Pitch1 := Pitch;

-    Addr1 := cardinal( Pixels );

-    inc( Addr1, Pitch1 * UInt32( Src_Rect1.y ) );

-    with format^ do

-    begin

-      BPP := BytesPerPixel;

-      TransparentColor1 := colorkey;

-    end;

-  end;

-  with SrcSurface2^ do

-  begin

-    TransparentColor2 := format.colorkey;

-    Pitch2 := Pitch;

-    Addr2 := cardinal( Pixels );

-    inc( Addr2, Pitch2 * UInt32( Src_Rect2.y ) );

-  end;

-  Mod1 := Pitch1 - ( ScanWidth * BPP );

-  Mod2 := Pitch2 - ( ScanWidth * BPP );

-  inc( Addr1, BPP * Scan1Start );

-  inc( Addr2, BPP * Scan2Start );

-  if Top1 <= Top2 then

-  begin

-    // 1. up, 2. down

-    ScanHeight := Bottom1 - Top2;

-    if ScanHeight > Src_Rect2.h then

-      ScanHeight := Src_Rect2.h;

-    inc( Addr1, Pitch1 * UInt32( Top2 - Top1 ) );

-  end

-  else

-  begin

-    // 1. down, 2. up

-    ScanHeight := Bottom2 - Top1;

-    if ScanHeight > Src_Rect1.h then

-      ScanHeight := Src_Rect1.h;

-    inc( Addr2, Pitch2 * UInt32( Top1 - Top2 ) );

-  end;

-  case BPP of

-    1 :

-      for ty := 1 to ScanHeight do

-      begin

-        for tx := 1 to ScanWidth do

-        begin

-          if ( PByte( Addr1 )^ <> TransparentColor1 ) and ( PByte( Addr2 )^ <>

-            TransparentColor2 ) then

-          begin

-            Result := true;

-            exit;

-          end;

-          inc( Addr1 );

-          inc( Addr2 );

-        end;

-        inc( Addr1, Mod1 );

-        inc( Addr2, Mod2 );

-      end;

-    2 :

-      for ty := 1 to ScanHeight do

-      begin

-        for tx := 1 to ScanWidth do

-        begin

-          if ( PWord( Addr1 )^ <> TransparentColor1 ) and ( PWord( Addr2 )^ <>

-            TransparentColor2 ) then

-          begin

-            Result := true;

-            exit;

-          end;

-          inc( Addr1, 2 );

-          inc( Addr2, 2 );

-        end;

-        inc( Addr1, Mod1 );

-        inc( Addr2, Mod2 );

-      end;

-    3 :

-      for ty := 1 to ScanHeight do

-      begin

-        for tx := 1 to ScanWidth do

-        begin

-          Color1 := PLongWord( Addr1 )^ and $00FFFFFF;

-          Color2 := PLongWord( Addr2 )^ and $00FFFFFF;

-          if ( Color1 <> TransparentColor1 ) and ( Color2 <> TransparentColor2 )

-            then

-          begin

-            Result := true;

-            exit;

-          end;

-          inc( Addr1, 3 );

-          inc( Addr2, 3 );

-        end;

-        inc( Addr1, Mod1 );

-        inc( Addr2, Mod2 );

-      end;

-    4 :

-      for ty := 1 to ScanHeight do

-      begin

-        for tx := 1 to ScanWidth do

-        begin

-          if ( PLongWord( Addr1 )^ <> TransparentColor1 ) and ( PLongWord( Addr2 )^ <>

-            TransparentColor2 ) then

-          begin

-            Result := true;

-            exit;

-          end;

-          inc( Addr1, 4 );

-          inc( Addr2, 4 );

-        end;

-        inc( Addr1, Mod1 );

-        inc( Addr2, Mod2 );

-      end;

-  end;

-end;

-

-procedure SDL_AddPixel( DstSurface : PSDL_Surface; x : cardinal; y : cardinal; Color :

-  cardinal );

-var

-  SrcColor     : cardinal;

-  Addr         : cardinal;

-  R, G, B      : cardinal;

-begin

-  if Color = 0 then

-    exit;

-  with DstSurface^ do

-  begin

-    Addr := cardinal( Pixels ) + y * Pitch + x * format.BytesPerPixel;

-    SrcColor := PUInt32( Addr )^;

-    case format.BitsPerPixel of

-      8 :

-        begin

-          R := SrcColor and $E0 + Color and $E0;

-          G := SrcColor and $1C + Color and $1C;

-          B := SrcColor and $03 + Color and $03;

-          if R > $E0 then

-            R := $E0;

-          if G > $1C then

-            G := $1C;

-          if B > $03 then

-            B := $03;

-          PUInt8( Addr )^ := R or G or B;

-        end;

-      15 :

-        begin

-          R := SrcColor and $7C00 + Color and $7C00;

-          G := SrcColor and $03E0 + Color and $03E0;

-          B := SrcColor and $001F + Color and $001F;

-          if R > $7C00 then

-            R := $7C00;

-          if G > $03E0 then

-            G := $03E0;

-          if B > $001F then

-            B := $001F;

-          PUInt16( Addr )^ := R or G or B;

-        end;

-      16 :

-        begin

-          R := SrcColor and $F800 + Color and $F800;

-          G := SrcColor and $07C0 + Color and $07C0;

-          B := SrcColor and $001F + Color and $001F;

-          if R > $F800 then

-            R := $F800;

-          if G > $07C0 then

-            G := $07C0;

-          if B > $001F then

-            B := $001F;

-          PUInt16( Addr )^ := R or G or B;

-        end;

-      24 :

-        begin

-          R := SrcColor and $00FF0000 + Color and $00FF0000;

-          G := SrcColor and $0000FF00 + Color and $0000FF00;

-          B := SrcColor and $000000FF + Color and $000000FF;

-          if R > $FF0000 then

-            R := $FF0000;

-          if G > $00FF00 then

-            G := $00FF00;

-          if B > $0000FF then

-            B := $0000FF;

-          PUInt32( Addr )^ := SrcColor and $FF000000 or R or G or B;

-        end;

-      32 :

-        begin

-          R := SrcColor and $00FF0000 + Color and $00FF0000;

-          G := SrcColor and $0000FF00 + Color and $0000FF00;

-          B := SrcColor and $000000FF + Color and $000000FF;

-          if R > $FF0000 then

-            R := $FF0000;

-          if G > $00FF00 then

-            G := $00FF00;

-          if B > $0000FF then

-            B := $0000FF;

-          PUInt32( Addr )^ := R or G or B;

-        end;

-    end;

-  end;

-end;

-

-procedure SDL_SubPixel( DstSurface : PSDL_Surface; x : cardinal; y : cardinal; Color :

-  cardinal );

-var

-  SrcColor     : cardinal;

-  Addr         : cardinal;

-  R, G, B      : cardinal;

-begin

-  if Color = 0 then

-    exit;

-  with DstSurface^ do

-  begin

-    Addr := cardinal( Pixels ) + y * Pitch + x * format.BytesPerPixel;

-    SrcColor := PUInt32( Addr )^;

-    case format.BitsPerPixel of

-      8 :

-        begin

-          R := SrcColor and $E0 - Color and $E0;

-          G := SrcColor and $1C - Color and $1C;

-          B := SrcColor and $03 - Color and $03;

-          if R > $E0 then

-            R := 0;

-          if G > $1C then

-            G := 0;

-          if B > $03 then

-            B := 0;

-          PUInt8( Addr )^ := R or G or B;

-        end;

-      15 :

-        begin

-          R := SrcColor and $7C00 - Color and $7C00;

-          G := SrcColor and $03E0 - Color and $03E0;

-          B := SrcColor and $001F - Color and $001F;

-          if R > $7C00 then

-            R := 0;

-          if G > $03E0 then

-            G := 0;

-          if B > $001F then

-            B := 0;

-          PUInt16( Addr )^ := R or G or B;

-        end;

-      16 :

-        begin

-          R := SrcColor and $F800 - Color and $F800;

-          G := SrcColor and $07C0 - Color and $07C0;

-          B := SrcColor and $001F - Color and $001F;

-          if R > $F800 then

-            R := 0;

-          if G > $07C0 then

-            G := 0;

-          if B > $001F then

-            B := 0;

-          PUInt16( Addr )^ := R or G or B;

-        end;

-      24 :

-        begin

-          R := SrcColor and $00FF0000 - Color and $00FF0000;

-          G := SrcColor and $0000FF00 - Color and $0000FF00;

-          B := SrcColor and $000000FF - Color and $000000FF;

-          if R > $FF0000 then

-            R := 0;

-          if G > $00FF00 then

-            G := 0;

-          if B > $0000FF then

-            B := 0;

-          PUInt32( Addr )^ := SrcColor and $FF000000 or R or G or B;

-        end;

-      32 :

-        begin

-          R := SrcColor and $00FF0000 - Color and $00FF0000;

-          G := SrcColor and $0000FF00 - Color and $0000FF00;

-          B := SrcColor and $000000FF - Color and $000000FF;

-          if R > $FF0000 then

-            R := 0;

-          if G > $00FF00 then

-            G := 0;

-          if B > $0000FF then

-            B := 0;

-          PUInt32( Addr )^ := R or G or B;

-        end;

-    end;

-  end;

-end;

-// This procedure works on 8, 15, 16, 24 and 32 bits color depth surfaces.

-// In 8 bit color depth mode the procedure works with the default packed

-//  palette (RRRGGGBB). It handles all clipping.

-

-procedure SDL_AddSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;

-  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );

-var

-  R, G, B, Pixel1, Pixel2, TransparentColor : cardinal;

-  Src, Dest    : TSDL_Rect;

-  Diff         : integer;

-  SrcAddr, DestAddr : cardinal;

-  WorkX, WorkY : word;

-  SrcMod, DestMod : cardinal;

-  Bits         : cardinal;

-begin

-  if ( SrcSurface = nil ) or ( DestSurface = nil ) then

-    exit; // Remove this to make it faster

-  if ( SrcSurface.Format.BitsPerPixel <> DestSurface.Format.BitsPerPixel ) then

-    exit; // Remove this to make it faster

-  if SrcRect = nil then

-  begin

-    with Src do

-    begin

-      x := 0;

-      y := 0;

-      w := SrcSurface.w;

-      h := SrcSurface.h;

-    end;

-  end

-  else

-    Src := SrcRect^;

-  if DestRect = nil then

-  begin

-    Dest.x := 0;

-    Dest.y := 0;

-  end

-  else

-    Dest := DestRect^;

-  Dest.w := Src.w;

-  Dest.h := Src.h;

-  with DestSurface.Clip_Rect do

-  begin

-    // Source's right side is greater than the dest.cliprect

-    if Dest.x + Src.w > x + w then

-    begin

-      smallint( Src.w ) := x + w - Dest.x;

-      smallint( Dest.w ) := x + w - Dest.x;

-      if smallint( Dest.w ) < 1 then

-        exit;

-    end;

-    // Source's bottom side is greater than the dest.clip

-    if Dest.y + Src.h > y + h then

-    begin

-      smallint( Src.h ) := y + h - Dest.y;

-      smallint( Dest.h ) := y + h - Dest.y;

-      if smallint( Dest.h ) < 1 then

-        exit;

-    end;

-    // Source's left side is less than the dest.clip

-    if Dest.x < x then

-    begin

-      Diff := x - Dest.x;

-      Src.x := Src.x + Diff;

-      smallint( Src.w ) := smallint( Src.w ) - Diff;

-      Dest.x := x;

-      smallint( Dest.w ) := smallint( Dest.w ) - Diff;

-      if smallint( Dest.w ) < 1 then

-        exit;

-    end;

-    // Source's Top side is less than the dest.clip

-    if Dest.y < y then

-    begin

-      Diff := y - Dest.y;

-      Src.y := Src.y + Diff;

-      smallint( Src.h ) := smallint( Src.h ) - Diff;

-      Dest.y := y;

-      smallint( Dest.h ) := smallint( Dest.h ) - Diff;

-      if smallint( Dest.h ) < 1 then

-        exit;

-    end;

-  end;

-  with SrcSurface^ do

-  begin

-    SrcAddr := cardinal( Pixels ) + UInt32( Src.y ) * Pitch + UInt32( Src.x ) *

-      Format.BytesPerPixel;

-    SrcMod := Pitch - Src.w * Format.BytesPerPixel;

-    TransparentColor := Format.colorkey;

-  end;

-  with DestSurface^ do

-  begin

-    DestAddr := cardinal( Pixels ) + UInt32( Dest.y ) * Pitch + UInt32( Dest.x ) *

-      Format.BytesPerPixel;

-    DestMod := Pitch - Dest.w * Format.BytesPerPixel;

-    Bits := Format.BitsPerPixel;

-  end;

-  SDL_LockSurface( SrcSurface );

-  SDL_LockSurface( DestSurface );

-  WorkY := Src.h;

-  case bits of

-    8 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt8( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt8( DestAddr )^;

-              if Pixel2 > 0 then

-              begin

-                R := Pixel1 and $E0 + Pixel2 and $E0;

-                G := Pixel1 and $1C + Pixel2 and $1C;

-                B := Pixel1 and $03 + Pixel2 and $03;

-                if R > $E0 then

-                  R := $E0;

-                if G > $1C then

-                  G := $1C;

-                if B > $03 then

-                  B := $03;

-                PUInt8( DestAddr )^ := R or G or B;

-              end

-              else

-                PUInt8( DestAddr )^ := Pixel1;

-            end;

-            inc( SrcAddr );

-            inc( DestAddr );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    15 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt16( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt16( DestAddr )^;

-              if Pixel2 > 0 then

-              begin

-                R := Pixel1 and $7C00 + Pixel2 and $7C00;

-                G := Pixel1 and $03E0 + Pixel2 and $03E0;

-                B := Pixel1 and $001F + Pixel2 and $001F;

-                if R > $7C00 then

-                  R := $7C00;

-                if G > $03E0 then

-                  G := $03E0;

-                if B > $001F then

-                  B := $001F;

-                PUInt16( DestAddr )^ := R or G or B;

-              end

-              else

-                PUInt16( DestAddr )^ := Pixel1;

-            end;

-            inc( SrcAddr, 2 );

-            inc( DestAddr, 2 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    16 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt16( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt16( DestAddr )^;

-              if Pixel2 > 0 then

-              begin

-                R := Pixel1 and $F800 + Pixel2 and $F800;

-                G := Pixel1 and $07E0 + Pixel2 and $07E0;

-                B := Pixel1 and $001F + Pixel2 and $001F;

-                if R > $F800 then

-                  R := $F800;

-                if G > $07E0 then

-                  G := $07E0;

-                if B > $001F then

-                  B := $001F;

-                PUInt16( DestAddr )^ := R or G or B;

-              end

-              else

-                PUInt16( DestAddr )^ := Pixel1;

-            end;

-            inc( SrcAddr, 2 );

-            inc( DestAddr, 2 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    24 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt32( SrcAddr )^ and $00FFFFFF;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt32( DestAddr )^ and $00FFFFFF;

-              if Pixel2 > 0 then

-              begin

-                R := Pixel1 and $FF0000 + Pixel2 and $FF0000;

-                G := Pixel1 and $00FF00 + Pixel2 and $00FF00;

-                B := Pixel1 and $0000FF + Pixel2 and $0000FF;

-                if R > $FF0000 then

-                  R := $FF0000;

-                if G > $00FF00 then

-                  G := $00FF00;

-                if B > $0000FF then

-                  B := $0000FF;

-                PUInt32( DestAddr )^ := PUInt32( DestAddr )^ and $FF000000 or ( R or G or B );

-              end

-              else

-                PUInt32( DestAddr )^ := PUInt32( DestAddr )^ and $FF000000 or Pixel1;

-            end;

-            inc( SrcAddr, 3 );

-            inc( DestAddr, 3 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    32 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt32( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt32( DestAddr )^;

-              if Pixel2 > 0 then

-              begin

-                R := Pixel1 and $FF0000 + Pixel2 and $FF0000;

-                G := Pixel1 and $00FF00 + Pixel2 and $00FF00;

-                B := Pixel1 and $0000FF + Pixel2 and $0000FF;

-                if R > $FF0000 then

-                  R := $FF0000;

-                if G > $00FF00 then

-                  G := $00FF00;

-                if B > $0000FF then

-                  B := $0000FF;

-                PUInt32( DestAddr )^ := R or G or B;

-              end

-              else

-                PUInt32( DestAddr )^ := Pixel1;

-            end;

-            inc( SrcAddr, 4 );

-            inc( DestAddr, 4 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-  end;

-  SDL_UnlockSurface( SrcSurface );

-  SDL_UnlockSurface( DestSurface );

-end;

-

-procedure SDL_SubSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;

-  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );

-var

-  R, G, B, Pixel1, Pixel2, TransparentColor : cardinal;

-  Src, Dest    : TSDL_Rect;

-  Diff         : integer;

-  SrcAddr, DestAddr : cardinal;

-  _ebx, _esi, _edi, _esp : cardinal;

-  WorkX, WorkY : word;

-  SrcMod, DestMod : cardinal;

-  Bits         : cardinal;

-begin

-  if ( SrcSurface = nil ) or ( DestSurface = nil ) then

-    exit; // Remove this to make it faster

-  if ( SrcSurface.Format.BitsPerPixel <> DestSurface.Format.BitsPerPixel ) then

-    exit; // Remove this to make it faster

-  if SrcRect = nil then

-  begin

-    with Src do

-    begin

-      x := 0;

-      y := 0;

-      w := SrcSurface.w;

-      h := SrcSurface.h;

-    end;

-  end

-  else

-    Src := SrcRect^;

-  if DestRect = nil then

-  begin

-    Dest.x := 0;

-    Dest.y := 0;

-  end

-  else

-    Dest := DestRect^;

-  Dest.w := Src.w;

-  Dest.h := Src.h;

-  with DestSurface.Clip_Rect do

-  begin

-    // Source's right side is greater than the dest.cliprect

-    if Dest.x + Src.w > x + w then

-    begin

-      smallint( Src.w ) := x + w - Dest.x;

-      smallint( Dest.w ) := x + w - Dest.x;

-      if smallint( Dest.w ) < 1 then

-        exit;

-    end;

-    // Source's bottom side is greater than the dest.clip

-    if Dest.y + Src.h > y + h then

-    begin

-      smallint( Src.h ) := y + h - Dest.y;

-      smallint( Dest.h ) := y + h - Dest.y;

-      if smallint( Dest.h ) < 1 then

-        exit;

-    end;

-    // Source's left side is less than the dest.clip

-    if Dest.x < x then

-    begin

-      Diff := x - Dest.x;

-      Src.x := Src.x + Diff;

-      smallint( Src.w ) := smallint( Src.w ) - Diff;

-      Dest.x := x;

-      smallint( Dest.w ) := smallint( Dest.w ) - Diff;

-      if smallint( Dest.w ) < 1 then

-        exit;

-    end;

-    // Source's Top side is less than the dest.clip

-    if Dest.y < y then

-    begin

-      Diff := y - Dest.y;

-      Src.y := Src.y + Diff;

-      smallint( Src.h ) := smallint( Src.h ) - Diff;

-      Dest.y := y;

-      smallint( Dest.h ) := smallint( Dest.h ) - Diff;

-      if smallint( Dest.h ) < 1 then

-        exit;

-    end;

-  end;

-  with SrcSurface^ do

-  begin

-    SrcAddr := cardinal( Pixels ) + UInt32( Src.y ) * Pitch + UInt32( Src.x ) *

-      Format.BytesPerPixel;

-    SrcMod := Pitch - Src.w * Format.BytesPerPixel;

-    TransparentColor := Format.colorkey;

-  end;

-  with DestSurface^ do

-  begin

-    DestAddr := cardinal( Pixels ) + UInt32( Dest.y ) * Pitch + UInt32( Dest.x ) *

-      Format.BytesPerPixel;

-    DestMod := Pitch - Dest.w * Format.BytesPerPixel;

-    Bits := DestSurface.Format.BitsPerPixel;

-  end;

-  SDL_LockSurface( SrcSurface );

-  SDL_LockSurface( DestSurface );

-  WorkY := Src.h;

-  case bits of

-    8 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt8( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt8( DestAddr )^;

-              if Pixel2 > 0 then

-              begin

-                R := Pixel2 and $E0 - Pixel1 and $E0;

-                G := Pixel2 and $1C - Pixel1 and $1C;

-                B := Pixel2 and $03 - Pixel1 and $03;

-                if R > $E0 then

-                  R := 0;

-                if G > $1C then

-                  G := 0;

-                if B > $03 then

-                  B := 0;

-                PUInt8( DestAddr )^ := R or G or B;

-              end;

-            end;

-            inc( SrcAddr );

-            inc( DestAddr );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    15 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt16( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt16( DestAddr )^;

-              if Pixel2 > 0 then

-              begin

-                R := Pixel2 and $7C00 - Pixel1 and $7C00;

-                G := Pixel2 and $03E0 - Pixel1 and $03E0;

-                B := Pixel2 and $001F - Pixel1 and $001F;

-                if R > $7C00 then

-                  R := 0;

-                if G > $03E0 then

-                  G := 0;

-                if B > $001F then

-                  B := 0;

-                PUInt16( DestAddr )^ := R or G or B;

-              end;

-            end;

-            inc( SrcAddr, 2 );

-            inc( DestAddr, 2 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    16 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt16( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt16( DestAddr )^;

-              if Pixel2 > 0 then

-              begin

-                R := Pixel2 and $F800 - Pixel1 and $F800;

-                G := Pixel2 and $07E0 - Pixel1 and $07E0;

-                B := Pixel2 and $001F - Pixel1 and $001F;

-                if R > $F800 then

-                  R := 0;

-                if G > $07E0 then

-                  G := 0;

-                if B > $001F then

-                  B := 0;

-                PUInt16( DestAddr )^ := R or G or B;

-              end;

-            end;

-            inc( SrcAddr, 2 );

-            inc( DestAddr, 2 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    24 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt32( SrcAddr )^ and $00FFFFFF;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt32( DestAddr )^ and $00FFFFFF;

-              if Pixel2 > 0 then

-              begin

-                R := Pixel2 and $FF0000 - Pixel1 and $FF0000;

-                G := Pixel2 and $00FF00 - Pixel1 and $00FF00;

-                B := Pixel2 and $0000FF - Pixel1 and $0000FF;

-                if R > $FF0000 then

-                  R := 0;

-                if G > $00FF00 then

-                  G := 0;

-                if B > $0000FF then

-                  B := 0;

-                PUInt32( DestAddr )^ := PUInt32( DestAddr )^ and $FF000000 or ( R or G or B );

-              end;

-            end;

-            inc( SrcAddr, 3 );

-            inc( DestAddr, 3 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    32 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt32( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt32( DestAddr )^;

-              if Pixel2 > 0 then

-              begin

-                R := Pixel2 and $FF0000 - Pixel1 and $FF0000;

-                G := Pixel2 and $00FF00 - Pixel1 and $00FF00;

-                B := Pixel2 and $0000FF - Pixel1 and $0000FF;

-                if R > $FF0000 then

-                  R := 0;

-                if G > $00FF00 then

-                  G := 0;

-                if B > $0000FF then

-                  B := 0;

-                PUInt32( DestAddr )^ := R or G or B;

-              end

-              else

-                PUInt32( DestAddr )^ := Pixel2;

-            end;

-            inc( SrcAddr, 4 );

-            inc( DestAddr, 4 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-  end;

-  SDL_UnlockSurface( SrcSurface );

-  SDL_UnlockSurface( DestSurface );

-end;

-

-procedure SDL_MonoSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;

-  DestSurface : PSDL_Surface; DestRect : PSDL_Rect; Color : cardinal );

-var

-  Src, Dest    : TSDL_Rect;

-  Diff         : integer;

-  SrcAddr, DestAddr : cardinal;

-  _ebx, _esi, _edi, _esp : cardinal;

-  WorkX, WorkY : word;

-  SrcMod, DestMod : cardinal;

-  TransparentColor, SrcColor : cardinal;

-  BPP          : cardinal;

-begin

-  if ( SrcSurface = nil ) or ( DestSurface = nil ) then

-    exit; // Remove this to make it faster

-  if ( SrcSurface.Format.BitsPerPixel <> DestSurface.Format.BitsPerPixel ) then

-    exit; // Remove this to make it faster

-  if SrcRect = nil then

-  begin

-    with Src do

-    begin

-      x := 0;

-      y := 0;

-      w := SrcSurface.w;

-      h := SrcSurface.h;

-    end;

-  end

-  else

-    Src := SrcRect^;

-  if DestRect = nil then

-  begin

-    Dest.x := 0;

-    Dest.y := 0;

-  end

-  else

-    Dest := DestRect^;

-  Dest.w := Src.w;

-  Dest.h := Src.h;

-  with DestSurface.Clip_Rect do

-  begin

-    // Source's right side is greater than the dest.cliprect

-    if Dest.x + Src.w > x + w then

-    begin

-      smallint( Src.w ) := x + w - Dest.x;

-      smallint( Dest.w ) := x + w - Dest.x;

-      if smallint( Dest.w ) < 1 then

-        exit;

-    end;

-    // Source's bottom side is greater than the dest.clip

-    if Dest.y + Src.h > y + h then

-    begin

-      smallint( Src.h ) := y + h - Dest.y;

-      smallint( Dest.h ) := y + h - Dest.y;

-      if smallint( Dest.h ) < 1 then

-        exit;

-    end;

-    // Source's left side is less than the dest.clip

-    if Dest.x < x then

-    begin

-      Diff := x - Dest.x;

-      Src.x := Src.x + Diff;

-      smallint( Src.w ) := smallint( Src.w ) - Diff;

-      Dest.x := x;

-      smallint( Dest.w ) := smallint( Dest.w ) - Diff;

-      if smallint( Dest.w ) < 1 then

-        exit;

-    end;

-    // Source's Top side is less than the dest.clip

-    if Dest.y < y then

-    begin

-      Diff := y - Dest.y;

-      Src.y := Src.y + Diff;

-      smallint( Src.h ) := smallint( Src.h ) - Diff;

-      Dest.y := y;

-      smallint( Dest.h ) := smallint( Dest.h ) - Diff;

-      if smallint( Dest.h ) < 1 then

-        exit;

-    end;

-  end;

-  with SrcSurface^ do

-  begin

-    SrcAddr := cardinal( Pixels ) + UInt32( Src.y ) * Pitch + UInt32( Src.x ) *

-      Format.BytesPerPixel;

-    SrcMod := Pitch - Src.w * Format.BytesPerPixel;

-    TransparentColor := Format.colorkey;

-  end;

-  with DestSurface^ do

-  begin

-    DestAddr := cardinal( Pixels ) + UInt32( Dest.y ) * Pitch + UInt32( Dest.x ) *

-      Format.BytesPerPixel;

-    DestMod := Pitch - Dest.w * Format.BytesPerPixel;

-    BPP := DestSurface.Format.BytesPerPixel;

-  end;

-  SDL_LockSurface( SrcSurface );

-  SDL_LockSurface( DestSurface );

-  WorkY := Src.h;

-  case BPP of

-    1 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            SrcColor := PUInt8( SrcAddr )^;

-            if SrcColor <> TransparentColor then

-              PUInt8( DestAddr )^ := SrcColor;

-            inc( SrcAddr );

-            inc( DestAddr );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    2 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            SrcColor := PUInt16( SrcAddr )^;

-            if SrcColor <> TransparentColor then

-              PUInt16( DestAddr )^ := SrcColor;

-            inc( SrcAddr );

-            inc( DestAddr );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    3 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            SrcColor := PUInt32( SrcAddr )^ and $FFFFFF;

-            if SrcColor <> TransparentColor then

-              PUInt32( DestAddr )^ := ( PUInt32( DestAddr )^ and $FFFFFF ) or SrcColor;

-            inc( SrcAddr );

-            inc( DestAddr );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    4 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            SrcColor := PUInt32( SrcAddr )^;

-            if SrcColor <> TransparentColor then

-              PUInt32( DestAddr )^ := SrcColor;

-            inc( SrcAddr );

-            inc( DestAddr );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-  end;

-  SDL_UnlockSurface( SrcSurface );

-  SDL_UnlockSurface( DestSurface );

-end;

-// TextureRect.w and TextureRect.h are not used.

-// The TextureSurface's size MUST larger than the drawing rectangle!!!

-

-procedure SDL_TexturedSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;

-  DestSurface : PSDL_Surface; DestRect : PSDL_Rect; Texture : PSDL_Surface;

-  TextureRect : PSDL_Rect );

-var

-  Src, Dest    : TSDL_Rect;

-  Diff         : integer;

-  SrcAddr, DestAddr, TextAddr : cardinal;

-  _ebx, _esi, _edi, _esp : cardinal;

-  WorkX, WorkY : word;

-  SrcMod, DestMod, TextMod : cardinal;

-  SrcColor, TransparentColor, TextureColor : cardinal;

-  BPP          : cardinal;

-begin

-  if ( SrcSurface = nil ) or ( DestSurface = nil ) then

-    exit; // Remove this to make it faster

-  if ( SrcSurface.Format.BitsPerPixel <> DestSurface.Format.BitsPerPixel ) then

-    exit; // Remove this to make it faster

-  if SrcRect = nil then

-  begin

-    with Src do

-    begin

-      x := 0;

-      y := 0;

-      w := SrcSurface.w;

-      h := SrcSurface.h;

-    end;

-  end

-  else

-    Src := SrcRect^;

-  if DestRect = nil then

-  begin

-    Dest.x := 0;

-    Dest.y := 0;

-  end

-  else

-    Dest := DestRect^;

-  Dest.w := Src.w;

-  Dest.h := Src.h;

-  with DestSurface.Clip_Rect do

-  begin

-    // Source's right side is greater than the dest.cliprect

-    if Dest.x + Src.w > x + w then

-    begin

-      smallint( Src.w ) := x + w - Dest.x;

-      smallint( Dest.w ) := x + w - Dest.x;

-      if smallint( Dest.w ) < 1 then

-        exit;

-    end;

-    // Source's bottom side is greater than the dest.clip

-    if Dest.y + Src.h > y + h then

-    begin

-      smallint( Src.h ) := y + h - Dest.y;

-      smallint( Dest.h ) := y + h - Dest.y;

-      if smallint( Dest.h ) < 1 then

-        exit;

-    end;

-    // Source's left side is less than the dest.clip

-    if Dest.x < x then

-    begin

-      Diff := x - Dest.x;

-      Src.x := Src.x + Diff;

-      smallint( Src.w ) := smallint( Src.w ) - Diff;

-      Dest.x := x;

-      smallint( Dest.w ) := smallint( Dest.w ) - Diff;

-      if smallint( Dest.w ) < 1 then

-        exit;

-    end;

-    // Source's Top side is less than the dest.clip

-    if Dest.y < y then

-    begin

-      Diff := y - Dest.y;

-      Src.y := Src.y + Diff;

-      smallint( Src.h ) := smallint( Src.h ) - Diff;

-      Dest.y := y;

-      smallint( Dest.h ) := smallint( Dest.h ) - Diff;

-      if smallint( Dest.h ) < 1 then

-        exit;

-    end;

-  end;

-  with SrcSurface^ do

-  begin

-    SrcAddr := cardinal( Pixels ) + UInt32( Src.y ) * Pitch + UInt32( Src.x ) *

-      Format.BytesPerPixel;

-    SrcMod := Pitch - Src.w * Format.BytesPerPixel;

-    TransparentColor := format.colorkey;

-  end;

-  with DestSurface^ do

-  begin

-    DestAddr := cardinal( Pixels ) + UInt32( Dest.y ) * Pitch + UInt32( Dest.x ) *

-      Format.BytesPerPixel;

-    DestMod := Pitch - Dest.w * Format.BytesPerPixel;

-    BPP := DestSurface.Format.BitsPerPixel;

-  end;

-  with Texture^ do

-  begin

-    TextAddr := cardinal( Pixels ) + UInt32( TextureRect.y ) * Pitch +

-      UInt32( TextureRect.x ) * Format.BytesPerPixel;

-    TextMod := Pitch - Src.w * Format.BytesPerPixel;

-  end;

-  SDL_LockSurface( SrcSurface );

-  SDL_LockSurface( DestSurface );

-  SDL_LockSurface( Texture );

-  WorkY := Src.h;

-  case BPP of

-    1 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            SrcColor := PUInt8( SrcAddr )^;

-            if SrcColor <> TransparentColor then

-              PUInt8( DestAddr )^ := PUint8( TextAddr )^;

-            inc( SrcAddr );

-            inc( DestAddr );

-            inc( TextAddr );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          inc( TextAddr, TextMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    2 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            SrcColor := PUInt16( SrcAddr )^;

-            if SrcColor <> TransparentColor then

-              PUInt16( DestAddr )^ := PUInt16( TextAddr )^;

-            inc( SrcAddr );

-            inc( DestAddr );

-            inc( TextAddr );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          inc( TextAddr, TextMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    3 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            SrcColor := PUInt32( SrcAddr )^ and $FFFFFF;

-            if SrcColor <> TransparentColor then

-              PUInt32( DestAddr )^ := ( PUInt32( DestAddr )^ and $FFFFFF ) or ( PUInt32( TextAddr )^ and $FFFFFF );

-            inc( SrcAddr );

-            inc( DestAddr );

-            inc( TextAddr );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          inc( TextAddr, TextMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    4 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            SrcColor := PUInt32( SrcAddr )^;

-            if SrcColor <> TransparentColor then

-              PUInt32( DestAddr )^ := PUInt32( TextAddr )^;

-            inc( SrcAddr );

-            inc( DestAddr );

-            inc( TextAddr );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          inc( TextAddr, TextMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-  end;

-  SDL_UnlockSurface( SrcSurface );

-  SDL_UnlockSurface( DestSurface );

-  SDL_UnlockSurface( Texture );

-end;

-

-procedure SDL_ZoomSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect; DstSurface : PSDL_Surface; DstRect : PSDL_Rect );

-var

-  xc, yc       : cardinal;

-  rx, wx, ry, wy, ry16 : cardinal;

-  color        : cardinal;

-  modx, mody   : cardinal;

-begin

-  // Warning! No checks for surface pointers!!!

-  if srcrect = nil then

-    srcrect := @SrcSurface.clip_rect;

-  if dstrect = nil then

-    dstrect := @DstSurface.clip_rect;

-  if SDL_MustLock( SrcSurface ) then

-    SDL_LockSurface( SrcSurface );

-  if SDL_MustLock( DstSurface ) then

-    SDL_LockSurface( DstSurface );

-  modx := trunc( ( srcrect.w / dstrect.w ) * 65536 );

-  mody := trunc( ( srcrect.h / dstrect.h ) * 65536 );

-  //rx := srcrect.x * 65536;

-  ry := srcrect.y * 65536;

-  wy := dstrect.y;

-  for yc := 0 to dstrect.h - 1 do

-  begin

-    rx := srcrect.x * 65536;

-    wx := dstrect.x;

-    ry16 := ry shr 16;

-    for xc := 0 to dstrect.w - 1 do

-    begin

-      color := SDL_GetPixel( SrcSurface, rx shr 16, ry16 );

-      SDL_PutPixel( DstSurface, wx, wy, color );

-      rx := rx + modx;

-      inc( wx );

-    end;

-    ry := ry + mody;

-    inc( wy );

-  end;

-  if SDL_MustLock( SrcSurface ) then

-    SDL_UnlockSurface( SrcSurface );

-  if SDL_MustLock( DstSurface ) then

-    SDL_UnlockSurface( DstSurface );

-end;

-// Re-map a rectangular area into an area defined by four vertices

-// Converted from C to Pascal by KiCHY

-

-procedure SDL_WarpSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect; DstSurface : PSDL_Surface; UL, UR, LR, LL : PPoint );

-const

-  SHIFTS       = 15; // Extend ints to limit round-off error (try 2 - 20)

-  THRESH       = 1 shl SHIFTS; // Threshold for pixel size value

-  procedure CopySourceToDest( UL, UR, LR, LL : TPoint; x1, y1, x2, y2 : cardinal );

-  var

-    tm, lm, rm, bm, m : TPoint;

-    mx, my     : cardinal;

-    cr         : cardinal;

-  begin

-    // Does the destination area specify a single pixel?

-    if ( ( abs( ul.x - ur.x ) < THRESH ) and

-      ( abs( ul.x - lr.x ) < THRESH ) and

-      ( abs( ul.x - ll.x ) < THRESH ) and

-      ( abs( ul.y - ur.y ) < THRESH ) and

-      ( abs( ul.y - lr.y ) < THRESH ) and

-      ( abs( ul.y - ll.y ) < THRESH ) ) then

-    begin // Yes

-      cr := SDL_GetPixel( SrcSurface, ( x1 shr SHIFTS ), ( y1 shr SHIFTS ) );

-      SDL_PutPixel( DstSurface, ( ul.x shr SHIFTS ), ( ul.y shr SHIFTS ), cr );

-    end

-    else

-    begin // No

-      // Quarter the source and the destination, and then recurse

-      tm.x := ( ul.x + ur.x ) shr 1;

-      tm.y := ( ul.y + ur.y ) shr 1;

-      bm.x := ( ll.x + lr.x ) shr 1;

-      bm.y := ( ll.y + lr.y ) shr 1;

-      lm.x := ( ul.x + ll.x ) shr 1;

-      lm.y := ( ul.y + ll.y ) shr 1;

-      rm.x := ( ur.x + lr.x ) shr 1;

-      rm.y := ( ur.y + lr.y ) shr 1;

-      m.x := ( tm.x + bm.x ) shr 1;

-      m.y := ( tm.y + bm.y ) shr 1;

-      mx := ( x1 + x2 ) shr 1;

-      my := ( y1 + y2 ) shr 1;

-      CopySourceToDest( ul, tm, m, lm, x1, y1, mx, my );

-      CopySourceToDest( tm, ur, rm, m, mx, y1, x2, my );

-      CopySourceToDest( m, rm, lr, bm, mx, my, x2, y2 );

-      CopySourceToDest( lm, m, bm, ll, x1, my, mx, y2 );

-    end;

-  end;

-var

-  _UL, _UR, _LR, _LL : TPoint;

-  Rect_x, Rect_y, Rect_w, Rect_h : integer;

-begin

-  if SDL_MustLock( SrcSurface ) then

-    SDL_LockSurface( SrcSurface );

-  if SDL_MustLock( DstSurface ) then

-    SDL_LockSurface( DstSurface );

-  if SrcRect = nil then

-  begin

-    Rect_x := 0;

-    Rect_y := 0;

-    Rect_w := ( SrcSurface.w - 1 ) shl SHIFTS;

-    Rect_h := ( SrcSurface.h - 1 ) shl SHIFTS;

-  end

-  else

-  begin

-    Rect_x := SrcRect.x;

-    Rect_y := SrcRect.y;

-    Rect_w := ( SrcRect.w - 1 ) shl SHIFTS;

-    Rect_h := ( SrcRect.h - 1 ) shl SHIFTS;

-  end;

-  // Shift all values to help reduce round-off error.

-  _ul.x := ul.x shl SHIFTS;

-  _ul.y := ul.y shl SHIFTS;

-  _ur.x := ur.x shl SHIFTS;

-  _ur.y := ur.y shl SHIFTS;

-  _lr.x := lr.x shl SHIFTS;

-  _lr.y := lr.y shl SHIFTS;

-  _ll.x := ll.x shl SHIFTS;

-  _ll.y := ll.y shl SHIFTS;

-  CopySourceToDest( _ul, _ur, _lr, _ll, Rect_x, Rect_y, Rect_w, Rect_h );

-  if SDL_MustLock( SrcSurface ) then

-    SDL_UnlockSurface( SrcSurface );

-  if SDL_MustLock( DstSurface ) then

-    SDL_UnlockSurface( DstSurface );

-end;

-

-// Draw a line between x1,y1 and x2,y2 to the given surface

-// NOTE: The surface must be locked before calling this!

-

-procedure SDL_DrawLine( DstSurface : PSDL_Surface; x1, y1, x2, y2 : integer; Color :

-  cardinal );

-var

-  dx, dy, sdx, sdy, x, y, px, py : integer;

-begin

-  dx := x2 - x1;

-  dy := y2 - y1;

-  if dx < 0 then

-    sdx := -1

-  else

-    sdx := 1;

-  if dy < 0 then

-    sdy := -1

-  else

-    sdy := 1;

-  dx := sdx * dx + 1;

-  dy := sdy * dy + 1;

-  x := 0;

-  y := 0;

-  px := x1;

-  py := y1;

-  if dx >= dy then

-  begin

-    for x := 0 to dx - 1 do

-    begin

-      SDL_PutPixel( DstSurface, px, py, Color );

-      y := y + dy;

-      if y >= dx then

-      begin

-        y := y - dx;

-        py := py + sdy;

-      end;

-      px := px + sdx;

-    end;

-  end

-  else

-  begin

-    for y := 0 to dy - 1 do

-    begin

-      SDL_PutPixel( DstSurface, px, py, Color );

-      x := x + dx;

-      if x >= dy then

-      begin

-        x := x - dy;

-        px := px + sdx;

-      end;

-      py := py + sdy;

-    end;

-  end;

-end;

-

-// Draw a dashed line between x1,y1 and x2,y2 to the given surface

-// NOTE: The surface must be locked before calling this!

-

-procedure SDL_DrawLine( DstSurface : PSDL_Surface; x1, y1, x2, y2 : integer; Color :

-  cardinal; DashLength, DashSpace : byte ); overload;

-var

-  dx, dy, sdx, sdy, x, y, px, py, counter : integer; drawdash : boolean;

-begin

-  counter := 0;

-  drawdash := true; //begin line drawing with dash

-

-  //Avoid invalid user-passed dash parameters

-  if ( DashLength < 1 )

-    then

-    DashLength := 1;

-  if ( DashSpace < 1 )

-    then

-    DashSpace := 0;

-

-  dx := x2 - x1;

-  dy := y2 - y1;

-  if dx < 0 then

-    sdx := -1

-  else

-    sdx := 1;

-  if dy < 0 then

-    sdy := -1

-  else

-    sdy := 1;

-  dx := sdx * dx + 1;

-  dy := sdy * dy + 1;

-  x := 0;

-  y := 0;

-  px := x1;

-  py := y1;

-  if dx >= dy then

-  begin

-    for x := 0 to dx - 1 do

-    begin

-

-      //Alternate drawing dashes, or leaving spaces

-      if drawdash then

-      begin

-        SDL_PutPixel( DstSurface, px, py, Color );

-        inc( counter );

-        if ( counter > DashLength - 1 ) and ( DashSpace > 0 ) then

-        begin

-          drawdash := false;

-          counter := 0;

-        end;

-      end

-      else //space

-      begin

-        inc( counter );

-        if counter > DashSpace - 1 then

-        begin

-          drawdash := true;

-          counter := 0;

-        end;

-      end;

-

-      y := y + dy;

-      if y >= dx then

-      begin

-        y := y - dx;

-        py := py + sdy;

-      end;

-      px := px + sdx;

-    end;

-  end

-  else

-  begin

-    for y := 0 to dy - 1 do

-    begin

-

-      //Alternate drawing dashes, or leaving spaces

-      if drawdash then

-      begin

-        SDL_PutPixel( DstSurface, px, py, Color );

-        inc( counter );

-        if ( counter > DashLength - 1 ) and ( DashSpace > 0 ) then

-        begin

-          drawdash := false;

-          counter := 0;

-        end;

-      end

-      else //space

-      begin

-        inc( counter );

-        if counter > DashSpace - 1 then

-        begin

-          drawdash := true;

-          counter := 0;

-        end;

-      end;

-

-      x := x + dx;

-      if x >= dy then

-      begin

-        x := x - dy;

-        px := px + sdx;

-      end;

-      py := py + sdy;

-    end;

-  end;

-end;

-

-procedure SDL_AddLine( DstSurface : PSDL_Surface; x1, y1, x2, y2 : integer; Color :

-  cardinal );

-var

-  dx, dy, sdx, sdy, x, y, px, py : integer;

-begin

-  dx := x2 - x1;

-  dy := y2 - y1;

-  if dx < 0 then

-    sdx := -1

-  else

-    sdx := 1;

-  if dy < 0 then

-    sdy := -1

-  else

-    sdy := 1;

-  dx := sdx * dx + 1;

-  dy := sdy * dy + 1;

-  x := 0;

-  y := 0;

-  px := x1;

-  py := y1;

-  if dx >= dy then

-  begin

-    for x := 0 to dx - 1 do

-    begin

-      SDL_AddPixel( DstSurface, px, py, Color );

-      y := y + dy;

-      if y >= dx then

-      begin

-        y := y - dx;

-        py := py + sdy;

-      end;

-      px := px + sdx;

-    end;

-  end

-  else

-  begin

-    for y := 0 to dy - 1 do

-    begin

-      SDL_AddPixel( DstSurface, px, py, Color );

-      x := x + dx;

-      if x >= dy then

-      begin

-        x := x - dy;

-        px := px + sdx;

-      end;

-      py := py + sdy;

-    end;

-  end;

-end;

-

-procedure SDL_SubLine( DstSurface : PSDL_Surface; x1, y1, x2, y2 : integer; Color :

-  cardinal );

-var

-  dx, dy, sdx, sdy, x, y, px, py : integer;

-begin

-  dx := x2 - x1;

-  dy := y2 - y1;

-  if dx < 0 then

-    sdx := -1

-  else

-    sdx := 1;

-  if dy < 0 then

-    sdy := -1

-  else

-    sdy := 1;

-  dx := sdx * dx + 1;

-  dy := sdy * dy + 1;

-  x := 0;

-  y := 0;

-  px := x1;

-  py := y1;

-  if dx >= dy then

-  begin

-    for x := 0 to dx - 1 do

-    begin

-      SDL_SubPixel( DstSurface, px, py, Color );

-      y := y + dy;

-      if y >= dx then

-      begin

-        y := y - dx;

-        py := py + sdy;

-      end;

-      px := px + sdx;

-    end;

-  end

-  else

-  begin

-    for y := 0 to dy - 1 do

-    begin

-      SDL_SubPixel( DstSurface, px, py, Color );

-      x := x + dx;

-      if x >= dy then

-      begin

-        x := x - dy;

-        px := px + sdx;

-      end;

-      py := py + sdy;

-    end;

-  end;

-end;

-

-// flips a rectangle vertically on given surface

-

-procedure SDL_FlipRectV( DstSurface : PSDL_Surface; Rect : PSDL_Rect );

-var

-  TmpRect      : TSDL_Rect;

-  Locked       : boolean;

-  y, FlipLength, RowLength : integer;

-  Row1, Row2   : Pointer;

-  OneRow       : TByteArray; // Optimize it if you wish

-begin

-  if DstSurface <> nil then

-  begin

-    if Rect = nil then

-    begin // if Rect=nil then we flip the whole surface

-      TmpRect := SDLRect( 0, 0, DstSurface.w, DstSurface.h );

-      Rect := @TmpRect;

-    end;

-    FlipLength := Rect^.h shr 1 - 1;

-    RowLength := Rect^.w * DstSurface^.format.BytesPerPixel;

-    if SDL_MustLock( DstSurface ) then

-    begin

-      Locked := true;

-      SDL_LockSurface( DstSurface );

-    end

-    else

-      Locked := false;

-    Row1 := pointer( cardinal( DstSurface^.Pixels ) + UInt32( Rect^.y ) *

-      DstSurface^.Pitch );

-    Row2 := pointer( cardinal( DstSurface^.Pixels ) + ( UInt32( Rect^.y ) + Rect^.h - 1 )

-      * DstSurface^.Pitch );

-    for y := 0 to FlipLength do

-    begin

-      Move( Row1^, OneRow, RowLength );

-      Move( Row2^, Row1^, RowLength );

-      Move( OneRow, Row2^, RowLength );

-      inc( cardinal( Row1 ), DstSurface^.Pitch );

-      dec( cardinal( Row2 ), DstSurface^.Pitch );

-    end;

-    if Locked then

-      SDL_UnlockSurface( DstSurface );

-  end;

-end;

-

-// flips a rectangle horizontally on given surface

-

-procedure SDL_FlipRectH( DstSurface : PSDL_Surface; Rect : PSDL_Rect );

-type

-  T24bit = packed array[ 0..2 ] of byte;

-  T24bitArray = packed array[ 0..8191 ] of T24bit;

-  P24bitArray = ^T24bitArray;

-  TLongWordArray = array[ 0..8191 ] of LongWord;

-  PLongWordArray = ^TLongWordArray;

-var

-  TmpRect      : TSDL_Rect;

-  Row8bit      : PByteArray;

-  Row16bit     : PWordArray;

-  Row24bit     : P24bitArray;

-  Row32bit     : PLongWordArray;

-  y, x, RightSide, FlipLength : integer;

-  Pixel        : cardinal;

-  Pixel24      : T24bit;

-  Locked       : boolean;

-begin

-  if DstSurface <> nil then

-  begin

-    if Rect = nil then

-    begin

-      TmpRect := SDLRect( 0, 0, DstSurface.w, DstSurface.h );

-      Rect := @TmpRect;

-    end;

-    FlipLength := Rect^.w shr 1 - 1;

-    if SDL_MustLock( DstSurface ) then

-    begin

-      Locked := true;

-      SDL_LockSurface( DstSurface );

-    end

-    else

-      Locked := false;

-    case DstSurface^.format.BytesPerPixel of

-      1 :

-        begin

-          Row8Bit := pointer( cardinal( DstSurface^.pixels ) + UInt32( Rect^.y ) *

-            DstSurface^.pitch );

-          for y := 1 to Rect^.h do

-          begin

-            RightSide := Rect^.w - 1;

-            for x := 0 to FlipLength do

-            begin

-              Pixel := Row8Bit^[ x ];

-              Row8Bit^[ x ] := Row8Bit^[ RightSide ];

-              Row8Bit^[ RightSide ] := Pixel;

-              dec( RightSide );

-            end;

-            inc( cardinal( Row8Bit ), DstSurface^.pitch );

-          end;

-        end;

-      2 :

-        begin

-          Row16Bit := pointer( cardinal( DstSurface^.pixels ) + UInt32( Rect^.y ) *

-            DstSurface^.pitch );

-          for y := 1 to Rect^.h do

-          begin

-            RightSide := Rect^.w - 1;

-            for x := 0 to FlipLength do

-            begin

-              Pixel := Row16Bit^[ x ];

-              Row16Bit^[ x ] := Row16Bit^[ RightSide ];

-              Row16Bit^[ RightSide ] := Pixel;

-              dec( RightSide );

-            end;

-            inc( cardinal( Row16Bit ), DstSurface^.pitch );

-          end;

-        end;

-      3 :

-        begin

-          Row24Bit := pointer( cardinal( DstSurface^.pixels ) + UInt32( Rect^.y ) *

-            DstSurface^.pitch );

-          for y := 1 to Rect^.h do

-          begin

-            RightSide := Rect^.w - 1;

-            for x := 0 to FlipLength do

-            begin

-              Pixel24 := Row24Bit^[ x ];

-              Row24Bit^[ x ] := Row24Bit^[ RightSide ];

-              Row24Bit^[ RightSide ] := Pixel24;

-              dec( RightSide );

-            end;

-            inc( cardinal( Row24Bit ), DstSurface^.pitch );

-          end;

-        end;

-      4 :

-        begin

-          Row32Bit := pointer( cardinal( DstSurface^.pixels ) + UInt32( Rect^.y ) *

-            DstSurface^.pitch );

-          for y := 1 to Rect^.h do

-          begin

-            RightSide := Rect^.w - 1;

-            for x := 0 to FlipLength do

-            begin

-              Pixel := Row32Bit^[ x ];

-              Row32Bit^[ x ] := Row32Bit^[ RightSide ];

-              Row32Bit^[ RightSide ] := Pixel;

-              dec( RightSide );

-            end;

-            inc( cardinal( Row32Bit ), DstSurface^.pitch );

-          end;

-        end;

-    end;

-    if Locked then

-      SDL_UnlockSurface( DstSurface );

-  end;

-end;

-

-// Use with caution! The procedure allocates memory for TSDL_Rect and return with its pointer.

-// But you MUST free it after you don't need it anymore!!!

-

-function PSDLRect( aLeft, aTop, aWidth, aHeight : integer ) : PSDL_Rect;

-var

-  Rect         : PSDL_Rect;

-begin

-  New( Rect );

-  with Rect^ do

-  begin

-    x := aLeft;

-    y := aTop;

-    w := aWidth;

-    h := aHeight;

-  end;

-  Result := Rect;

-end;

-

-function SDLRect( aLeft, aTop, aWidth, aHeight : integer ) : TSDL_Rect;

-begin

-  with result do

-  begin

-    x := aLeft;

-    y := aTop;

-    w := aWidth;

-    h := aHeight;

-  end;

-end;

-

-function SDLRect( aRect : TRect ) : TSDL_Rect;

-begin

-  with aRect do

-    result := SDLRect( Left, Top, Right - Left, Bottom - Top );

-end;

-

-procedure SDL_Stretch8( Surface, Dst_Surface : PSDL_Surface; x1, x2, y1, y2, yr, yw,

-  depth : integer );

-var

-  dx, dy, e, d, dx2 : integer;

-  src_pitch, dst_pitch : uint16;

-  src_pixels, dst_pixels : PUint8;

-begin

-  if ( yw >= dst_surface^.h ) then

-    exit;

-  dx := ( x2 - x1 );

-  dy := ( y2 - y1 );

-  dy := dy shl 1;

-  e := dy - dx;

-  dx2 := dx shl 1;

-  src_pitch := Surface^.pitch;

-  dst_pitch := dst_surface^.pitch;

-  src_pixels := PUint8( integer( Surface^.pixels ) + yr * src_pitch + y1 * depth );

-  dst_pixels := PUint8( integer( dst_surface^.pixels ) + yw * dst_pitch + x1 *

-    depth );

-  for d := 0 to dx - 1 do

-  begin

-    move( src_pixels^, dst_pixels^, depth );

-    while ( e >= 0 ) do

-    begin

-      inc( src_pixels, depth );

-      e := e - dx2;

-    end;

-    inc( dst_pixels, depth );

-    e := e + dy;

-  end;

-end;

-

-function sign( x : integer ) : integer;

-begin

-  if x > 0 then

-    result := 1

-  else

-    result := -1;

-end;

-

-// Stretches a part of a surface

-

-function SDL_ScaleSurfaceRect( SrcSurface : PSDL_Surface; SrcX1, SrcY1, SrcW, SrcH,

-  Width, Height : integer ) : PSDL_Surface;

-var

-  dst_surface  : PSDL_Surface;

-  dx, dy, e, d, dx2, srcx2, srcy2 : integer;

-  destx1, desty1 : integer;

-begin

-  srcx2 := srcx1 + SrcW;

-  srcy2 := srcy1 + SrcH;

-  result := nil;

-  destx1 := 0;

-  desty1 := 0;

-  dx := abs( integer( Height - desty1 ) );

-  dy := abs( integer( SrcY2 - SrcY1 ) );

-  e := ( dy shl 1 ) - dx;

-  dx2 := dx shl 1;

-  dy := dy shl 1;

-  dst_surface := SDL_CreateRGBSurface( SDL_HWPALETTE, width - destx1, Height -

-    desty1,

-    SrcSurface^.Format^.BitsPerPixel,

-    SrcSurface^.Format^.RMask,

-    SrcSurface^.Format^.GMask,

-    SrcSurface^.Format^.BMask,

-    SrcSurface^.Format^.AMask );

-  if ( dst_surface^.format^.BytesPerPixel = 1 ) then

-    SDL_SetColors( dst_surface, @SrcSurface^.format^.palette^.colors^[ 0 ], 0, 256 );

-  SDL_SetColorKey( dst_surface, sdl_srccolorkey, SrcSurface^.format^.colorkey );

-  if ( SDL_MustLock( dst_surface ) ) then

-    if ( SDL_LockSurface( dst_surface ) < 0 ) then

-      exit;

-  for d := 0 to dx - 1 do

-  begin

-    SDL_Stretch8( SrcSurface, dst_surface, destx1, Width, SrcX1, SrcX2, SrcY1, desty1,

-      SrcSurface^.format^.BytesPerPixel );

-    while e >= 0 do

-    begin

-      inc( SrcY1 );

-      e := e - dx2;

-    end;

-    inc( desty1 );

-    e := e + dy;

-  end;

-  if SDL_MUSTLOCK( dst_surface ) then

-    SDL_UnlockSurface( dst_surface );

-  result := dst_surface;

-end;

-

-procedure SDL_MoveLine( Surface : PSDL_Surface; x1, x2, y1, xofs, depth : integer );

-var

-  src_pixels, dst_pixels : PUint8;

-  i            : integer;

-begin

-  src_pixels := PUint8( integer( Surface^.pixels ) + Surface^.w * y1 * depth + x2 *

-    depth );

-  dst_pixels := PUint8( integer( Surface^.pixels ) + Surface^.w * y1 * depth + ( x2

-    + xofs ) * depth );

-  for i := x2 downto x1 do

-  begin

-    move( src_pixels^, dst_pixels^, depth );

-    dec( src_pixels );

-    dec( dst_pixels );

-  end;

-end;

-{ Return the pixel value at (x, y)

-NOTE: The surface must be locked before calling this! }

-

-function SDL_GetPixel( SrcSurface : PSDL_Surface; x : integer; y : integer ) : Uint32;

-var

-  bpp          : UInt32;

-  p            : PInteger;

-begin

-  bpp := SrcSurface.format.BytesPerPixel;

-  // Here p is the address to the pixel we want to retrieve

-  p := Pointer( Uint32( SrcSurface.pixels ) + UInt32( y ) * SrcSurface.pitch + UInt32( x ) *

-    bpp );

-  case bpp of

-    1 : result := PUint8( p )^;

-    2 : result := PUint16( p )^;

-    3 :

-      if ( SDL_BYTEORDER = SDL_BIG_ENDIAN ) then

-        result := PUInt8Array( p )[ 0 ] shl 16 or PUInt8Array( p )[ 1 ] shl 8 or

-          PUInt8Array( p )[ 2 ]

-      else

-        result := PUInt8Array( p )[ 0 ] or PUInt8Array( p )[ 1 ] shl 8 or

-          PUInt8Array( p )[ 2 ] shl 16;

-    4 : result := PUint32( p )^;

-  else

-    result := 0; // shouldn't happen, but avoids warnings

-  end;

-end;

-{ Set the pixel at (x, y) to the given value

-  NOTE: The surface must be locked before calling this! }

-

-procedure SDL_PutPixel( DstSurface : PSDL_Surface; x : integer; y : integer; pixel :

-  Uint32 );

-var

-  bpp          : UInt32;

-  p            : PInteger;

-begin

-  bpp := DstSurface.format.BytesPerPixel;

-  p := Pointer( Uint32( DstSurface.pixels ) + UInt32( y ) * DstSurface.pitch + UInt32( x )

-    * bpp );

-  case bpp of

-    1 : PUint8( p )^ := pixel;

-    2 : PUint16( p )^ := pixel;

-    3 :

-      if ( SDL_BYTEORDER = SDL_BIG_ENDIAN ) then

-      begin

-        PUInt8Array( p )[ 0 ] := ( pixel shr 16 ) and $FF;

-        PUInt8Array( p )[ 1 ] := ( pixel shr 8 ) and $FF;

-        PUInt8Array( p )[ 2 ] := pixel and $FF;

-      end

-      else

-      begin

-        PUInt8Array( p )[ 0 ] := pixel and $FF;

-        PUInt8Array( p )[ 1 ] := ( pixel shr 8 ) and $FF;

-        PUInt8Array( p )[ 2 ] := ( pixel shr 16 ) and $FF;

-      end;

-    4 :

-      PUint32( p )^ := pixel;

-  end;

-end;

-

-procedure SDL_ScrollY( DstSurface : PSDL_Surface; DifY : integer );

-var

-  r1, r2       : TSDL_Rect;

-  //buffer: PSDL_Surface;

-  YPos         : Integer;

-begin

-  if ( DstSurface <> nil ) and ( DifY <> 0 ) then

-  begin

-    //if DifY > 0 then // going up

-    //begin

-    ypos := 0;

-    r1.x := 0;

-    r2.x := 0;

-    r1.w := DstSurface.w;

-    r2.w := DstSurface.w;

-    r1.h := DifY;

-    r2.h := DifY;

-    while ypos < DstSurface.h do

-    begin

-      r1.y := ypos;

-      r2.y := ypos + DifY;

-      SDL_BlitSurface( DstSurface, @r2, DstSurface, @r1 );

-      ypos := ypos + DifY;

-    end;

-    //end

-    //else

-    //begin // Going Down

-    //end;

-  end;

-end;

-

-{procedure SDL_ScrollY(Surface: PSDL_Surface; DifY: integer);

-var

-  r1, r2: TSDL_Rect;

-  buffer: PSDL_Surface;

-begin

-  if (Surface <> nil) and (Dify <> 0) then

-  begin

-    buffer := SDL_CreateRGBSurface(SDL_HWSURFACE, (Surface^.w - DifY) * 2,

-      Surface^.h * 2,

-      Surface^.Format^.BitsPerPixel, 0, 0, 0, 0);

-    if buffer <> nil then

-    begin

-      if (buffer^.format^.BytesPerPixel = 1) then

-        SDL_SetColors(buffer, @Surface^.format^.palette^.colors^[0], 0, 256);

-      r1 := SDLRect(0, DifY, buffer^.w, buffer^.h);

-      r2 := SDLRect(0, 0, buffer^.w, buffer^.h);

-      SDL_BlitSurface(Surface, @r1, buffer, @r2);

-      SDL_BlitSurface(buffer, @r2, Surface, @r2);

-      SDL_FreeSurface(buffer);

-    end;

-  end;

-end;}

-

-procedure SDL_ScrollX( DstSurface : PSDL_Surface; DifX : integer );

-var

-  r1, r2       : TSDL_Rect;

-  buffer       : PSDL_Surface;

-begin

-  if ( DstSurface <> nil ) and ( DifX <> 0 ) then

-  begin

-    buffer := SDL_CreateRGBSurface( SDL_HWSURFACE, ( DstSurface^.w - DifX ) * 2,

-      DstSurface^.h * 2,

-      DstSurface^.Format^.BitsPerPixel,

-      DstSurface^.Format^.RMask,

-      DstSurface^.Format^.GMask,

-      DstSurface^.Format^.BMask,

-      DstSurface^.Format^.AMask );

-    if buffer <> nil then

-    begin

-      if ( buffer^.format^.BytesPerPixel = 1 ) then

-        SDL_SetColors( buffer, @DstSurface^.format^.palette^.colors^[ 0 ], 0, 256 );

-      r1 := SDLRect( DifX, 0, buffer^.w, buffer^.h );

-      r2 := SDLRect( 0, 0, buffer^.w, buffer^.h );

-      SDL_BlitSurface( DstSurface, @r1, buffer, @r2 );

-      SDL_BlitSurface( buffer, @r2, DstSurface, @r2 );

-      SDL_FreeSurface( buffer );

-    end;

-  end;

-end;

-

-procedure SDL_RotateRad( DstSurface, SrcSurface : PSDL_Surface; SrcRect :

-  PSDL_Rect; DestX, DestY, OffsetX, OffsetY : Integer; Angle : Single );

-var

-  aSin, aCos   : Single;

-  MX, MY, DX, DY, NX, NY, SX, SY, OX, OY, Width, Height, TX, TY, RX, RY, ROX, ROY : Integer;

-  Colour, TempTransparentColour : UInt32;

-  MAXX, MAXY   : Integer;

-begin

-  // Rotate the surface to the target surface.

-  TempTransparentColour := SrcSurface.format.colorkey;

-  {if srcRect.w > srcRect.h then

-  begin

-    Width := srcRect.w;

-    Height := srcRect.w;

-  end

-  else

-  begin

-    Width := srcRect.h;

-    Height := srcRect.h;

-  end; }

-

-  maxx := DstSurface.w;

-  maxy := DstSurface.h;

-  aCos := cos( Angle );

-  aSin := sin( Angle );

-

-  Width := round( abs( srcrect.h * acos ) + abs( srcrect.w * asin ) );

-  Height := round( abs( srcrect.h * asin ) + abs( srcrect.w * acos ) );

-

-  OX := Width div 2;

-  OY := Height div 2; ;

-  MX := ( srcRect.x + ( srcRect.x + srcRect.w ) ) div 2;

-  MY := ( srcRect.y + ( srcRect.y + srcRect.h ) ) div 2;

-  ROX := ( -( srcRect.w div 2 ) ) + Offsetx;

-  ROY := ( -( srcRect.h div 2 ) ) + OffsetY;

-  Tx := ox + round( ROX * aSin - ROY * aCos );

-  Ty := oy + round( ROY * aSin + ROX * aCos );

-  SX := 0;

-  for DX := DestX - TX to DestX - TX + ( width ) do

-  begin

-    Inc( SX );

-    SY := 0;

-    for DY := DestY - TY to DestY - TY + ( Height ) do

-    begin

-      RX := SX - OX;

-      RY := SY - OY;

-      NX := round( mx + RX * aSin + RY * aCos ); //

-      NY := round( my + RY * aSin - RX * aCos ); //

-      // Used for testing only

-     //SDL_PutPixel(DestSurface.SDLSurfacePointer,DX,DY,0);

-      if ( ( DX > 0 ) and ( DX < MAXX ) ) and ( ( DY > 0 ) and ( DY < MAXY ) ) then

-      begin

-        if ( NX >= srcRect.x ) and ( NX <= srcRect.x + srcRect.w ) then

-        begin

-          if ( NY >= srcRect.y ) and ( NY <= srcRect.y + srcRect.h ) then

-          begin

-            Colour := SDL_GetPixel( SrcSurface, NX, NY );

-            if Colour <> TempTransparentColour then

-            begin

-              SDL_PutPixel( DstSurface, DX, DY, Colour );

-            end;

-          end;

-        end;

-      end;

-      inc( SY );

-    end;

-  end;

-end;

-

-procedure SDL_RotateDeg( DstSurface, SrcSurface : PSDL_Surface; SrcRect :

-  PSDL_Rect; DestX, DestY, OffsetX, OffsetY : Integer; Angle : Integer );

-begin

-  SDL_RotateRad( DstSurface, SrcSurface, SrcRect, DestX, DestY, OffsetX, OffsetY, DegToRad( Angle ) );

-end;

-

-function ValidateSurfaceRect( DstSurface : PSDL_Surface; dstrect : PSDL_Rect ) : TSDL_Rect;

-var

-  RealRect     : TSDL_Rect;

-  OutOfRange   : Boolean;

-begin

-  OutOfRange := false;

-  if dstrect = nil then

-  begin

-    RealRect.x := 0;

-    RealRect.y := 0;

-    RealRect.w := DstSurface.w;

-    RealRect.h := DstSurface.h;

-  end

-  else

-  begin

-    if dstrect.x < DstSurface.w then

-    begin

-      RealRect.x := dstrect.x;

-    end

-    else if dstrect.x < 0 then

-    begin

-      realrect.x := 0;

-    end

-    else

-    begin

-      OutOfRange := True;

-    end;

-    if dstrect.y < DstSurface.h then

-    begin

-      RealRect.y := dstrect.y;

-    end

-    else if dstrect.y < 0 then

-    begin

-      realrect.y := 0;

-    end

-    else

-    begin

-      OutOfRange := True;

-    end;

-    if OutOfRange = False then

-    begin

-      if realrect.x + dstrect.w <= DstSurface.w then

-      begin

-        RealRect.w := dstrect.w;

-      end

-      else

-      begin

-        RealRect.w := dstrect.w - realrect.x;

-      end;

-      if realrect.y + dstrect.h <= DstSurface.h then

-      begin

-        RealRect.h := dstrect.h;

-      end

-      else

-      begin

-        RealRect.h := dstrect.h - realrect.y;

-      end;

-    end;

-  end;

-  if OutOfRange = False then

-  begin

-    result := realrect;

-  end

-  else

-  begin

-    realrect.w := 0;

-    realrect.h := 0;

-    realrect.x := 0;

-    realrect.y := 0;

-    result := realrect;

-  end;

-end;

-

-procedure SDL_FillRectAdd( DstSurface : PSDL_Surface; dstrect : PSDL_Rect; color : UInt32 );

-var

-  RealRect     : TSDL_Rect;

-  Addr         : pointer;

-  ModX, BPP    : cardinal;

-  x, y, R, G, B, SrcColor : cardinal;

-begin

-  RealRect := ValidateSurfaceRect( DstSurface, DstRect );

-  if ( RealRect.w > 0 ) and ( RealRect.h > 0 ) then

-  begin

-    SDL_LockSurface( DstSurface );

-    BPP := DstSurface.format.BytesPerPixel;

-    with DstSurface^ do

-    begin

-      Addr := pointer( UInt32( pixels ) + UInt32( RealRect.y ) * pitch + UInt32( RealRect.x ) * BPP );

-      ModX := Pitch - UInt32( RealRect.w ) * BPP;

-    end;

-    case DstSurface.format.BitsPerPixel of

-      8 :

-        begin

-          for y := 0 to RealRect.h - 1 do

-          begin

-            for x := 0 to RealRect.w - 1 do

-            begin

-              SrcColor := PUInt32( Addr )^;

-              R := SrcColor and $E0 + Color and $E0;

-              G := SrcColor and $1C + Color and $1C;

-              B := SrcColor and $03 + Color and $03;

-              if R > $E0 then

-                R := $E0;

-              if G > $1C then

-                G := $1C;

-              if B > $03 then

-                B := $03;

-              PUInt8( Addr )^ := R or G or B;

-              inc( UInt32( Addr ), BPP );

-            end;

-            inc( UInt32( Addr ), ModX );

-          end;

-        end;

-      15 :

-        begin

-          for y := 0 to RealRect.h - 1 do

-          begin

-            for x := 0 to RealRect.w - 1 do

-            begin

-              SrcColor := PUInt32( Addr )^;

-              R := SrcColor and $7C00 + Color and $7C00;

-              G := SrcColor and $03E0 + Color and $03E0;

-              B := SrcColor and $001F + Color and $001F;

-              if R > $7C00 then

-                R := $7C00;

-              if G > $03E0 then

-                G := $03E0;

-              if B > $001F then

-                B := $001F;

-              PUInt16( Addr )^ := R or G or B;

-              inc( UInt32( Addr ), BPP );

-            end;

-            inc( UInt32( Addr ), ModX );

-          end;

-        end;

-      16 :

-        begin

-          for y := 0 to RealRect.h - 1 do

-          begin

-            for x := 0 to RealRect.w - 1 do

-            begin

-              SrcColor := PUInt32( Addr )^;

-              R := SrcColor and $F800 + Color and $F800;

-              G := SrcColor and $07C0 + Color and $07C0;

-              B := SrcColor and $001F + Color and $001F;

-              if R > $F800 then

-                R := $F800;

-              if G > $07C0 then

-                G := $07C0;

-              if B > $001F then

-                B := $001F;

-              PUInt16( Addr )^ := R or G or B;

-              inc( UInt32( Addr ), BPP );

-            end;

-            inc( UInt32( Addr ), ModX );

-          end;

-        end;

-      24 :

-        begin

-          for y := 0 to RealRect.h - 1 do

-          begin

-            for x := 0 to RealRect.w - 1 do

-            begin

-              SrcColor := PUInt32( Addr )^;

-              R := SrcColor and $00FF0000 + Color and $00FF0000;

-              G := SrcColor and $0000FF00 + Color and $0000FF00;

-              B := SrcColor and $000000FF + Color and $000000FF;

-              if R > $FF0000 then

-                R := $FF0000;

-              if G > $00FF00 then

-                G := $00FF00;

-              if B > $0000FF then

-                B := $0000FF;

-              PUInt32( Addr )^ := SrcColor and $FF000000 or R or G or B;

-              inc( UInt32( Addr ), BPP );

-            end;

-            inc( UInt32( Addr ), ModX );

-          end;

-        end;

-      32 :

-        begin

-          for y := 0 to RealRect.h - 1 do

-          begin

-            for x := 0 to RealRect.w - 1 do

-            begin

-              SrcColor := PUInt32( Addr )^;

-              R := SrcColor and $00FF0000 + Color and $00FF0000;

-              G := SrcColor and $0000FF00 + Color and $0000FF00;

-              B := SrcColor and $000000FF + Color and $000000FF;

-              if R > $FF0000 then

-                R := $FF0000;

-              if G > $00FF00 then

-                G := $00FF00;

-              if B > $0000FF then

-                B := $0000FF;

-              PUInt32( Addr )^ := R or G or B;

-              inc( UInt32( Addr ), BPP );

-            end;

-            inc( UInt32( Addr ), ModX );

-          end;

-        end;

-    end;

-    SDL_UnlockSurface( DstSurface );

-  end;

-end;

-

-procedure SDL_FillRectSub( DstSurface : PSDL_Surface; dstrect : PSDL_Rect; color : UInt32 );

-var

-  RealRect     : TSDL_Rect;

-  Addr         : pointer;

-  ModX, BPP    : cardinal;

-  x, y, R, G, B, SrcColor : cardinal;

-begin

-  RealRect := ValidateSurfaceRect( DstSurface, DstRect );

-  if ( RealRect.w > 0 ) and ( RealRect.h > 0 ) then

-  begin

-    SDL_LockSurface( DstSurface );

-    BPP := DstSurface.format.BytesPerPixel;

-    with DstSurface^ do

-    begin

-      Addr := pointer( UInt32( pixels ) + UInt32( RealRect.y ) * pitch + UInt32( RealRect.x ) * BPP );

-      ModX := Pitch - UInt32( RealRect.w ) * BPP;

-    end;

-    case DstSurface.format.BitsPerPixel of

-      8 :

-        begin

-          for y := 0 to RealRect.h - 1 do

-          begin

-            for x := 0 to RealRect.w - 1 do

-            begin

-              SrcColor := PUInt32( Addr )^;

-              R := SrcColor and $E0 - Color and $E0;

-              G := SrcColor and $1C - Color and $1C;

-              B := SrcColor and $03 - Color and $03;

-              if R > $E0 then

-                R := 0;

-              if G > $1C then

-                G := 0;

-              if B > $03 then

-                B := 0;

-              PUInt8( Addr )^ := R or G or B;

-              inc( UInt32( Addr ), BPP );

-            end;

-            inc( UInt32( Addr ), ModX );

-          end;

-        end;

-      15 :

-        begin

-          for y := 0 to RealRect.h - 1 do

-          begin

-            for x := 0 to RealRect.w - 1 do

-            begin

-              SrcColor := PUInt32( Addr )^;

-              R := SrcColor and $7C00 - Color and $7C00;

-              G := SrcColor and $03E0 - Color and $03E0;

-              B := SrcColor and $001F - Color and $001F;

-              if R > $7C00 then

-                R := 0;

-              if G > $03E0 then

-                G := 0;

-              if B > $001F then

-                B := 0;

-              PUInt16( Addr )^ := R or G or B;

-              inc( UInt32( Addr ), BPP );

-            end;

-            inc( UInt32( Addr ), ModX );

-          end;

-        end;

-      16 :

-        begin

-          for y := 0 to RealRect.h - 1 do

-          begin

-            for x := 0 to RealRect.w - 1 do

-            begin

-              SrcColor := PUInt32( Addr )^;

-              R := SrcColor and $F800 - Color and $F800;

-              G := SrcColor and $07C0 - Color and $07C0;

-              B := SrcColor and $001F - Color and $001F;

-              if R > $F800 then

-                R := 0;

-              if G > $07C0 then

-                G := 0;

-              if B > $001F then

-                B := 0;

-              PUInt16( Addr )^ := R or G or B;

-              inc( UInt32( Addr ), BPP );

-            end;

-            inc( UInt32( Addr ), ModX );

-          end;

-        end;

-      24 :

-        begin

-          for y := 0 to RealRect.h - 1 do

-          begin

-            for x := 0 to RealRect.w - 1 do

-            begin

-              SrcColor := PUInt32( Addr )^;

-              R := SrcColor and $00FF0000 - Color and $00FF0000;

-              G := SrcColor and $0000FF00 - Color and $0000FF00;

-              B := SrcColor and $000000FF - Color and $000000FF;

-              if R > $FF0000 then

-                R := 0;

-              if G > $00FF00 then

-                G := 0;

-              if B > $0000FF then

-                B := 0;

-              PUInt32( Addr )^ := SrcColor and $FF000000 or R or G or B;

-              inc( UInt32( Addr ), BPP );

-            end;

-            inc( UInt32( Addr ), ModX );

-          end;

-        end;

-      32 :

-        begin

-          for y := 0 to RealRect.h - 1 do

-          begin

-            for x := 0 to RealRect.w - 1 do

-            begin

-              SrcColor := PUInt32( Addr )^;

-              R := SrcColor and $00FF0000 - Color and $00FF0000;

-              G := SrcColor and $0000FF00 - Color and $0000FF00;

-              B := SrcColor and $000000FF - Color and $000000FF;

-              if R > $FF0000 then

-                R := 0;

-              if G > $00FF00 then

-                G := 0;

-              if B > $0000FF then

-                B := 0;

-              PUInt32( Addr )^ := R or G or B;

-              inc( UInt32( Addr ), BPP );

-            end;

-            inc( UInt32( Addr ), ModX );

-          end;

-        end;

-    end;

-    SDL_UnlockSurface( DstSurface );

-  end;

-end;

-

-procedure SDL_GradientFillRect( DstSurface : PSDL_Surface; const Rect : PSDL_Rect; const StartColor, EndColor : TSDL_Color; const Style : TGradientStyle );

-var

-  FBC          : array[ 0..255 ] of Cardinal;

-  // temp vars

-  i, YR, YG, YB, SR, SG, SB, DR, DG, DB : Integer;

-

-  TempStepV, TempStepH : Single;

-  TempLeft, TempTop, TempHeight, TempWidth : integer;

-  TempRect     : TSDL_Rect;

-

-begin

-  // calc FBC

-  YR := StartColor.r;

-  YG := StartColor.g;

-  YB := StartColor.b;

-  SR := YR;

-  SG := YG;

-  SB := YB;

-  DR := EndColor.r - SR;

-  DG := EndColor.g - SG;

-  DB := EndColor.b - SB;

-

-  for i := 0 to 255 do

-  begin

-    FBC[ i ] := SDL_MapRGB( DstSurface.format, YR, YG, YB );

-    YR := SR + round( DR / 255 * i );

-    YG := SG + round( DG / 255 * i );

-    YB := SB + round( DB / 255 * i );

-  end;

-

-  //  if aStyle = 1 then begin

-  TempStepH := Rect.w / 255;

-  TempStepV := Rect.h / 255;

-  TempHeight := Trunc( TempStepV + 1 );

-  TempWidth := Trunc( TempStepH + 1 );

-  TempTop := 0;

-  TempLeft := 0;

-  TempRect.x := Rect.x;

-  TempRect.y := Rect.y;

-  TempRect.h := Rect.h;

-  TempRect.w := Rect.w;

-

-  case Style of

-    gsHorizontal :

-      begin

-        TempRect.h := TempHeight;

-        for i := 0 to 255 do

-        begin

-          TempRect.y := Rect.y + TempTop;

-          SDL_FillRect( DstSurface, @TempRect, FBC[ i ] );

-          TempTop := Trunc( TempStepV * i );

-        end;

-      end;

-    gsVertical :

-      begin

-        TempRect.w := TempWidth;

-        for i := 0 to 255 do

-        begin

-          TempRect.x := Rect.x + TempLeft;

-          SDL_FillRect( DstSurface, @TempRect, FBC[ i ] );

-          TempLeft := Trunc( TempStepH * i );

-        end;

-      end;

-  end;

-end;

-

-procedure SDL_2xBlit( Src, Dest : PSDL_Surface );

-var

-  ReadAddr, WriteAddr, ReadRow, WriteRow : UInt32;

-  SrcPitch, DestPitch, x, y : UInt32;

-begin

-  if ( Src = nil ) or ( Dest = nil ) then

-    exit;

-  if ( Src.w shl 1 ) < Dest.w then

-    exit;

-  if ( Src.h shl 1 ) < Dest.h then

-    exit;

-

-  if SDL_MustLock( Src ) then

-    SDL_LockSurface( Src );

-  if SDL_MustLock( Dest ) then

-    SDL_LockSurface( Dest );

-

-  ReadRow := UInt32( Src.Pixels );

-  WriteRow := UInt32( Dest.Pixels );

-

-  SrcPitch := Src.pitch;

-  DestPitch := Dest.pitch;

-

-  case Src.format.BytesPerPixel of

-    1 : for y := 1 to Src.h do

-      begin

-        ReadAddr := ReadRow;

-        WriteAddr := WriteRow;

-        for x := 1 to Src.w do

-        begin

-          PUInt8( WriteAddr )^ := PUInt8( ReadAddr )^;

-          PUInt8( WriteAddr + 1 )^ := PUInt8( ReadAddr )^;

-          PUInt8( WriteAddr + DestPitch )^ := PUInt8( ReadAddr )^;

-          PUInt8( WriteAddr + DestPitch + 1 )^ := PUInt8( ReadAddr )^;

-          inc( ReadAddr );

-          inc( WriteAddr, 2 );

-        end;

-        inc( UInt32( ReadRow ), SrcPitch );

-        inc( UInt32( WriteRow ), DestPitch * 2 );

-      end;

-    2 : for y := 1 to Src.h do

-      begin

-        ReadAddr := ReadRow;

-        WriteAddr := WriteRow;

-        for x := 1 to Src.w do

-        begin

-          PUInt16( WriteAddr )^ := PUInt16( ReadAddr )^;

-          PUInt16( WriteAddr + 2 )^ := PUInt16( ReadAddr )^;

-          PUInt16( WriteAddr + DestPitch )^ := PUInt16( ReadAddr )^;

-          PUInt16( WriteAddr + DestPitch + 2 )^ := PUInt16( ReadAddr )^;

-          inc( ReadAddr, 2 );

-          inc( WriteAddr, 4 );

-        end;

-        inc( UInt32( ReadRow ), SrcPitch );

-        inc( UInt32( WriteRow ), DestPitch * 2 );

-      end;

-    3 : for y := 1 to Src.h do

-      begin

-        ReadAddr := ReadRow;

-        WriteAddr := WriteRow;

-        for x := 1 to Src.w do

-        begin

-          PUInt32( WriteAddr )^ := ( PUInt32( WriteAddr )^ and $FF000000 ) or ( PUInt32( ReadAddr )^ and $00FFFFFF );

-          PUInt32( WriteAddr + 3 )^ := ( PUInt32( WriteAddr + 3 )^ and $FF000000 ) or ( PUInt32( ReadAddr )^ and $00FFFFFF );

-          PUInt32( WriteAddr + DestPitch )^ := ( PUInt32( WriteAddr + DestPitch )^ and $FF000000 ) or ( PUInt32( ReadAddr )^ and $00FFFFFF );

-          PUInt32( WriteAddr + DestPitch + 3 )^ := ( PUInt32( WriteAddr + DestPitch + 3 )^ and $FF000000 ) or ( PUInt32( ReadAddr )^ and $00FFFFFF );

-          inc( ReadAddr, 3 );

-          inc( WriteAddr, 6 );

-        end;

-        inc( UInt32( ReadRow ), SrcPitch );

-        inc( UInt32( WriteRow ), DestPitch * 2 );

-      end;

-    4 : for y := 1 to Src.h do

-      begin

-        ReadAddr := ReadRow;

-        WriteAddr := WriteRow;

-        for x := 1 to Src.w do

-        begin

-          PUInt32( WriteAddr )^ := PUInt32( ReadAddr )^;

-          PUInt32( WriteAddr + 4 )^ := PUInt32( ReadAddr )^;

-          PUInt32( WriteAddr + DestPitch )^ := PUInt32( ReadAddr )^;

-          PUInt32( WriteAddr + DestPitch + 4 )^ := PUInt32( ReadAddr )^;

-          inc( ReadAddr, 4 );

-          inc( WriteAddr, 8 );

-        end;

-        inc( UInt32( ReadRow ), SrcPitch );

-        inc( UInt32( WriteRow ), DestPitch * 2 );

-      end;

-  end;

-

-  if SDL_MustLock( Src ) then

-    SDL_UnlockSurface( Src );

-  if SDL_MustLock( Dest ) then

-    SDL_UnlockSurface( Dest );

-end;

-

-procedure SDL_Scanline2xBlit( Src, Dest : PSDL_Surface );

-var

-  ReadAddr, WriteAddr, ReadRow, WriteRow : UInt32;

-  SrcPitch, DestPitch, x, y : UInt32;

-begin

-  if ( Src = nil ) or ( Dest = nil ) then

-    exit;

-  if ( Src.w shl 1 ) < Dest.w then

-    exit;

-  if ( Src.h shl 1 ) < Dest.h then

-    exit;

-

-  if SDL_MustLock( Src ) then

-    SDL_LockSurface( Src );

-  if SDL_MustLock( Dest ) then

-    SDL_LockSurface( Dest );

-

-  ReadRow := UInt32( Src.Pixels );

-  WriteRow := UInt32( Dest.Pixels );

-

-  SrcPitch := Src.pitch;

-  DestPitch := Dest.pitch;

-

-  case Src.format.BytesPerPixel of

-    1 : for y := 1 to Src.h do

-      begin

-        ReadAddr := ReadRow;

-        WriteAddr := WriteRow;

-        for x := 1 to Src.w do

-        begin

-          PUInt8( WriteAddr )^ := PUInt8( ReadAddr )^;

-          PUInt8( WriteAddr + 1 )^ := PUInt8( ReadAddr )^;

-          inc( ReadAddr );

-          inc( WriteAddr, 2 );

-        end;

-        inc( UInt32( ReadRow ), SrcPitch );

-        inc( UInt32( WriteRow ), DestPitch * 2 );

-      end;

-    2 : for y := 1 to Src.h do

-      begin

-        ReadAddr := ReadRow;

-        WriteAddr := WriteRow;

-        for x := 1 to Src.w do

-        begin

-          PUInt16( WriteAddr )^ := PUInt16( ReadAddr )^;

-          PUInt16( WriteAddr + 2 )^ := PUInt16( ReadAddr )^;

-          inc( ReadAddr, 2 );

-          inc( WriteAddr, 4 );

-        end;

-        inc( UInt32( ReadRow ), SrcPitch );

-        inc( UInt32( WriteRow ), DestPitch * 2 );

-      end;

-    3 : for y := 1 to Src.h do

-      begin

-        ReadAddr := ReadRow;

-        WriteAddr := WriteRow;

-        for x := 1 to Src.w do

-        begin

-          PUInt32( WriteAddr )^ := ( PUInt32( WriteAddr )^ and $FF000000 ) or ( PUInt32( ReadAddr )^ and $00FFFFFF );

-          PUInt32( WriteAddr + 3 )^ := ( PUInt32( WriteAddr + 3 )^ and $FF000000 ) or ( PUInt32( ReadAddr )^ and $00FFFFFF );

-          inc( ReadAddr, 3 );

-          inc( WriteAddr, 6 );

-        end;

-        inc( UInt32( ReadRow ), SrcPitch );

-        inc( UInt32( WriteRow ), DestPitch * 2 );

-      end;

-    4 : for y := 1 to Src.h do

-      begin

-        ReadAddr := ReadRow;

-        WriteAddr := WriteRow;

-        for x := 1 to Src.w do

-        begin

-          PUInt32( WriteAddr )^ := PUInt32( ReadAddr )^;

-          PUInt32( WriteAddr + 4 )^ := PUInt32( ReadAddr )^;

-          inc( ReadAddr, 4 );

-          inc( WriteAddr, 8 );

-        end;

-        inc( UInt32( ReadRow ), SrcPitch );

-        inc( UInt32( WriteRow ), DestPitch * 2 );

-      end;

-  end;

-

-  if SDL_MustLock( Src ) then

-    SDL_UnlockSurface( Src );

-  if SDL_MustLock( Dest ) then

-    SDL_UnlockSurface( Dest );

-end;

-

-procedure SDL_50Scanline2xBlit( Src, Dest : PSDL_Surface );

-var

-  ReadAddr, WriteAddr, ReadRow, WriteRow : UInt32;

-  SrcPitch, DestPitch, x, y, Color : UInt32;

-begin

-  if ( Src = nil ) or ( Dest = nil ) then

-    exit;

-  if ( Src.w shl 1 ) < Dest.w then

-    exit;

-  if ( Src.h shl 1 ) < Dest.h then

-    exit;

-

-  if SDL_MustLock( Src ) then

-    SDL_LockSurface( Src );

-  if SDL_MustLock( Dest ) then

-    SDL_LockSurface( Dest );

-

-  ReadRow := UInt32( Src.Pixels );

-  WriteRow := UInt32( Dest.Pixels );

-

-  SrcPitch := Src.pitch;

-  DestPitch := Dest.pitch;

-

-  case Src.format.BitsPerPixel of

-    8 : for y := 1 to Src.h do

-      begin

-        ReadAddr := ReadRow;

-        WriteAddr := WriteRow;

-        for x := 1 to Src.w do

-        begin

-          Color := PUInt8( ReadAddr )^;

-          PUInt8( WriteAddr )^ := Color;

-          PUInt8( WriteAddr + 1 )^ := Color;

-          Color := ( Color shr 1 ) and $6D; {%01101101}

-          PUInt8( WriteAddr + DestPitch )^ := Color;

-          PUInt8( WriteAddr + DestPitch + 1 )^ := Color;

-          inc( ReadAddr );

-          inc( WriteAddr, 2 );

-        end;

-        inc( UInt32( ReadRow ), SrcPitch );

-        inc( UInt32( WriteRow ), DestPitch * 2 );

-      end;

-    15 : for y := 1 to Src.h do

-      begin

-        ReadAddr := ReadRow;

-        WriteAddr := WriteRow;

-        for x := 1 to Src.w do

-        begin

-          Color := PUInt16( ReadAddr )^;

-          PUInt16( WriteAddr )^ := Color;

-          PUInt16( WriteAddr + 2 )^ := Color;

-          Color := ( Color shr 1 ) and $3DEF; {%0011110111101111}

-          PUInt16( WriteAddr + DestPitch )^ := Color;

-          PUInt16( WriteAddr + DestPitch + 2 )^ := Color;

-          inc( ReadAddr, 2 );

-          inc( WriteAddr, 4 );

-        end;

-        inc( UInt32( ReadRow ), SrcPitch );

-        inc( UInt32( WriteRow ), DestPitch * 2 );

-      end;

-    16 : for y := 1 to Src.h do

-      begin

-        ReadAddr := ReadRow;

-        WriteAddr := WriteRow;

-        for x := 1 to Src.w do

-        begin

-          Color := PUInt16( ReadAddr )^;

-          PUInt16( WriteAddr )^ := Color;

-          PUInt16( WriteAddr + 2 )^ := Color;

-          Color := ( Color shr 1 ) and $7BEF; {%0111101111101111}

-          PUInt16( WriteAddr + DestPitch )^ := Color;

-          PUInt16( WriteAddr + DestPitch + 2 )^ := Color;

-          inc( ReadAddr, 2 );

-          inc( WriteAddr, 4 );

-        end;

-        inc( UInt32( ReadRow ), SrcPitch );

-        inc( UInt32( WriteRow ), DestPitch * 2 );

-      end;

-    24 : for y := 1 to Src.h do

-      begin

-        ReadAddr := ReadRow;

-        WriteAddr := WriteRow;

-        for x := 1 to Src.w do

-        begin

-          Color := ( PUInt32( WriteAddr )^ and $FF000000 ) or ( PUInt32( ReadAddr )^ and $00FFFFFF );

-          PUInt32( WriteAddr )^ := Color;

-          PUInt32( WriteAddr + 3 )^ := Color;

-          Color := ( Color shr 1 ) and $007F7F7F; {%011111110111111101111111}

-          PUInt32( WriteAddr + DestPitch )^ := Color;

-          PUInt32( WriteAddr + DestPitch + 3 )^ := Color;

-          inc( ReadAddr, 3 );

-          inc( WriteAddr, 6 );

-        end;

-        inc( UInt32( ReadRow ), SrcPitch );

-        inc( UInt32( WriteRow ), DestPitch * 2 );

-      end;

-    32 : for y := 1 to Src.h do

-      begin

-        ReadAddr := ReadRow;

-        WriteAddr := WriteRow;

-        for x := 1 to Src.w do

-        begin

-          Color := PUInt32( ReadAddr )^;

-          PUInt32( WriteAddr )^ := Color;

-          PUInt32( WriteAddr + 4 )^ := Color;

-          Color := ( Color shr 1 ) and $7F7F7F7F;

-          PUInt32( WriteAddr + DestPitch )^ := Color;

-          PUInt32( WriteAddr + DestPitch + 4 )^ := Color;

-          inc( ReadAddr, 4 );

-          inc( WriteAddr, 8 );

-        end;

-        inc( UInt32( ReadRow ), SrcPitch );

-        inc( UInt32( WriteRow ), DestPitch * 2 );

-      end;

-  end;

-

-  if SDL_MustLock( Src ) then

-    SDL_UnlockSurface( Src );

-  if SDL_MustLock( Dest ) then

-    SDL_UnlockSurface( Dest );

-end;

-

-function SDL_PixelTestSurfaceVsRect( SrcSurface1 : PSDL_Surface; SrcRect1 :

-  PSDL_Rect; SrcRect2 : PSDL_Rect; Left1, Top1, Left2, Top2 : integer ) :

-  boolean;

-var

-  Src_Rect1, Src_Rect2 : TSDL_Rect;

-  right1, bottom1 : integer;

-  right2, bottom2 : integer;

-  Scan1Start, {Scan2Start,} ScanWidth, ScanHeight : cardinal;

-  Mod1         : cardinal;

-  Addr1        : cardinal;

-  BPP          : cardinal;

-  Pitch1       : cardinal;

-  TransparentColor1 : cardinal;

-  tx, ty       : cardinal;

-  StartTick    : cardinal;

-  Color1       : cardinal;

-begin

-  Result := false;

-  if SrcRect1 = nil then

-  begin

-    with Src_Rect1 do

-    begin

-      x := 0;

-      y := 0;

-      w := SrcSurface1.w;

-      h := SrcSurface1.h;

-    end;

-  end

-  else

-    Src_Rect1 := SrcRect1^;

-

-  Src_Rect2 := SrcRect2^;

-  with Src_Rect1 do

-  begin

-    Right1 := Left1 + w;

-    Bottom1 := Top1 + h;

-  end;

-  with Src_Rect2 do

-  begin

-    Right2 := Left2 + w;

-    Bottom2 := Top2 + h;

-  end;

-  if ( Left1 >= Right2 ) or ( Right1 <= Left2 ) or ( Top1 >= Bottom2 ) or ( Bottom1 <= Top2 ) then

-    exit;

-  if Left1 <= Left2 then

-  begin

-    // 1. left, 2. right

-    Scan1Start := Src_Rect1.x + Left2 - Left1;

-    //Scan2Start := Src_Rect2.x;

-    ScanWidth := Right1 - Left2;

-    with Src_Rect2 do

-      if ScanWidth > w then

-        ScanWidth := w;

-  end

-  else

-  begin

-    // 1. right, 2. left

-    Scan1Start := Src_Rect1.x;

-    //Scan2Start := Src_Rect2.x + Left1 - Left2;

-    ScanWidth := Right2 - Left1;

-    with Src_Rect1 do

-      if ScanWidth > w then

-        ScanWidth := w;

-  end;

-  with SrcSurface1^ do

-  begin

-    Pitch1 := Pitch;

-    Addr1 := cardinal( Pixels );

-    inc( Addr1, Pitch1 * UInt32( Src_Rect1.y ) );

-    with format^ do

-    begin

-      BPP := BytesPerPixel;

-      TransparentColor1 := colorkey;

-    end;

-  end;

-

-  Mod1 := Pitch1 - ( ScanWidth * BPP );

-

-  inc( Addr1, BPP * Scan1Start );

-

-  if Top1 <= Top2 then

-  begin

-    // 1. up, 2. down

-    ScanHeight := Bottom1 - Top2;

-    if ScanHeight > Src_Rect2.h then

-      ScanHeight := Src_Rect2.h;

-    inc( Addr1, Pitch1 * UInt32( Top2 - Top1 ) );

-  end

-  else

-  begin

-    // 1. down, 2. up

-    ScanHeight := Bottom2 - Top1;

-    if ScanHeight > Src_Rect1.h then

-      ScanHeight := Src_Rect1.h;

-

-  end;

-  case BPP of

-    1 :

-      for ty := 1 to ScanHeight do

-      begin

-        for tx := 1 to ScanWidth do

-        begin

-          if ( PByte( Addr1 )^ <> TransparentColor1 ) then

-          begin

-            Result := true;

-            exit;

-          end;

-          inc( Addr1 );

-

-        end;

-        inc( Addr1, Mod1 );

-

-      end;

-    2 :

-      for ty := 1 to ScanHeight do

-      begin

-        for tx := 1 to ScanWidth do

-        begin

-          if ( PWord( Addr1 )^ <> TransparentColor1 ) then

-          begin

-            Result := true;

-            exit;

-          end;

-          inc( Addr1, 2 );

-

-        end;

-        inc( Addr1, Mod1 );

-

-      end;

-    3 :

-      for ty := 1 to ScanHeight do

-      begin

-        for tx := 1 to ScanWidth do

-        begin

-          Color1 := PLongWord( Addr1 )^ and $00FFFFFF;

-

-          if ( Color1 <> TransparentColor1 )

-            then

-          begin

-            Result := true;

-            exit;

-          end;

-          inc( Addr1, 3 );

-

-        end;

-        inc( Addr1, Mod1 );

-

-      end;

-    4 :

-      for ty := 1 to ScanHeight do

-      begin

-        for tx := 1 to ScanWidth do

-        begin

-          if ( PLongWord( Addr1 )^ <> TransparentColor1 ) then

-          begin

-            Result := true;

-            exit;

-          end;

-          inc( Addr1, 4 );

-

-        end;

-        inc( Addr1, Mod1 );

-

-      end;

-  end;

-end;

-

-procedure SDL_ORSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;

-  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );

-var

-  R, G, B, Pixel1, Pixel2, TransparentColor : cardinal;

-  Src, Dest    : TSDL_Rect;

-  Diff         : integer;

-  SrcAddr, DestAddr : cardinal;

-  WorkX, WorkY : word;

-  SrcMod, DestMod : cardinal;

-  Bits         : cardinal;

-begin

-  if ( SrcSurface = nil ) or ( DestSurface = nil ) then

-    exit; // Remove this to make it faster

-  if ( SrcSurface.Format.BitsPerPixel <> DestSurface.Format.BitsPerPixel ) then

-    exit; // Remove this to make it faster

-  if SrcRect = nil then

-  begin

-    with Src do

-    begin

-      x := 0;

-      y := 0;

-      w := SrcSurface.w;

-      h := SrcSurface.h;

-    end;

-  end

-  else

-    Src := SrcRect^;

-  if DestRect = nil then

-  begin

-    Dest.x := 0;

-    Dest.y := 0;

-  end

-  else

-    Dest := DestRect^;

-  Dest.w := Src.w;

-  Dest.h := Src.h;

-  with DestSurface.Clip_Rect do

-  begin

-    // Source's right side is greater than the dest.cliprect

-    if Dest.x + Src.w > x + w then

-    begin

-      smallint( Src.w ) := x + w - Dest.x;

-      smallint( Dest.w ) := x + w - Dest.x;

-      if smallint( Dest.w ) < 1 then

-        exit;

-    end;

-    // Source's bottom side is greater than the dest.clip

-    if Dest.y + Src.h > y + h then

-    begin

-      smallint( Src.h ) := y + h - Dest.y;

-      smallint( Dest.h ) := y + h - Dest.y;

-      if smallint( Dest.h ) < 1 then

-        exit;

-    end;

-    // Source's left side is less than the dest.clip

-    if Dest.x < x then

-    begin

-      Diff := x - Dest.x;

-      Src.x := Src.x + Diff;

-      smallint( Src.w ) := smallint( Src.w ) - Diff;

-      Dest.x := x;

-      smallint( Dest.w ) := smallint( Dest.w ) - Diff;

-      if smallint( Dest.w ) < 1 then

-        exit;

-    end;

-    // Source's Top side is less than the dest.clip

-    if Dest.y < y then

-    begin

-      Diff := y - Dest.y;

-      Src.y := Src.y + Diff;

-      smallint( Src.h ) := smallint( Src.h ) - Diff;

-      Dest.y := y;

-      smallint( Dest.h ) := smallint( Dest.h ) - Diff;

-      if smallint( Dest.h ) < 1 then

-        exit;

-    end;

-  end;

-  with SrcSurface^ do

-  begin

-    SrcAddr := cardinal( Pixels ) + UInt32( Src.y ) * Pitch + UInt32( Src.x ) *

-      Format.BytesPerPixel;

-    SrcMod := Pitch - Src.w * Format.BytesPerPixel;

-    TransparentColor := Format.colorkey;

-  end;

-  with DestSurface^ do

-  begin

-    DestAddr := cardinal( Pixels ) + UInt32( Dest.y ) * Pitch + UInt32( Dest.x ) *

-      Format.BytesPerPixel;

-    DestMod := Pitch - Dest.w * Format.BytesPerPixel;

-    Bits := Format.BitsPerPixel;

-  end;

-  SDL_LockSurface( SrcSurface );

-  SDL_LockSurface( DestSurface );

-  WorkY := Src.h;

-  case bits of

-    8 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt8( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt8( DestAddr )^;

-              PUInt8( DestAddr )^ := Pixel2 or Pixel1;

-            end;

-            inc( SrcAddr );

-            inc( DestAddr );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    15 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt16( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt16( DestAddr )^;

-

-              PUInt16( DestAddr )^ := Pixel2 or Pixel1;

-

-            end;

-            inc( SrcAddr, 2 );

-            inc( DestAddr, 2 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    16 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt16( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt16( DestAddr )^;

-

-              PUInt16( DestAddr )^ := Pixel2 or Pixel1;

-

-            end;

-            inc( SrcAddr, 2 );

-            inc( DestAddr, 2 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    24 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt32( SrcAddr )^ and $00FFFFFF;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt32( DestAddr )^ and $00FFFFFF;

-

-              PUInt32( DestAddr )^ := PUInt32( DestAddr )^ and $FF000000 or Pixel2 or Pixel1;

-            end;

-            inc( SrcAddr, 3 );

-            inc( DestAddr, 3 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    32 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt32( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt32( DestAddr )^;

-

-              PUInt32( DestAddr )^ := Pixel2 or Pixel1;

-            end;

-            inc( SrcAddr, 4 );

-            inc( DestAddr, 4 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-  end;

-  SDL_UnlockSurface( SrcSurface );

-  SDL_UnlockSurface( DestSurface );

-end;

-

-procedure SDL_ANDSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;

-  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );

-var

-  R, G, B, Pixel1, Pixel2, TransparentColor : cardinal;

-  Src, Dest    : TSDL_Rect;

-  Diff         : integer;

-  SrcAddr, DestAddr : cardinal;

-  WorkX, WorkY : word;

-  SrcMod, DestMod : cardinal;

-  Bits         : cardinal;

-begin

-  if ( SrcSurface = nil ) or ( DestSurface = nil ) then

-    exit; // Remove this to make it faster

-  if ( SrcSurface.Format.BitsPerPixel <> DestSurface.Format.BitsPerPixel ) then

-    exit; // Remove this to make it faster

-  if SrcRect = nil then

-  begin

-    with Src do

-    begin

-      x := 0;

-      y := 0;

-      w := SrcSurface.w;

-      h := SrcSurface.h;

-    end;

-  end

-  else

-    Src := SrcRect^;

-  if DestRect = nil then

-  begin

-    Dest.x := 0;

-    Dest.y := 0;

-  end

-  else

-    Dest := DestRect^;

-  Dest.w := Src.w;

-  Dest.h := Src.h;

-  with DestSurface.Clip_Rect do

-  begin

-    // Source's right side is greater than the dest.cliprect

-    if Dest.x + Src.w > x + w then

-    begin

-      smallint( Src.w ) := x + w - Dest.x;

-      smallint( Dest.w ) := x + w - Dest.x;

-      if smallint( Dest.w ) < 1 then

-        exit;

-    end;

-    // Source's bottom side is greater than the dest.clip

-    if Dest.y + Src.h > y + h then

-    begin

-      smallint( Src.h ) := y + h - Dest.y;

-      smallint( Dest.h ) := y + h - Dest.y;

-      if smallint( Dest.h ) < 1 then

-        exit;

-    end;

-    // Source's left side is less than the dest.clip

-    if Dest.x < x then

-    begin

-      Diff := x - Dest.x;

-      Src.x := Src.x + Diff;

-      smallint( Src.w ) := smallint( Src.w ) - Diff;

-      Dest.x := x;

-      smallint( Dest.w ) := smallint( Dest.w ) - Diff;

-      if smallint( Dest.w ) < 1 then

-        exit;

-    end;

-    // Source's Top side is less than the dest.clip

-    if Dest.y < y then

-    begin

-      Diff := y - Dest.y;

-      Src.y := Src.y + Diff;

-      smallint( Src.h ) := smallint( Src.h ) - Diff;

-      Dest.y := y;

-      smallint( Dest.h ) := smallint( Dest.h ) - Diff;

-      if smallint( Dest.h ) < 1 then

-        exit;

-    end;

-  end;

-  with SrcSurface^ do

-  begin

-    SrcAddr := cardinal( Pixels ) + UInt32( Src.y ) * Pitch + UInt32( Src.x ) *

-      Format.BytesPerPixel;

-    SrcMod := Pitch - Src.w * Format.BytesPerPixel;

-    TransparentColor := Format.colorkey;

-  end;

-  with DestSurface^ do

-  begin

-    DestAddr := cardinal( Pixels ) + UInt32( Dest.y ) * Pitch + UInt32( Dest.x ) *

-      Format.BytesPerPixel;

-    DestMod := Pitch - Dest.w * Format.BytesPerPixel;

-    Bits := Format.BitsPerPixel;

-  end;

-  SDL_LockSurface( SrcSurface );

-  SDL_LockSurface( DestSurface );

-  WorkY := Src.h;

-  case bits of

-    8 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt8( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt8( DestAddr )^;

-              PUInt8( DestAddr )^ := Pixel2 and Pixel1;

-            end;

-            inc( SrcAddr );

-            inc( DestAddr );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    15 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt16( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt16( DestAddr )^;

-

-              PUInt16( DestAddr )^ := Pixel2 and Pixel1;

-

-            end;

-            inc( SrcAddr, 2 );

-            inc( DestAddr, 2 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    16 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt16( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt16( DestAddr )^;

-

-              PUInt16( DestAddr )^ := Pixel2 and Pixel1;

-

-            end;

-            inc( SrcAddr, 2 );

-            inc( DestAddr, 2 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    24 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt32( SrcAddr )^ and $00FFFFFF;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt32( DestAddr )^ and $00FFFFFF;

-

-              PUInt32( DestAddr )^ := PUInt32( DestAddr )^ and $FF000000 or Pixel2 and Pixel1;

-            end;

-            inc( SrcAddr, 3 );

-            inc( DestAddr, 3 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    32 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt32( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt32( DestAddr )^;

-

-              PUInt32( DestAddr )^ := Pixel2 and Pixel1;

-            end;

-            inc( SrcAddr, 4 );

-            inc( DestAddr, 4 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-  end;

-  SDL_UnlockSurface( SrcSurface );

-  SDL_UnlockSurface( DestSurface );

-end;

-

-

-

-procedure SDL_GTSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;

-  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );

-var

-  R, G, B, Pixel1, Pixel2, TransparentColor : cardinal;

-  Src, Dest    : TSDL_Rect;

-  Diff         : integer;

-  SrcAddr, DestAddr : cardinal;

-  WorkX, WorkY : word;

-  SrcMod, DestMod : cardinal;

-  Bits         : cardinal;

-begin

-  if ( SrcSurface = nil ) or ( DestSurface = nil ) then

-    exit; // Remove this to make it faster

-  if ( SrcSurface.Format.BitsPerPixel <> DestSurface.Format.BitsPerPixel ) then

-    exit; // Remove this to make it faster

-  if SrcRect = nil then

-  begin

-    with Src do

-    begin

-      x := 0;

-      y := 0;

-      w := SrcSurface.w;

-      h := SrcSurface.h;

-    end;

-  end

-  else

-    Src := SrcRect^;

-  if DestRect = nil then

-  begin

-    Dest.x := 0;

-    Dest.y := 0;

-  end

-  else

-    Dest := DestRect^;

-  Dest.w := Src.w;

-  Dest.h := Src.h;

-  with DestSurface.Clip_Rect do

-  begin

-    // Source's right side is greater than the dest.cliprect

-    if Dest.x + Src.w > x + w then

-    begin

-      smallint( Src.w ) := x + w - Dest.x;

-      smallint( Dest.w ) := x + w - Dest.x;

-      if smallint( Dest.w ) < 1 then

-        exit;

-    end;

-    // Source's bottom side is greater than the dest.clip

-    if Dest.y + Src.h > y + h then

-    begin

-      smallint( Src.h ) := y + h - Dest.y;

-      smallint( Dest.h ) := y + h - Dest.y;

-      if smallint( Dest.h ) < 1 then

-        exit;

-    end;

-    // Source's left side is less than the dest.clip

-    if Dest.x < x then

-    begin

-      Diff := x - Dest.x;

-      Src.x := Src.x + Diff;

-      smallint( Src.w ) := smallint( Src.w ) - Diff;

-      Dest.x := x;

-      smallint( Dest.w ) := smallint( Dest.w ) - Diff;

-      if smallint( Dest.w ) < 1 then

-        exit;

-    end;

-    // Source's Top side is less than the dest.clip

-    if Dest.y < y then

-    begin

-      Diff := y - Dest.y;

-      Src.y := Src.y + Diff;

-      smallint( Src.h ) := smallint( Src.h ) - Diff;

-      Dest.y := y;

-      smallint( Dest.h ) := smallint( Dest.h ) - Diff;

-      if smallint( Dest.h ) < 1 then

-        exit;

-    end;

-  end;

-  with SrcSurface^ do

-  begin

-    SrcAddr := cardinal( Pixels ) + UInt32( Src.y ) * Pitch + UInt32( Src.x ) *

-      Format.BytesPerPixel;

-    SrcMod := Pitch - Src.w * Format.BytesPerPixel;

-    TransparentColor := Format.colorkey;

-  end;

-  with DestSurface^ do

-  begin

-    DestAddr := cardinal( Pixels ) + UInt32( Dest.y ) * Pitch + UInt32( Dest.x ) *

-      Format.BytesPerPixel;

-    DestMod := Pitch - Dest.w * Format.BytesPerPixel;

-    Bits := Format.BitsPerPixel;

-  end;

-  SDL_LockSurface( SrcSurface );

-  SDL_LockSurface( DestSurface );

-  WorkY := Src.h;

-  case bits of

-    8 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt8( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt8( DestAddr )^;

-              if Pixel2 > 0 then

-              begin

-                if Pixel2 and $E0 > Pixel1 and $E0 then

-                  R := Pixel2 and $E0

-                else

-                  R := Pixel1 and $E0;

-                if Pixel2 and $1C > Pixel1 and $1C then

-                  G := Pixel2 and $1C

-                else

-                  G := Pixel1 and $1C;

-                if Pixel2 and $03 > Pixel1 and $03 then

-                  B := Pixel2 and $03

-                else

-                  B := Pixel1 and $03;

-

-                if R > $E0 then

-                  R := $E0;

-                if G > $1C then

-                  G := $1C;

-                if B > $03 then

-                  B := $03;

-                PUInt8( DestAddr )^ := R or G or B;

-              end

-              else

-                PUInt8( DestAddr )^ := Pixel1;

-            end;

-            inc( SrcAddr );

-            inc( DestAddr );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    15 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt16( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt16( DestAddr )^;

-              if Pixel2 > 0 then

-              begin

-

-                if Pixel2 and $7C00 > Pixel1 and $7C00 then

-                  R := Pixel2 and $7C00

-                else

-                  R := Pixel1 and $7C00;

-                if Pixel2 and $03E0 > Pixel1 and $03E0 then

-                  G := Pixel2 and $03E0

-                else

-                  G := Pixel1 and $03E0;

-                if Pixel2 and $001F > Pixel1 and $001F then

-                  B := Pixel2 and $001F

-                else

-                  B := Pixel1 and $001F;

-

-                PUInt16( DestAddr )^ := R or G or B;

-              end

-              else

-                PUInt16( DestAddr )^ := Pixel1;

-            end;

-            inc( SrcAddr, 2 );

-            inc( DestAddr, 2 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    16 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt16( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt16( DestAddr )^;

-              if Pixel2 > 0 then

-              begin

-

-                if Pixel2 and $F800 > Pixel1 and $F800 then

-                  R := Pixel2 and $F800

-                else

-                  R := Pixel1 and $F800;

-                if Pixel2 and $07E0 > Pixel1 and $07E0 then

-                  G := Pixel2 and $07E0

-                else

-                  G := Pixel1 and $07E0;

-                if Pixel2 and $001F > Pixel1 and $001F then

-                  B := Pixel2 and $001F

-                else

-                  B := Pixel1 and $001F;

-

-                PUInt16( DestAddr )^ := R or G or B;

-              end

-              else

-                PUInt16( DestAddr )^ := Pixel1;

-            end;

-            inc( SrcAddr, 2 );

-            inc( DestAddr, 2 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    24 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt32( SrcAddr )^ and $00FFFFFF;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt32( DestAddr )^ and $00FFFFFF;

-              if Pixel2 > 0 then

-              begin

-

-                if Pixel2 and $FF0000 > Pixel1 and $FF0000 then

-                  R := Pixel2 and $FF0000

-                else

-                  R := Pixel1 and $FF0000;

-                if Pixel2 and $00FF00 > Pixel1 and $00FF00 then

-                  G := Pixel2 and $00FF00

-                else

-                  G := Pixel1 and $00FF00;

-                if Pixel2 and $0000FF > Pixel1 and $0000FF then

-                  B := Pixel2 and $0000FF

-                else

-                  B := Pixel1 and $0000FF;

-

-                PUInt32( DestAddr )^ := PUInt32( DestAddr )^ and $FF000000 or ( R or G or B );

-              end

-              else

-                PUInt32( DestAddr )^ := PUInt32( DestAddr )^ and $FF000000 or Pixel1;

-            end;

-            inc( SrcAddr, 3 );

-            inc( DestAddr, 3 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    32 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt32( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt32( DestAddr )^;

-              if Pixel2 > 0 then

-              begin

-

-                if Pixel2 and $FF0000 > Pixel1 and $FF0000 then

-                  R := Pixel2 and $FF0000

-                else

-                  R := Pixel1 and $FF0000;

-                if Pixel2 and $00FF00 > Pixel1 and $00FF00 then

-                  G := Pixel2 and $00FF00

-                else

-                  G := Pixel1 and $00FF00;

-                if Pixel2 and $0000FF > Pixel1 and $0000FF then

-                  B := Pixel2 and $0000FF

-                else

-                  B := Pixel1 and $0000FF;

-

-                PUInt32( DestAddr )^ := R or G or B;

-              end

-              else

-                PUInt32( DestAddr )^ := Pixel1;

-            end;

-            inc( SrcAddr, 4 );

-            inc( DestAddr, 4 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-  end;

-  SDL_UnlockSurface( SrcSurface );

-  SDL_UnlockSurface( DestSurface );

-end;

-

-

-procedure SDL_LTSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;

-  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );

-var

-  R, G, B, Pixel1, Pixel2, TransparentColor : cardinal;

-  Src, Dest    : TSDL_Rect;

-  Diff         : integer;

-  SrcAddr, DestAddr : cardinal;

-  WorkX, WorkY : word;

-  SrcMod, DestMod : cardinal;

-  Bits         : cardinal;

-begin

-  if ( SrcSurface = nil ) or ( DestSurface = nil ) then

-    exit; // Remove this to make it faster

-  if ( SrcSurface.Format.BitsPerPixel <> DestSurface.Format.BitsPerPixel ) then

-    exit; // Remove this to make it faster

-  if SrcRect = nil then

-  begin

-    with Src do

-    begin

-      x := 0;

-      y := 0;

-      w := SrcSurface.w;

-      h := SrcSurface.h;

-    end;

-  end

-  else

-    Src := SrcRect^;

-  if DestRect = nil then

-  begin

-    Dest.x := 0;

-    Dest.y := 0;

-  end

-  else

-    Dest := DestRect^;

-  Dest.w := Src.w;

-  Dest.h := Src.h;

-  with DestSurface.Clip_Rect do

-  begin

-    // Source's right side is greater than the dest.cliprect

-    if Dest.x + Src.w > x + w then

-    begin

-      smallint( Src.w ) := x + w - Dest.x;

-      smallint( Dest.w ) := x + w - Dest.x;

-      if smallint( Dest.w ) < 1 then

-        exit;

-    end;

-    // Source's bottom side is greater than the dest.clip

-    if Dest.y + Src.h > y + h then

-    begin

-      smallint( Src.h ) := y + h - Dest.y;

-      smallint( Dest.h ) := y + h - Dest.y;

-      if smallint( Dest.h ) < 1 then

-        exit;

-    end;

-    // Source's left side is less than the dest.clip

-    if Dest.x < x then

-    begin

-      Diff := x - Dest.x;

-      Src.x := Src.x + Diff;

-      smallint( Src.w ) := smallint( Src.w ) - Diff;

-      Dest.x := x;

-      smallint( Dest.w ) := smallint( Dest.w ) - Diff;

-      if smallint( Dest.w ) < 1 then

-        exit;

-    end;

-    // Source's Top side is less than the dest.clip

-    if Dest.y < y then

-    begin

-      Diff := y - Dest.y;

-      Src.y := Src.y + Diff;

-      smallint( Src.h ) := smallint( Src.h ) - Diff;

-      Dest.y := y;

-      smallint( Dest.h ) := smallint( Dest.h ) - Diff;

-      if smallint( Dest.h ) < 1 then

-        exit;

-    end;

-  end;

-  with SrcSurface^ do

-  begin

-    SrcAddr := cardinal( Pixels ) + UInt32( Src.y ) * Pitch + UInt32( Src.x ) *

-      Format.BytesPerPixel;

-    SrcMod := Pitch - Src.w * Format.BytesPerPixel;

-    TransparentColor := Format.colorkey;

-  end;

-  with DestSurface^ do

-  begin

-    DestAddr := cardinal( Pixels ) + UInt32( Dest.y ) * Pitch + UInt32( Dest.x ) *

-      Format.BytesPerPixel;

-    DestMod := Pitch - Dest.w * Format.BytesPerPixel;

-    Bits := Format.BitsPerPixel;

-  end;

-  SDL_LockSurface( SrcSurface );

-  SDL_LockSurface( DestSurface );

-  WorkY := Src.h;

-  case bits of

-    8 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt8( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt8( DestAddr )^;

-              if Pixel2 > 0 then

-              begin

-                if Pixel2 and $E0 < Pixel1 and $E0 then

-                  R := Pixel2 and $E0

-                else

-                  R := Pixel1 and $E0;

-                if Pixel2 and $1C < Pixel1 and $1C then

-                  G := Pixel2 and $1C

-                else

-                  G := Pixel1 and $1C;

-                if Pixel2 and $03 < Pixel1 and $03 then

-                  B := Pixel2 and $03

-                else

-                  B := Pixel1 and $03;

-

-                if R > $E0 then

-                  R := $E0;

-                if G > $1C then

-                  G := $1C;

-                if B > $03 then

-                  B := $03;

-                PUInt8( DestAddr )^ := R or G or B;

-              end

-              else

-                PUInt8( DestAddr )^ := Pixel1;

-            end;

-            inc( SrcAddr );

-            inc( DestAddr );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    15 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt16( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt16( DestAddr )^;

-              if Pixel2 > 0 then

-              begin

-

-                if Pixel2 and $7C00 < Pixel1 and $7C00 then

-                  R := Pixel2 and $7C00

-                else

-                  R := Pixel1 and $7C00;

-                if Pixel2 and $03E0 < Pixel1 and $03E0 then

-                  G := Pixel2 and $03E0

-                else

-                  G := Pixel1 and $03E0;

-                if Pixel2 and $001F < Pixel1 and $001F then

-                  B := Pixel2 and $001F

-                else

-                  B := Pixel1 and $001F;

-

-                PUInt16( DestAddr )^ := R or G or B;

-              end

-              else

-                PUInt16( DestAddr )^ := Pixel1;

-            end;

-            inc( SrcAddr, 2 );

-            inc( DestAddr, 2 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    16 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt16( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt16( DestAddr )^;

-              if Pixel2 > 0 then

-              begin

-

-                if Pixel2 and $F800 < Pixel1 and $F800 then

-                  R := Pixel2 and $F800

-                else

-                  R := Pixel1 and $F800;

-                if Pixel2 and $07E0 < Pixel1 and $07E0 then

-                  G := Pixel2 and $07E0

-                else

-                  G := Pixel1 and $07E0;

-                if Pixel2 and $001F < Pixel1 and $001F then

-                  B := Pixel2 and $001F

-                else

-                  B := Pixel1 and $001F;

-

-                PUInt16( DestAddr )^ := R or G or B;

-              end

-              else

-                PUInt16( DestAddr )^ := Pixel1;

-            end;

-            inc( SrcAddr, 2 );

-            inc( DestAddr, 2 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    24 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt32( SrcAddr )^ and $00FFFFFF;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt32( DestAddr )^ and $00FFFFFF;

-              if Pixel2 > 0 then

-              begin

-

-                if Pixel2 and $FF0000 < Pixel1 and $FF0000 then

-                  R := Pixel2 and $FF0000

-                else

-                  R := Pixel1 and $FF0000;

-                if Pixel2 and $00FF00 < Pixel1 and $00FF00 then

-                  G := Pixel2 and $00FF00

-                else

-                  G := Pixel1 and $00FF00;

-                if Pixel2 and $0000FF < Pixel1 and $0000FF then

-                  B := Pixel2 and $0000FF

-                else

-                  B := Pixel1 and $0000FF;

-

-                PUInt32( DestAddr )^ := PUInt32( DestAddr )^ and $FF000000 or ( R or G or B );

-              end

-              else

-                PUInt32( DestAddr )^ := PUInt32( DestAddr )^ and $FF000000 or Pixel1;

-            end;

-            inc( SrcAddr, 3 );

-            inc( DestAddr, 3 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-    32 :

-      begin

-        repeat

-          WorkX := Src.w;

-          repeat

-            Pixel1 := PUInt32( SrcAddr )^;

-            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then

-            begin

-              Pixel2 := PUInt32( DestAddr )^;

-              if Pixel2 > 0 then

-              begin

-

-                if Pixel2 and $FF0000 < Pixel1 and $FF0000 then

-                  R := Pixel2 and $FF0000

-                else

-                  R := Pixel1 and $FF0000;

-                if Pixel2 and $00FF00 < Pixel1 and $00FF00 then

-                  G := Pixel2 and $00FF00

-                else

-                  G := Pixel1 and $00FF00;

-                if Pixel2 and $0000FF < Pixel1 and $0000FF then

-                  B := Pixel2 and $0000FF

-                else

-                  B := Pixel1 and $0000FF;

-

-                PUInt32( DestAddr )^ := R or G or B;

-              end

-              else

-                PUInt32( DestAddr )^ := Pixel1;

-            end;

-            inc( SrcAddr, 4 );

-            inc( DestAddr, 4 );

-            dec( WorkX );

-          until WorkX = 0;

-          inc( SrcAddr, SrcMod );

-          inc( DestAddr, DestMod );

-          dec( WorkY );

-        until WorkY = 0;

-      end;

-  end;

-  SDL_UnlockSurface( SrcSurface );

-  SDL_UnlockSurface( DestSurface );

-end;

-

-// Will clip the x1,x2,y1,x2 params to the ClipRect provided

-

-function SDL_ClipLine( var x1, y1, x2, y2 : Integer; ClipRect : PSDL_Rect ) : boolean;

-var

-  tflag, flag1, flag2 : word;

-  txy, xedge, yedge : Integer;

-  slope        : single;

-

-  function ClipCode( x, y : Integer ) : word;

-  begin

-    Result := 0;

-    if x < ClipRect.x then

-      Result := 1;

-    if x >= ClipRect.w + ClipRect.x then

-      Result := Result or 2;

-    if y < ClipRect.y then

-      Result := Result or 4;

-    if y >= ClipRect.h + ClipRect.y then

-      Result := Result or 8;

-  end;

-

-begin

-  flag1 := ClipCode( x1, y1 );

-  flag2 := ClipCode( x2, y2 );

-  result := true;

-

-  while true do

-  begin

-    if ( flag1 or flag2 ) = 0 then

-      Exit; // all in

-

-    if ( flag1 and flag2 ) <> 0 then

-    begin

-      result := false;

-      Exit; // all out

-    end;

-

-    if flag2 = 0 then

-    begin

-      txy := x1; x1 := x2; x2 := txy;

-      txy := y1; y1 := y2; y2 := txy;

-      tflag := flag1; flag1 := flag2; flag2 := tflag;

-    end;

-

-    if ( flag2 and 3 ) <> 0 then

-    begin

-      if ( flag2 and 1 ) <> 0 then

-        xedge := ClipRect.x

-      else

-        xedge := ClipRect.w + ClipRect.x - 1; // back 1 pixel otherwise we end up in a loop

-

-      slope := ( y2 - y1 ) / ( x2 - x1 );

-      y2 := y1 + Round( slope * ( xedge - x1 ) );

-      x2 := xedge;

-    end

-    else

-    begin

-      if ( flag2 and 4 ) <> 0 then

-        yedge := ClipRect.y

-      else

-        yedge := ClipRect.h + ClipRect.y - 1; // up 1 pixel otherwise we end up in a loop

-

-      slope := ( x2 - x1 ) / ( y2 - y1 );

-      x2 := x1 + Round( slope * ( yedge - y1 ) );

-      y2 := yedge;

-    end;

-

-    flag2 := ClipCode( x2, y2 );

-  end;

-end;

-

-end.

-

+unit sdlutils;
+{
+  $Id: sdlutils.pas,v 1.5 2006/11/19 18:56:44 savage Exp $
+
+}
+{******************************************************************************}
+{                                                                              }
+{       Borland Delphi SDL - Simple DirectMedia Layer                          }
+{                SDL Utility functions                                         }
+{                                                                              }
+{                                                                              }
+{ The initial developer of this Pascal code was :                              }
+{ Tom Jones <tigertomjones@gmx.de>                                             }
+{                                                                              }
+{ Portions created by Tom Jones are                                            }
+{ Copyright (C) 2000 - 2001 Tom Jones.                                         }
+{                                                                              }
+{                                                                              }
+{ Contributor(s)                                                               }
+{ --------------                                                               }
+{ Dominique Louis <Dominique@SavageSoftware.com.au>                            }
+{ Róbert Kisnémeth <mikrobi@freemail.hu>                                       }
+{                                                                              }
+{ Obtained through:                                                            }
+{ Joint Endeavour of Delphi Innovators ( Project JEDI )                        }
+{                                                                              }
+{ You may retrieve the latest version of this file at the Project              }
+{ JEDI home page, located at http://delphi-jedi.org                            }
+{                                                                              }
+{ The contents of this file are used with permission, subject to               }
+{ the Mozilla Public License Version 1.1 (the "License"); you may              }
+{ not use this file except in compliance with the License. You may             }
+{ obtain a copy of the License at                                              }
+{ http://www.mozilla.org/MPL/MPL-1.1.html                                      }
+{                                                                              }
+{ Software distributed under the License is distributed on an                  }
+{ "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or               }
+{ implied. See the License for the specific language governing                 }
+{ rights and limitations under the License.                                    }
+{                                                                              }
+{ Description                                                                  }
+{ -----------                                                                  }
+{   Helper functions...                                                        }
+{                                                                              }
+{                                                                              }
+{ Requires                                                                     }
+{ --------                                                                     }
+{   SDL.dll on Windows platforms                                               }
+{   libSDL-1.1.so.0 on Linux platform                                          }
+{                                                                              }
+{ Programming Notes                                                            }
+{ -----------------                                                            }
+{                                                                              }
+{                                                                              }
+{                                                                              }
+{                                                                              }
+{ Revision History                                                             }
+{ ----------------                                                             }
+{               2000 - TJ : Initial creation                                   }
+{                                                                              }
+{   July   13   2001 - DL : Added PutPixel and GetPixel routines.              }
+{                                                                              }
+{   Sept   14   2001 - RK : Added flipping routines.                           }
+{                                                                              }
+{   Sept   19   2001 - RK : Added PutPixel & line drawing & blitting with ADD  }
+{                           effect. Fixed a bug in SDL_PutPixel & SDL_GetPixel }
+{                           Added PSDLRect()                                   }
+{   Sept   22   2001 - DL : Removed need for Windows.pas by defining types here}
+{                           Also removed by poor attempt or a dialog box       }
+{                                                                              }
+{   Sept   25   2001 - RK : Added PixelTest, NewPutPixel, SubPixel, SubLine,   }
+{                           SubSurface, MonoSurface & TexturedSurface          }
+{                                                                              }
+{   Sept   26   2001 - DL : Made change so that it refers to native Pascal     }
+{                           types rather that Windows types. This makes it more}
+{                           portable to Linix.                                 }
+{                                                                              }
+{   Sept   27   2001 - RK : SDLUtils now can be compiled with FreePascal       }
+{                                                                              }
+{   Oct    27   2001 - JF : Added ScrollY function                             }
+{                                                                              }
+{   Jan    21   2002 - RK : Added SDL_ZoomSurface and SDL_WarpSurface          }
+{                                                                              }
+{   Mar    28   2002 - JF : Added SDL_RotateSurface                            }
+{                                                                              }
+{   May    13   2002 - RK : Improved SDL_FillRectAdd & SDL_FillRectSub         }
+{                                                                              }
+{   May    27   2002 - YS : GradientFillRect function                          }
+{                                                                              }
+{   May    30   2002 - RK : Added SDL_2xBlit, SDL_Scanline2xBlit               }
+{                           & SDL_50Scanline2xBlit                             }
+{                                                                              }
+{  June    12   2002 - RK : Added SDL_PixelTestSurfaceVsRect                   }
+{                                                                              }
+{  June    12   2002 - JF : Updated SDL_PixelTestSurfaceVsRect                 }
+{                                                                              }
+{ November  9   2002 - JF : Added Jason's boolean Surface functions            }
+{                                                                              }
+{ December 10   2002 - DE : Added Dean's SDL_ClipLine function                 }
+{                                                                              }
+{    April 26   2003 - SS : Incorporated JF's changes to SDL_ClipLine          }
+{                           Fixed SDL_ClipLine bug for non-zero cliprect x, y  }
+{                           Added overloaded SDL_DrawLine for dashed lines     }
+{                                                                              }
+{******************************************************************************}
+{
+  $Log: sdlutils.pas,v $
+  Revision 1.5  2006/11/19 18:56:44  savage
+  Removed Hints and Warnings.
+
+  Revision 1.4  2004/06/02 19:38:53  savage
+  Changes to SDL_GradientFillRect as suggested by
+  Ángel Eduardo García Hernández.  Many thanks.
+
+  Revision 1.3  2004/05/29 23:11:54  savage
+  Changes to SDL_ScaleSurfaceRect as suggested by
+  Ángel Eduardo García Hernández to fix a colour issue with the function. Many thanks.
+
+  Revision 1.2  2004/02/14 00:23:39  savage
+  As UNIX is defined in jedi-sdl.inc this will be used to check linux compatability as well. Units have been changed to reflect this change.
+
+  Revision 1.1  2004/02/05 00:08:20  savage
+  Module 1.0 release
+
+
+}
+
+interface
+
+{$I jedi-sdl.inc}
+
+uses
+{$IFDEF UNIX}
+  Types,
+  Xlib,
+{$ENDIF}
+  SysUtils,
+  sdl;
+
+type
+  TGradientStyle = ( gsHorizontal, gsVertical );
+
+// Pixel procedures
+function SDL_PixelTest( SrcSurface1 : PSDL_Surface; SrcRect1 : PSDL_Rect; SrcSurface2 :
+  PSDL_Surface; SrcRect2 : PSDL_Rect; Left1, Top1, Left2, Top2 : integer ) : Boolean;
+
+function SDL_GetPixel( SrcSurface : PSDL_Surface; x : integer; y : integer ) : Uint32;
+
+procedure SDL_PutPixel( DstSurface : PSDL_Surface; x : integer; y : integer; pixel :
+  Uint32 );
+
+procedure SDL_AddPixel( DstSurface : PSDL_Surface; x : cardinal; y : cardinal; Color :
+  cardinal );
+
+procedure SDL_SubPixel( DstSurface : PSDL_Surface; x : cardinal; y : cardinal; Color :
+  cardinal );
+
+// Line procedures
+procedure SDL_DrawLine( DstSurface : PSDL_Surface; x1, y1, x2, y2 : integer; Color :
+  cardinal ); overload;
+
+procedure SDL_DrawLine( DstSurface : PSDL_Surface; x1, y1, x2, y2 : integer; Color :
+  cardinal; DashLength, DashSpace : byte ); overload;
+
+procedure SDL_AddLine( DstSurface : PSDL_Surface; x1, y1, x2, y2 : integer; Color :
+  cardinal );
+
+procedure SDL_SubLine( DstSurface : PSDL_Surface; x1, y1, x2, y2 : integer; Color :
+  cardinal );
+
+// Surface procedures
+procedure SDL_AddSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;
+  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );
+
+procedure SDL_SubSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;
+  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );
+
+procedure SDL_MonoSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;
+  DestSurface : PSDL_Surface; DestRect : PSDL_Rect; Color : cardinal );
+
+procedure SDL_TexturedSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;
+  DestSurface : PSDL_Surface; DestRect : PSDL_Rect; Texture : PSDL_Surface;
+  TextureRect : PSDL_Rect );
+
+procedure SDL_ZoomSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect; DstSurface : PSDL_Surface; DstRect : PSDL_Rect );
+
+procedure SDL_WarpSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect; DstSurface : PSDL_Surface; UL, UR, LR, LL : PPoint );
+
+// Flip procedures
+procedure SDL_FlipRectH( DstSurface : PSDL_Surface; Rect : PSDL_Rect );
+
+procedure SDL_FlipRectV( DstSurface : PSDL_Surface; Rect : PSDL_Rect );
+
+function PSDLRect( aLeft, aTop, aWidth, aHeight : integer ) : PSDL_Rect;
+
+function SDLRect( aLeft, aTop, aWidth, aHeight : integer ) : TSDL_Rect; overload;
+
+function SDLRect( aRect : TRect ) : TSDL_Rect; overload;
+
+function SDL_ScaleSurfaceRect( SrcSurface : PSDL_Surface; SrcX1, SrcY1, SrcW, SrcH,
+  Width, Height : integer ) : PSDL_Surface;
+
+procedure SDL_ScrollY( DstSurface : PSDL_Surface; DifY : integer );
+
+procedure SDL_ScrollX( DstSurface : PSDL_Surface; DifX : integer );
+
+procedure SDL_RotateDeg( DstSurface, SrcSurface : PSDL_Surface; SrcRect :
+  PSDL_Rect; DestX, DestY, OffsetX, OffsetY : Integer; Angle : Integer );
+
+procedure SDL_RotateRad( DstSurface, SrcSurface : PSDL_Surface; SrcRect :
+  PSDL_Rect; DestX, DestY, OffsetX, OffsetY : Integer; Angle : Single );
+
+function ValidateSurfaceRect( DstSurface : PSDL_Surface; dstrect : PSDL_Rect ) : TSDL_Rect;
+
+// Fill Rect routine
+procedure SDL_FillRectAdd( DstSurface : PSDL_Surface; dstrect : PSDL_Rect; color : UInt32 );
+
+procedure SDL_FillRectSub( DstSurface : PSDL_Surface; dstrect : PSDL_Rect; color : UInt32 );
+
+procedure SDL_GradientFillRect( DstSurface : PSDL_Surface; const Rect : PSDL_Rect; const StartColor, EndColor : TSDL_Color; const Style : TGradientStyle );
+
+// NOTE for All SDL_2xblit... function : the dest surface must be 2x of the source surface!
+procedure SDL_2xBlit( Src, Dest : PSDL_Surface );
+
+procedure SDL_Scanline2xBlit( Src, Dest : PSDL_Surface );
+
+procedure SDL_50Scanline2xBlit( Src, Dest : PSDL_Surface );
+
+//
+function SDL_PixelTestSurfaceVsRect( SrcSurface1 : PSDL_Surface; SrcRect1 :
+  PSDL_Rect; SrcRect2 : PSDL_Rect; Left1, Top1, Left2, Top2 : integer ) :
+  boolean;
+
+// Jason's boolean Surface functions
+procedure SDL_ORSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;
+  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );
+
+procedure SDL_ANDSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;
+  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );
+
+
+procedure SDL_GTSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;
+  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );
+
+procedure SDL_LTSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;
+  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );
+
+function SDL_ClipLine( var x1, y1, x2, y2 : Integer; ClipRect : PSDL_Rect ) : boolean;
+
+implementation
+
+uses
+  Math;
+
+function SDL_PixelTest( SrcSurface1 : PSDL_Surface; SrcRect1 : PSDL_Rect; SrcSurface2 :
+  PSDL_Surface; SrcRect2 : PSDL_Rect; Left1, Top1, Left2, Top2 : integer ) : boolean;
+var
+  Src_Rect1, Src_Rect2 : TSDL_Rect;
+  right1, bottom1 : integer;
+  right2, bottom2 : integer;
+  Scan1Start, Scan2Start, ScanWidth, ScanHeight : cardinal;
+  Mod1, Mod2   : cardinal;
+  Addr1, Addr2 : cardinal;
+  BPP          : cardinal;
+  Pitch1, Pitch2 : cardinal;
+  TransparentColor1, TransparentColor2 : cardinal;
+  tx, ty       : cardinal;
+// StartTick    : cardinal; // Auto Removed, Unused Variable
+  Color1, Color2 : cardinal;
+begin
+  Result := false;
+  if SrcRect1 = nil then
+  begin
+    with Src_Rect1 do
+    begin
+      x := 0;
+      y := 0;
+      w := SrcSurface1.w;
+      h := SrcSurface1.h;
+    end;
+  end
+  else
+    Src_Rect1 := SrcRect1^;
+  if SrcRect2 = nil then
+  begin
+    with Src_Rect2 do
+    begin
+      x := 0;
+      y := 0;
+      w := SrcSurface2.w;
+      h := SrcSurface2.h;
+    end;
+  end
+  else
+    Src_Rect2 := SrcRect2^;
+  with Src_Rect1 do
+  begin
+    Right1 := Left1 + w;
+    Bottom1 := Top1 + h;
+  end;
+  with Src_Rect2 do
+  begin
+    Right2 := Left2 + w;
+    Bottom2 := Top2 + h;
+  end;
+  if ( Left1 >= Right2 ) or ( Right1 <= Left2 ) or ( Top1 >= Bottom2 ) or ( Bottom1 <=
+    Top2 ) then
+    exit;
+  if Left1 <= Left2 then
+  begin
+    // 1. left, 2. right
+    Scan1Start := Src_Rect1.x + Left2 - Left1;
+    Scan2Start := Src_Rect2.x;
+    ScanWidth := Right1 - Left2;
+    with Src_Rect2 do
+      if ScanWidth > w then
+        ScanWidth := w;
+  end
+  else
+  begin
+    // 1. right, 2. left
+    Scan1Start := Src_Rect1.x;
+    Scan2Start := Src_Rect2.x + Left1 - Left2;
+    ScanWidth := Right2 - Left1;
+    with Src_Rect1 do
+      if ScanWidth > w then
+        ScanWidth := w;
+  end;
+  with SrcSurface1^ do
+  begin
+    Pitch1 := Pitch;
+    Addr1 := cardinal( Pixels );
+    inc( Addr1, Pitch1 * UInt32( Src_Rect1.y ) );
+    with format^ do
+    begin
+      BPP := BytesPerPixel;
+      TransparentColor1 := colorkey;
+    end;
+  end;
+  with SrcSurface2^ do
+  begin
+    TransparentColor2 := format.colorkey;
+    Pitch2 := Pitch;
+    Addr2 := cardinal( Pixels );
+    inc( Addr2, Pitch2 * UInt32( Src_Rect2.y ) );
+  end;
+  Mod1 := Pitch1 - ( ScanWidth * BPP );
+  Mod2 := Pitch2 - ( ScanWidth * BPP );
+  inc( Addr1, BPP * Scan1Start );
+  inc( Addr2, BPP * Scan2Start );
+  if Top1 <= Top2 then
+  begin
+    // 1. up, 2. down
+    ScanHeight := Bottom1 - Top2;
+    if ScanHeight > Src_Rect2.h then
+      ScanHeight := Src_Rect2.h;
+    inc( Addr1, Pitch1 * UInt32( Top2 - Top1 ) );
+  end
+  else
+  begin
+    // 1. down, 2. up
+    ScanHeight := Bottom2 - Top1;
+    if ScanHeight > Src_Rect1.h then
+      ScanHeight := Src_Rect1.h;
+    inc( Addr2, Pitch2 * UInt32( Top1 - Top2 ) );
+  end;
+  case BPP of
+    1 :
+      for ty := 1 to ScanHeight do
+      begin
+        for tx := 1 to ScanWidth do
+        begin
+          if ( PByte( Addr1 )^ <> TransparentColor1 ) and ( PByte( Addr2 )^ <>
+            TransparentColor2 ) then
+          begin
+            Result := true;
+            exit;
+          end;
+          inc( Addr1 );
+          inc( Addr2 );
+        end;
+        inc( Addr1, Mod1 );
+        inc( Addr2, Mod2 );
+      end;
+    2 :
+      for ty := 1 to ScanHeight do
+      begin
+        for tx := 1 to ScanWidth do
+        begin
+          if ( PWord( Addr1 )^ <> TransparentColor1 ) and ( PWord( Addr2 )^ <>
+            TransparentColor2 ) then
+          begin
+            Result := true;
+            exit;
+          end;
+          inc( Addr1, 2 );
+          inc( Addr2, 2 );
+        end;
+        inc( Addr1, Mod1 );
+        inc( Addr2, Mod2 );
+      end;
+    3 :
+      for ty := 1 to ScanHeight do
+      begin
+        for tx := 1 to ScanWidth do
+        begin
+          Color1 := PLongWord( Addr1 )^ and $00FFFFFF;
+          Color2 := PLongWord( Addr2 )^ and $00FFFFFF;
+          if ( Color1 <> TransparentColor1 ) and ( Color2 <> TransparentColor2 )
+            then
+          begin
+            Result := true;
+            exit;
+          end;
+          inc( Addr1, 3 );
+          inc( Addr2, 3 );
+        end;
+        inc( Addr1, Mod1 );
+        inc( Addr2, Mod2 );
+      end;
+    4 :
+      for ty := 1 to ScanHeight do
+      begin
+        for tx := 1 to ScanWidth do
+        begin
+          if ( PLongWord( Addr1 )^ <> TransparentColor1 ) and ( PLongWord( Addr2 )^ <>
+            TransparentColor2 ) then
+          begin
+            Result := true;
+            exit;
+          end;
+          inc( Addr1, 4 );
+          inc( Addr2, 4 );
+        end;
+        inc( Addr1, Mod1 );
+        inc( Addr2, Mod2 );
+      end;
+  end;
+end;
+
+procedure SDL_AddPixel( DstSurface : PSDL_Surface; x : cardinal; y : cardinal; Color :
+  cardinal );
+var
+  SrcColor     : cardinal;
+  Addr         : cardinal;
+  R, G, B      : cardinal;
+begin
+  if Color = 0 then
+    exit;
+  with DstSurface^ do
+  begin
+    Addr := cardinal( Pixels ) + y * Pitch + x * format.BytesPerPixel;
+    SrcColor := PUInt32( Addr )^;
+    case format.BitsPerPixel of
+      8 :
+        begin
+          R := SrcColor and $E0 + Color and $E0;
+          G := SrcColor and $1C + Color and $1C;
+          B := SrcColor and $03 + Color and $03;
+          if R > $E0 then
+            R := $E0;
+          if G > $1C then
+            G := $1C;
+          if B > $03 then
+            B := $03;
+          PUInt8( Addr )^ := R or G or B;
+        end;
+      15 :
+        begin
+          R := SrcColor and $7C00 + Color and $7C00;
+          G := SrcColor and $03E0 + Color and $03E0;
+          B := SrcColor and $001F + Color and $001F;
+          if R > $7C00 then
+            R := $7C00;
+          if G > $03E0 then
+            G := $03E0;
+          if B > $001F then
+            B := $001F;
+          PUInt16( Addr )^ := R or G or B;
+        end;
+      16 :
+        begin
+          R := SrcColor and $F800 + Color and $F800;
+          G := SrcColor and $07C0 + Color and $07C0;
+          B := SrcColor and $001F + Color and $001F;
+          if R > $F800 then
+            R := $F800;
+          if G > $07C0 then
+            G := $07C0;
+          if B > $001F then
+            B := $001F;
+          PUInt16( Addr )^ := R or G or B;
+        end;
+      24 :
+        begin
+          R := SrcColor and $00FF0000 + Color and $00FF0000;
+          G := SrcColor and $0000FF00 + Color and $0000FF00;
+          B := SrcColor and $000000FF + Color and $000000FF;
+          if R > $FF0000 then
+            R := $FF0000;
+          if G > $00FF00 then
+            G := $00FF00;
+          if B > $0000FF then
+            B := $0000FF;
+          PUInt32( Addr )^ := SrcColor and $FF000000 or R or G or B;
+        end;
+      32 :
+        begin
+          R := SrcColor and $00FF0000 + Color and $00FF0000;
+          G := SrcColor and $0000FF00 + Color and $0000FF00;
+          B := SrcColor and $000000FF + Color and $000000FF;
+          if R > $FF0000 then
+            R := $FF0000;
+          if G > $00FF00 then
+            G := $00FF00;
+          if B > $0000FF then
+            B := $0000FF;
+          PUInt32( Addr )^ := R or G or B;
+        end;
+    end;
+  end;
+end;
+
+procedure SDL_SubPixel( DstSurface : PSDL_Surface; x : cardinal; y : cardinal; Color :
+  cardinal );
+var
+  SrcColor     : cardinal;
+  Addr         : cardinal;
+  R, G, B      : cardinal;
+begin
+  if Color = 0 then
+    exit;
+  with DstSurface^ do
+  begin
+    Addr := cardinal( Pixels ) + y * Pitch + x * format.BytesPerPixel;
+    SrcColor := PUInt32( Addr )^;
+    case format.BitsPerPixel of
+      8 :
+        begin
+          R := SrcColor and $E0 - Color and $E0;
+          G := SrcColor and $1C - Color and $1C;
+          B := SrcColor and $03 - Color and $03;
+          if R > $E0 then
+            R := 0;
+          if G > $1C then
+            G := 0;
+          if B > $03 then
+            B := 0;
+          PUInt8( Addr )^ := R or G or B;
+        end;
+      15 :
+        begin
+          R := SrcColor and $7C00 - Color and $7C00;
+          G := SrcColor and $03E0 - Color and $03E0;
+          B := SrcColor and $001F - Color and $001F;
+          if R > $7C00 then
+            R := 0;
+          if G > $03E0 then
+            G := 0;
+          if B > $001F then
+            B := 0;
+          PUInt16( Addr )^ := R or G or B;
+        end;
+      16 :
+        begin
+          R := SrcColor and $F800 - Color and $F800;
+          G := SrcColor and $07C0 - Color and $07C0;
+          B := SrcColor and $001F - Color and $001F;
+          if R > $F800 then
+            R := 0;
+          if G > $07C0 then
+            G := 0;
+          if B > $001F then
+            B := 0;
+          PUInt16( Addr )^ := R or G or B;
+        end;
+      24 :
+        begin
+          R := SrcColor and $00FF0000 - Color and $00FF0000;
+          G := SrcColor and $0000FF00 - Color and $0000FF00;
+          B := SrcColor and $000000FF - Color and $000000FF;
+          if R > $FF0000 then
+            R := 0;
+          if G > $00FF00 then
+            G := 0;
+          if B > $0000FF then
+            B := 0;
+          PUInt32( Addr )^ := SrcColor and $FF000000 or R or G or B;
+        end;
+      32 :
+        begin
+          R := SrcColor and $00FF0000 - Color and $00FF0000;
+          G := SrcColor and $0000FF00 - Color and $0000FF00;
+          B := SrcColor and $000000FF - Color and $000000FF;
+          if R > $FF0000 then
+            R := 0;
+          if G > $00FF00 then
+            G := 0;
+          if B > $0000FF then
+            B := 0;
+          PUInt32( Addr )^ := R or G or B;
+        end;
+    end;
+  end;
+end;
+// This procedure works on 8, 15, 16, 24 and 32 bits color depth surfaces.
+// In 8 bit color depth mode the procedure works with the default packed
+//  palette (RRRGGGBB). It handles all clipping.
+
+procedure SDL_AddSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;
+  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );
+var
+  R, G, B, Pixel1, Pixel2, TransparentColor : cardinal;
+  Src, Dest    : TSDL_Rect;
+  Diff         : integer;
+  SrcAddr, DestAddr : cardinal;
+  WorkX, WorkY : word;
+  SrcMod, DestMod : cardinal;
+  Bits         : cardinal;
+begin
+  if ( SrcSurface = nil ) or ( DestSurface = nil ) then
+    exit; // Remove this to make it faster
+  if ( SrcSurface.Format.BitsPerPixel <> DestSurface.Format.BitsPerPixel ) then
+    exit; // Remove this to make it faster
+  if SrcRect = nil then
+  begin
+    with Src do
+    begin
+      x := 0;
+      y := 0;
+      w := SrcSurface.w;
+      h := SrcSurface.h;
+    end;
+  end
+  else
+    Src := SrcRect^;
+  if DestRect = nil then
+  begin
+    Dest.x := 0;
+    Dest.y := 0;
+  end
+  else
+    Dest := DestRect^;
+  Dest.w := Src.w;
+  Dest.h := Src.h;
+  with DestSurface.Clip_Rect do
+  begin
+    // Source's right side is greater than the dest.cliprect
+    if Dest.x + Src.w > x + w then
+    begin
+      smallint( Src.w ) := x + w - Dest.x;
+      smallint( Dest.w ) := x + w - Dest.x;
+      if smallint( Dest.w ) < 1 then
+        exit;
+    end;
+    // Source's bottom side is greater than the dest.clip
+    if Dest.y + Src.h > y + h then
+    begin
+      smallint( Src.h ) := y + h - Dest.y;
+      smallint( Dest.h ) := y + h - Dest.y;
+      if smallint( Dest.h ) < 1 then
+        exit;
+    end;
+    // Source's left side is less than the dest.clip
+    if Dest.x < x then
+    begin
+      Diff := x - Dest.x;
+      Src.x := Src.x + Diff;
+      smallint( Src.w ) := smallint( Src.w ) - Diff;
+      Dest.x := x;
+      smallint( Dest.w ) := smallint( Dest.w ) - Diff;
+      if smallint( Dest.w ) < 1 then
+        exit;
+    end;
+    // Source's Top side is less than the dest.clip
+    if Dest.y < y then
+    begin
+      Diff := y - Dest.y;
+      Src.y := Src.y + Diff;
+      smallint( Src.h ) := smallint( Src.h ) - Diff;
+      Dest.y := y;
+      smallint( Dest.h ) := smallint( Dest.h ) - Diff;
+      if smallint( Dest.h ) < 1 then
+        exit;
+    end;
+  end;
+  with SrcSurface^ do
+  begin
+    SrcAddr := cardinal( Pixels ) + UInt32( Src.y ) * Pitch + UInt32( Src.x ) *
+      Format.BytesPerPixel;
+    SrcMod := Pitch - Src.w * Format.BytesPerPixel;
+    TransparentColor := Format.colorkey;
+  end;
+  with DestSurface^ do
+  begin
+    DestAddr := cardinal( Pixels ) + UInt32( Dest.y ) * Pitch + UInt32( Dest.x ) *
+      Format.BytesPerPixel;
+    DestMod := Pitch - Dest.w * Format.BytesPerPixel;
+    Bits := Format.BitsPerPixel;
+  end;
+  SDL_LockSurface( SrcSurface );
+  SDL_LockSurface( DestSurface );
+  WorkY := Src.h;
+  case bits of
+    8 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt8( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt8( DestAddr )^;
+              if Pixel2 > 0 then
+              begin
+                R := Pixel1 and $E0 + Pixel2 and $E0;
+                G := Pixel1 and $1C + Pixel2 and $1C;
+                B := Pixel1 and $03 + Pixel2 and $03;
+                if R > $E0 then
+                  R := $E0;
+                if G > $1C then
+                  G := $1C;
+                if B > $03 then
+                  B := $03;
+                PUInt8( DestAddr )^ := R or G or B;
+              end
+              else
+                PUInt8( DestAddr )^ := Pixel1;
+            end;
+            inc( SrcAddr );
+            inc( DestAddr );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    15 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt16( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt16( DestAddr )^;
+              if Pixel2 > 0 then
+              begin
+                R := Pixel1 and $7C00 + Pixel2 and $7C00;
+                G := Pixel1 and $03E0 + Pixel2 and $03E0;
+                B := Pixel1 and $001F + Pixel2 and $001F;
+                if R > $7C00 then
+                  R := $7C00;
+                if G > $03E0 then
+                  G := $03E0;
+                if B > $001F then
+                  B := $001F;
+                PUInt16( DestAddr )^ := R or G or B;
+              end
+              else
+                PUInt16( DestAddr )^ := Pixel1;
+            end;
+            inc( SrcAddr, 2 );
+            inc( DestAddr, 2 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    16 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt16( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt16( DestAddr )^;
+              if Pixel2 > 0 then
+              begin
+                R := Pixel1 and $F800 + Pixel2 and $F800;
+                G := Pixel1 and $07E0 + Pixel2 and $07E0;
+                B := Pixel1 and $001F + Pixel2 and $001F;
+                if R > $F800 then
+                  R := $F800;
+                if G > $07E0 then
+                  G := $07E0;
+                if B > $001F then
+                  B := $001F;
+                PUInt16( DestAddr )^ := R or G or B;
+              end
+              else
+                PUInt16( DestAddr )^ := Pixel1;
+            end;
+            inc( SrcAddr, 2 );
+            inc( DestAddr, 2 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    24 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt32( SrcAddr )^ and $00FFFFFF;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt32( DestAddr )^ and $00FFFFFF;
+              if Pixel2 > 0 then
+              begin
+                R := Pixel1 and $FF0000 + Pixel2 and $FF0000;
+                G := Pixel1 and $00FF00 + Pixel2 and $00FF00;
+                B := Pixel1 and $0000FF + Pixel2 and $0000FF;
+                if R > $FF0000 then
+                  R := $FF0000;
+                if G > $00FF00 then
+                  G := $00FF00;
+                if B > $0000FF then
+                  B := $0000FF;
+                PUInt32( DestAddr )^ := PUInt32( DestAddr )^ and $FF000000 or ( R or G or B );
+              end
+              else
+                PUInt32( DestAddr )^ := PUInt32( DestAddr )^ and $FF000000 or Pixel1;
+            end;
+            inc( SrcAddr, 3 );
+            inc( DestAddr, 3 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    32 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt32( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt32( DestAddr )^;
+              if Pixel2 > 0 then
+              begin
+                R := Pixel1 and $FF0000 + Pixel2 and $FF0000;
+                G := Pixel1 and $00FF00 + Pixel2 and $00FF00;
+                B := Pixel1 and $0000FF + Pixel2 and $0000FF;
+                if R > $FF0000 then
+                  R := $FF0000;
+                if G > $00FF00 then
+                  G := $00FF00;
+                if B > $0000FF then
+                  B := $0000FF;
+                PUInt32( DestAddr )^ := R or G or B;
+              end
+              else
+                PUInt32( DestAddr )^ := Pixel1;
+            end;
+            inc( SrcAddr, 4 );
+            inc( DestAddr, 4 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+  end;
+  SDL_UnlockSurface( SrcSurface );
+  SDL_UnlockSurface( DestSurface );
+end;
+
+procedure SDL_SubSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;
+  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );
+var
+  R, G, B, Pixel1, Pixel2, TransparentColor : cardinal;
+  Src, Dest    : TSDL_Rect;
+  Diff         : integer;
+  SrcAddr, DestAddr : cardinal;
+//{*_ebx, *}{*_esi, *}{*_edi, _esp*} : cardinal; // Auto Removed, Unused Variable (_ebx) // Auto Removed, Unused Variable (_esi) // Auto Removed, Unused Variable (_edi)
+  WorkX, WorkY : word;
+  SrcMod, DestMod : cardinal;
+  Bits         : cardinal;
+begin
+  if ( SrcSurface = nil ) or ( DestSurface = nil ) then
+    exit; // Remove this to make it faster
+  if ( SrcSurface.Format.BitsPerPixel <> DestSurface.Format.BitsPerPixel ) then
+    exit; // Remove this to make it faster
+  if SrcRect = nil then
+  begin
+    with Src do
+    begin
+      x := 0;
+      y := 0;
+      w := SrcSurface.w;
+      h := SrcSurface.h;
+    end;
+  end
+  else
+    Src := SrcRect^;
+  if DestRect = nil then
+  begin
+    Dest.x := 0;
+    Dest.y := 0;
+  end
+  else
+    Dest := DestRect^;
+  Dest.w := Src.w;
+  Dest.h := Src.h;
+  with DestSurface.Clip_Rect do
+  begin
+    // Source's right side is greater than the dest.cliprect
+    if Dest.x + Src.w > x + w then
+    begin
+      smallint( Src.w ) := x + w - Dest.x;
+      smallint( Dest.w ) := x + w - Dest.x;
+      if smallint( Dest.w ) < 1 then
+        exit;
+    end;
+    // Source's bottom side is greater than the dest.clip
+    if Dest.y + Src.h > y + h then
+    begin
+      smallint( Src.h ) := y + h - Dest.y;
+      smallint( Dest.h ) := y + h - Dest.y;
+      if smallint( Dest.h ) < 1 then
+        exit;
+    end;
+    // Source's left side is less than the dest.clip
+    if Dest.x < x then
+    begin
+      Diff := x - Dest.x;
+      Src.x := Src.x + Diff;
+      smallint( Src.w ) := smallint( Src.w ) - Diff;
+      Dest.x := x;
+      smallint( Dest.w ) := smallint( Dest.w ) - Diff;
+      if smallint( Dest.w ) < 1 then
+        exit;
+    end;
+    // Source's Top side is less than the dest.clip
+    if Dest.y < y then
+    begin
+      Diff := y - Dest.y;
+      Src.y := Src.y + Diff;
+      smallint( Src.h ) := smallint( Src.h ) - Diff;
+      Dest.y := y;
+      smallint( Dest.h ) := smallint( Dest.h ) - Diff;
+      if smallint( Dest.h ) < 1 then
+        exit;
+    end;
+  end;
+  with SrcSurface^ do
+  begin
+    SrcAddr := cardinal( Pixels ) + UInt32( Src.y ) * Pitch + UInt32( Src.x ) *
+      Format.BytesPerPixel;
+    SrcMod := Pitch - Src.w * Format.BytesPerPixel;
+    TransparentColor := Format.colorkey;
+  end;
+  with DestSurface^ do
+  begin
+    DestAddr := cardinal( Pixels ) + UInt32( Dest.y ) * Pitch + UInt32( Dest.x ) *
+      Format.BytesPerPixel;
+    DestMod := Pitch - Dest.w * Format.BytesPerPixel;
+    Bits := DestSurface.Format.BitsPerPixel;
+  end;
+  SDL_LockSurface( SrcSurface );
+  SDL_LockSurface( DestSurface );
+  WorkY := Src.h;
+  case bits of
+    8 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt8( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt8( DestAddr )^;
+              if Pixel2 > 0 then
+              begin
+                R := Pixel2 and $E0 - Pixel1 and $E0;
+                G := Pixel2 and $1C - Pixel1 and $1C;
+                B := Pixel2 and $03 - Pixel1 and $03;
+                if R > $E0 then
+                  R := 0;
+                if G > $1C then
+                  G := 0;
+                if B > $03 then
+                  B := 0;
+                PUInt8( DestAddr )^ := R or G or B;
+              end;
+            end;
+            inc( SrcAddr );
+            inc( DestAddr );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    15 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt16( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt16( DestAddr )^;
+              if Pixel2 > 0 then
+              begin
+                R := Pixel2 and $7C00 - Pixel1 and $7C00;
+                G := Pixel2 and $03E0 - Pixel1 and $03E0;
+                B := Pixel2 and $001F - Pixel1 and $001F;
+                if R > $7C00 then
+                  R := 0;
+                if G > $03E0 then
+                  G := 0;
+                if B > $001F then
+                  B := 0;
+                PUInt16( DestAddr )^ := R or G or B;
+              end;
+            end;
+            inc( SrcAddr, 2 );
+            inc( DestAddr, 2 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    16 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt16( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt16( DestAddr )^;
+              if Pixel2 > 0 then
+              begin
+                R := Pixel2 and $F800 - Pixel1 and $F800;
+                G := Pixel2 and $07E0 - Pixel1 and $07E0;
+                B := Pixel2 and $001F - Pixel1 and $001F;
+                if R > $F800 then
+                  R := 0;
+                if G > $07E0 then
+                  G := 0;
+                if B > $001F then
+                  B := 0;
+                PUInt16( DestAddr )^ := R or G or B;
+              end;
+            end;
+            inc( SrcAddr, 2 );
+            inc( DestAddr, 2 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    24 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt32( SrcAddr )^ and $00FFFFFF;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt32( DestAddr )^ and $00FFFFFF;
+              if Pixel2 > 0 then
+              begin
+                R := Pixel2 and $FF0000 - Pixel1 and $FF0000;
+                G := Pixel2 and $00FF00 - Pixel1 and $00FF00;
+                B := Pixel2 and $0000FF - Pixel1 and $0000FF;
+                if R > $FF0000 then
+                  R := 0;
+                if G > $00FF00 then
+                  G := 0;
+                if B > $0000FF then
+                  B := 0;
+                PUInt32( DestAddr )^ := PUInt32( DestAddr )^ and $FF000000 or ( R or G or B );
+              end;
+            end;
+            inc( SrcAddr, 3 );
+            inc( DestAddr, 3 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    32 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt32( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt32( DestAddr )^;
+              if Pixel2 > 0 then
+              begin
+                R := Pixel2 and $FF0000 - Pixel1 and $FF0000;
+                G := Pixel2 and $00FF00 - Pixel1 and $00FF00;
+                B := Pixel2 and $0000FF - Pixel1 and $0000FF;
+                if R > $FF0000 then
+                  R := 0;
+                if G > $00FF00 then
+                  G := 0;
+                if B > $0000FF then
+                  B := 0;
+                PUInt32( DestAddr )^ := R or G or B;
+              end
+              else
+                PUInt32( DestAddr )^ := Pixel2;
+            end;
+            inc( SrcAddr, 4 );
+            inc( DestAddr, 4 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+  end;
+  SDL_UnlockSurface( SrcSurface );
+  SDL_UnlockSurface( DestSurface );
+end;
+
+procedure SDL_MonoSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;
+  DestSurface : PSDL_Surface; DestRect : PSDL_Rect; Color : cardinal );
+var
+  Src, Dest    : TSDL_Rect;
+  Diff         : integer;
+  SrcAddr, DestAddr : cardinal;
+//{*_ebx, *}{*_esi, *}{*_edi, _esp*} : cardinal; // Auto Removed, Unused Variable (_ebx) // Auto Removed, Unused Variable (_esi) // Auto Removed, Unused Variable (_edi)
+  WorkX, WorkY : word;
+  SrcMod, DestMod : cardinal;
+  TransparentColor, SrcColor : cardinal;
+  BPP          : cardinal;
+begin
+  if ( SrcSurface = nil ) or ( DestSurface = nil ) then
+    exit; // Remove this to make it faster
+  if ( SrcSurface.Format.BitsPerPixel <> DestSurface.Format.BitsPerPixel ) then
+    exit; // Remove this to make it faster
+  if SrcRect = nil then
+  begin
+    with Src do
+    begin
+      x := 0;
+      y := 0;
+      w := SrcSurface.w;
+      h := SrcSurface.h;
+    end;
+  end
+  else
+    Src := SrcRect^;
+  if DestRect = nil then
+  begin
+    Dest.x := 0;
+    Dest.y := 0;
+  end
+  else
+    Dest := DestRect^;
+  Dest.w := Src.w;
+  Dest.h := Src.h;
+  with DestSurface.Clip_Rect do
+  begin
+    // Source's right side is greater than the dest.cliprect
+    if Dest.x + Src.w > x + w then
+    begin
+      smallint( Src.w ) := x + w - Dest.x;
+      smallint( Dest.w ) := x + w - Dest.x;
+      if smallint( Dest.w ) < 1 then
+        exit;
+    end;
+    // Source's bottom side is greater than the dest.clip
+    if Dest.y + Src.h > y + h then
+    begin
+      smallint( Src.h ) := y + h - Dest.y;
+      smallint( Dest.h ) := y + h - Dest.y;
+      if smallint( Dest.h ) < 1 then
+        exit;
+    end;
+    // Source's left side is less than the dest.clip
+    if Dest.x < x then
+    begin
+      Diff := x - Dest.x;
+      Src.x := Src.x + Diff;
+      smallint( Src.w ) := smallint( Src.w ) - Diff;
+      Dest.x := x;
+      smallint( Dest.w ) := smallint( Dest.w ) - Diff;
+      if smallint( Dest.w ) < 1 then
+        exit;
+    end;
+    // Source's Top side is less than the dest.clip
+    if Dest.y < y then
+    begin
+      Diff := y - Dest.y;
+      Src.y := Src.y + Diff;
+      smallint( Src.h ) := smallint( Src.h ) - Diff;
+      Dest.y := y;
+      smallint( Dest.h ) := smallint( Dest.h ) - Diff;
+      if smallint( Dest.h ) < 1 then
+        exit;
+    end;
+  end;
+  with SrcSurface^ do
+  begin
+    SrcAddr := cardinal( Pixels ) + UInt32( Src.y ) * Pitch + UInt32( Src.x ) *
+      Format.BytesPerPixel;
+    SrcMod := Pitch - Src.w * Format.BytesPerPixel;
+    TransparentColor := Format.colorkey;
+  end;
+  with DestSurface^ do
+  begin
+    DestAddr := cardinal( Pixels ) + UInt32( Dest.y ) * Pitch + UInt32( Dest.x ) *
+      Format.BytesPerPixel;
+    DestMod := Pitch - Dest.w * Format.BytesPerPixel;
+    BPP := DestSurface.Format.BytesPerPixel;
+  end;
+  SDL_LockSurface( SrcSurface );
+  SDL_LockSurface( DestSurface );
+  WorkY := Src.h;
+  case BPP of
+    1 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            SrcColor := PUInt8( SrcAddr )^;
+            if SrcColor <> TransparentColor then
+              PUInt8( DestAddr )^ := SrcColor;
+            inc( SrcAddr );
+            inc( DestAddr );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    2 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            SrcColor := PUInt16( SrcAddr )^;
+            if SrcColor <> TransparentColor then
+              PUInt16( DestAddr )^ := SrcColor;
+            inc( SrcAddr );
+            inc( DestAddr );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    3 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            SrcColor := PUInt32( SrcAddr )^ and $FFFFFF;
+            if SrcColor <> TransparentColor then
+              PUInt32( DestAddr )^ := ( PUInt32( DestAddr )^ and $FFFFFF ) or SrcColor;
+            inc( SrcAddr );
+            inc( DestAddr );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    4 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            SrcColor := PUInt32( SrcAddr )^;
+            if SrcColor <> TransparentColor then
+              PUInt32( DestAddr )^ := SrcColor;
+            inc( SrcAddr );
+            inc( DestAddr );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+  end;
+  SDL_UnlockSurface( SrcSurface );
+  SDL_UnlockSurface( DestSurface );
+end;
+// TextureRect.w and TextureRect.h are not used.
+// The TextureSurface's size MUST larger than the drawing rectangle!!!
+
+procedure SDL_TexturedSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;
+  DestSurface : PSDL_Surface; DestRect : PSDL_Rect; Texture : PSDL_Surface;
+  TextureRect : PSDL_Rect );
+var
+  Src, Dest    : TSDL_Rect;
+  Diff         : integer;
+  SrcAddr, DestAddr, TextAddr : cardinal;
+//{*_ebx, *}{*_esi, *}{*_edi, _esp*}: cardinal; // Auto Removed, Unused Variable (_ebx) // Auto Removed, Unused Variable (_esi) // Auto Removed, Unused Variable (_edi)
+  WorkX, WorkY : word;
+  SrcMod, DestMod, TextMod : cardinal;
+SrcColor, TransparentColor{*, TextureColor*} : cardinal; // Auto Removed, Unused Variable (TextureColor)
+  BPP          : cardinal;
+begin
+  if ( SrcSurface = nil ) or ( DestSurface = nil ) then
+    exit; // Remove this to make it faster
+  if ( SrcSurface.Format.BitsPerPixel <> DestSurface.Format.BitsPerPixel ) then
+    exit; // Remove this to make it faster
+  if SrcRect = nil then
+  begin
+    with Src do
+    begin
+      x := 0;
+      y := 0;
+      w := SrcSurface.w;
+      h := SrcSurface.h;
+    end;
+  end
+  else
+    Src := SrcRect^;
+  if DestRect = nil then
+  begin
+    Dest.x := 0;
+    Dest.y := 0;
+  end
+  else
+    Dest := DestRect^;
+  Dest.w := Src.w;
+  Dest.h := Src.h;
+  with DestSurface.Clip_Rect do
+  begin
+    // Source's right side is greater than the dest.cliprect
+    if Dest.x + Src.w > x + w then
+    begin
+      smallint( Src.w ) := x + w - Dest.x;
+      smallint( Dest.w ) := x + w - Dest.x;
+      if smallint( Dest.w ) < 1 then
+        exit;
+    end;
+    // Source's bottom side is greater than the dest.clip
+    if Dest.y + Src.h > y + h then
+    begin
+      smallint( Src.h ) := y + h - Dest.y;
+      smallint( Dest.h ) := y + h - Dest.y;
+      if smallint( Dest.h ) < 1 then
+        exit;
+    end;
+    // Source's left side is less than the dest.clip
+    if Dest.x < x then
+    begin
+      Diff := x - Dest.x;
+      Src.x := Src.x + Diff;
+      smallint( Src.w ) := smallint( Src.w ) - Diff;
+      Dest.x := x;
+      smallint( Dest.w ) := smallint( Dest.w ) - Diff;
+      if smallint( Dest.w ) < 1 then
+        exit;
+    end;
+    // Source's Top side is less than the dest.clip
+    if Dest.y < y then
+    begin
+      Diff := y - Dest.y;
+      Src.y := Src.y + Diff;
+      smallint( Src.h ) := smallint( Src.h ) - Diff;
+      Dest.y := y;
+      smallint( Dest.h ) := smallint( Dest.h ) - Diff;
+      if smallint( Dest.h ) < 1 then
+        exit;
+    end;
+  end;
+  with SrcSurface^ do
+  begin
+    SrcAddr := cardinal( Pixels ) + UInt32( Src.y ) * Pitch + UInt32( Src.x ) *
+      Format.BytesPerPixel;
+    SrcMod := Pitch - Src.w * Format.BytesPerPixel;
+    TransparentColor := format.colorkey;
+  end;
+  with DestSurface^ do
+  begin
+    DestAddr := cardinal( Pixels ) + UInt32( Dest.y ) * Pitch + UInt32( Dest.x ) *
+      Format.BytesPerPixel;
+    DestMod := Pitch - Dest.w * Format.BytesPerPixel;
+    BPP := DestSurface.Format.BitsPerPixel;
+  end;
+  with Texture^ do
+  begin
+    TextAddr := cardinal( Pixels ) + UInt32( TextureRect.y ) * Pitch +
+      UInt32( TextureRect.x ) * Format.BytesPerPixel;
+    TextMod := Pitch - Src.w * Format.BytesPerPixel;
+  end;
+  SDL_LockSurface( SrcSurface );
+  SDL_LockSurface( DestSurface );
+  SDL_LockSurface( Texture );
+  WorkY := Src.h;
+  case BPP of
+    1 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            SrcColor := PUInt8( SrcAddr )^;
+            if SrcColor <> TransparentColor then
+              PUInt8( DestAddr )^ := PUint8( TextAddr )^;
+            inc( SrcAddr );
+            inc( DestAddr );
+            inc( TextAddr );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          inc( TextAddr, TextMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    2 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            SrcColor := PUInt16( SrcAddr )^;
+            if SrcColor <> TransparentColor then
+              PUInt16( DestAddr )^ := PUInt16( TextAddr )^;
+            inc( SrcAddr );
+            inc( DestAddr );
+            inc( TextAddr );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          inc( TextAddr, TextMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    3 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            SrcColor := PUInt32( SrcAddr )^ and $FFFFFF;
+            if SrcColor <> TransparentColor then
+              PUInt32( DestAddr )^ := ( PUInt32( DestAddr )^ and $FFFFFF ) or ( PUInt32( TextAddr )^ and $FFFFFF );
+            inc( SrcAddr );
+            inc( DestAddr );
+            inc( TextAddr );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          inc( TextAddr, TextMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    4 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            SrcColor := PUInt32( SrcAddr )^;
+            if SrcColor <> TransparentColor then
+              PUInt32( DestAddr )^ := PUInt32( TextAddr )^;
+            inc( SrcAddr );
+            inc( DestAddr );
+            inc( TextAddr );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          inc( TextAddr, TextMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+  end;
+  SDL_UnlockSurface( SrcSurface );
+  SDL_UnlockSurface( DestSurface );
+  SDL_UnlockSurface( Texture );
+end;
+
+procedure SDL_ZoomSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect; DstSurface : PSDL_Surface; DstRect : PSDL_Rect );
+var
+  xc, yc       : cardinal;
+  rx, wx, ry, wy, ry16 : cardinal;
+  color        : cardinal;
+  modx, mody   : cardinal;
+begin
+  // Warning! No checks for surface pointers!!!
+  if srcrect = nil then
+    srcrect := @SrcSurface.clip_rect;
+  if dstrect = nil then
+    dstrect := @DstSurface.clip_rect;
+  if SDL_MustLock( SrcSurface ) then
+    SDL_LockSurface( SrcSurface );
+  if SDL_MustLock( DstSurface ) then
+    SDL_LockSurface( DstSurface );
+  modx := trunc( ( srcrect.w / dstrect.w ) * 65536 );
+  mody := trunc( ( srcrect.h / dstrect.h ) * 65536 );
+  //rx := srcrect.x * 65536;
+  ry := srcrect.y * 65536;
+  wy := dstrect.y;
+  for yc := 0 to dstrect.h - 1 do
+  begin
+    rx := srcrect.x * 65536;
+    wx := dstrect.x;
+    ry16 := ry shr 16;
+    for xc := 0 to dstrect.w - 1 do
+    begin
+      color := SDL_GetPixel( SrcSurface, rx shr 16, ry16 );
+      SDL_PutPixel( DstSurface, wx, wy, color );
+      rx := rx + modx;
+      inc( wx );
+    end;
+    ry := ry + mody;
+    inc( wy );
+  end;
+  if SDL_MustLock( SrcSurface ) then
+    SDL_UnlockSurface( SrcSurface );
+  if SDL_MustLock( DstSurface ) then
+    SDL_UnlockSurface( DstSurface );
+end;
+// Re-map a rectangular area into an area defined by four vertices
+// Converted from C to Pascal by KiCHY
+
+procedure SDL_WarpSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect; DstSurface : PSDL_Surface; UL, UR, LR, LL : PPoint );
+const
+  SHIFTS       = 15; // Extend ints to limit round-off error (try 2 - 20)
+  THRESH       = 1 shl SHIFTS; // Threshold for pixel size value
+  procedure CopySourceToDest( UL, UR, LR, LL : TPoint; x1, y1, x2, y2 : cardinal );
+  var
+    tm, lm, rm, bm, m : TPoint;
+    mx, my     : cardinal;
+    cr         : cardinal;
+  begin
+    // Does the destination area specify a single pixel?
+    if ( ( abs( ul.x - ur.x ) < THRESH ) and
+      ( abs( ul.x - lr.x ) < THRESH ) and
+      ( abs( ul.x - ll.x ) < THRESH ) and
+      ( abs( ul.y - ur.y ) < THRESH ) and
+      ( abs( ul.y - lr.y ) < THRESH ) and
+      ( abs( ul.y - ll.y ) < THRESH ) ) then
+    begin // Yes
+      cr := SDL_GetPixel( SrcSurface, ( x1 shr SHIFTS ), ( y1 shr SHIFTS ) );
+      SDL_PutPixel( DstSurface, ( ul.x shr SHIFTS ), ( ul.y shr SHIFTS ), cr );
+    end
+    else
+    begin // No
+      // Quarter the source and the destination, and then recurse
+      tm.x := ( ul.x + ur.x ) shr 1;
+      tm.y := ( ul.y + ur.y ) shr 1;
+      bm.x := ( ll.x + lr.x ) shr 1;
+      bm.y := ( ll.y + lr.y ) shr 1;
+      lm.x := ( ul.x + ll.x ) shr 1;
+      lm.y := ( ul.y + ll.y ) shr 1;
+      rm.x := ( ur.x + lr.x ) shr 1;
+      rm.y := ( ur.y + lr.y ) shr 1;
+      m.x := ( tm.x + bm.x ) shr 1;
+      m.y := ( tm.y + bm.y ) shr 1;
+      mx := ( x1 + x2 ) shr 1;
+      my := ( y1 + y2 ) shr 1;
+      CopySourceToDest( ul, tm, m, lm, x1, y1, mx, my );
+      CopySourceToDest( tm, ur, rm, m, mx, y1, x2, my );
+      CopySourceToDest( m, rm, lr, bm, mx, my, x2, y2 );
+      CopySourceToDest( lm, m, bm, ll, x1, my, mx, y2 );
+    end;
+  end;
+var
+  _UL, _UR, _LR, _LL : TPoint;
+  Rect_x, Rect_y, Rect_w, Rect_h : integer;
+begin
+  if SDL_MustLock( SrcSurface ) then
+    SDL_LockSurface( SrcSurface );
+  if SDL_MustLock( DstSurface ) then
+    SDL_LockSurface( DstSurface );
+  if SrcRect = nil then
+  begin
+    Rect_x := 0;
+    Rect_y := 0;
+    Rect_w := ( SrcSurface.w - 1 ) shl SHIFTS;
+    Rect_h := ( SrcSurface.h - 1 ) shl SHIFTS;
+  end
+  else
+  begin
+    Rect_x := SrcRect.x;
+    Rect_y := SrcRect.y;
+    Rect_w := ( SrcRect.w - 1 ) shl SHIFTS;
+    Rect_h := ( SrcRect.h - 1 ) shl SHIFTS;
+  end;
+  // Shift all values to help reduce round-off error.
+  _ul.x := ul.x shl SHIFTS;
+  _ul.y := ul.y shl SHIFTS;
+  _ur.x := ur.x shl SHIFTS;
+  _ur.y := ur.y shl SHIFTS;
+  _lr.x := lr.x shl SHIFTS;
+  _lr.y := lr.y shl SHIFTS;
+  _ll.x := ll.x shl SHIFTS;
+  _ll.y := ll.y shl SHIFTS;
+  CopySourceToDest( _ul, _ur, _lr, _ll, Rect_x, Rect_y, Rect_w, Rect_h );
+  if SDL_MustLock( SrcSurface ) then
+    SDL_UnlockSurface( SrcSurface );
+  if SDL_MustLock( DstSurface ) then
+    SDL_UnlockSurface( DstSurface );
+end;
+
+// Draw a line between x1,y1 and x2,y2 to the given surface
+// NOTE: The surface must be locked before calling this!
+
+procedure SDL_DrawLine( DstSurface : PSDL_Surface; x1, y1, x2, y2 : integer; Color :
+  cardinal );
+var
+  dx, dy, sdx, sdy, x, y, px, py : integer;
+begin
+  dx := x2 - x1;
+  dy := y2 - y1;
+  if dx < 0 then
+    sdx := -1
+  else
+    sdx := 1;
+  if dy < 0 then
+    sdy := -1
+  else
+    sdy := 1;
+  dx := sdx * dx + 1;
+  dy := sdy * dy + 1;
+  x := 0;
+  y := 0;
+  px := x1;
+  py := y1;
+  if dx >= dy then
+  begin
+    for x := 0 to dx - 1 do
+    begin
+      SDL_PutPixel( DstSurface, px, py, Color );
+      y := y + dy;
+      if y >= dx then
+      begin
+        y := y - dx;
+        py := py + sdy;
+      end;
+      px := px + sdx;
+    end;
+  end
+  else
+  begin
+    for y := 0 to dy - 1 do
+    begin
+      SDL_PutPixel( DstSurface, px, py, Color );
+      x := x + dx;
+      if x >= dy then
+      begin
+        x := x - dy;
+        px := px + sdx;
+      end;
+      py := py + sdy;
+    end;
+  end;
+end;
+
+// Draw a dashed line between x1,y1 and x2,y2 to the given surface
+// NOTE: The surface must be locked before calling this!
+
+procedure SDL_DrawLine( DstSurface : PSDL_Surface; x1, y1, x2, y2 : integer; Color :
+  cardinal; DashLength, DashSpace : byte ); overload;
+var
+  dx, dy, sdx, sdy, x, y, px, py, counter : integer; drawdash : boolean;
+begin
+  counter := 0;
+  drawdash := true; //begin line drawing with dash
+
+  //Avoid invalid user-passed dash parameters
+  if ( DashLength < 1 )
+    then
+    DashLength := 1;
+  if ( DashSpace < 1 )
+    then
+    DashSpace := 0;
+
+  dx := x2 - x1;
+  dy := y2 - y1;
+  if dx < 0 then
+    sdx := -1
+  else
+    sdx := 1;
+  if dy < 0 then
+    sdy := -1
+  else
+    sdy := 1;
+  dx := sdx * dx + 1;
+  dy := sdy * dy + 1;
+  x := 0;
+  y := 0;
+  px := x1;
+  py := y1;
+  if dx >= dy then
+  begin
+    for x := 0 to dx - 1 do
+    begin
+
+      //Alternate drawing dashes, or leaving spaces
+      if drawdash then
+      begin
+        SDL_PutPixel( DstSurface, px, py, Color );
+        inc( counter );
+        if ( counter > DashLength - 1 ) and ( DashSpace > 0 ) then
+        begin
+          drawdash := false;
+          counter := 0;
+        end;
+      end
+      else //space
+      begin
+        inc( counter );
+        if counter > DashSpace - 1 then
+        begin
+          drawdash := true;
+          counter := 0;
+        end;
+      end;
+
+      y := y + dy;
+      if y >= dx then
+      begin
+        y := y - dx;
+        py := py + sdy;
+      end;
+      px := px + sdx;
+    end;
+  end
+  else
+  begin
+    for y := 0 to dy - 1 do
+    begin
+
+      //Alternate drawing dashes, or leaving spaces
+      if drawdash then
+      begin
+        SDL_PutPixel( DstSurface, px, py, Color );
+        inc( counter );
+        if ( counter > DashLength - 1 ) and ( DashSpace > 0 ) then
+        begin
+          drawdash := false;
+          counter := 0;
+        end;
+      end
+      else //space
+      begin
+        inc( counter );
+        if counter > DashSpace - 1 then
+        begin
+          drawdash := true;
+          counter := 0;
+        end;
+      end;
+
+      x := x + dx;
+      if x >= dy then
+      begin
+        x := x - dy;
+        px := px + sdx;
+      end;
+      py := py + sdy;
+    end;
+  end;
+end;
+
+procedure SDL_AddLine( DstSurface : PSDL_Surface; x1, y1, x2, y2 : integer; Color :
+  cardinal );
+var
+  dx, dy, sdx, sdy, x, y, px, py : integer;
+begin
+  dx := x2 - x1;
+  dy := y2 - y1;
+  if dx < 0 then
+    sdx := -1
+  else
+    sdx := 1;
+  if dy < 0 then
+    sdy := -1
+  else
+    sdy := 1;
+  dx := sdx * dx + 1;
+  dy := sdy * dy + 1;
+  x := 0;
+  y := 0;
+  px := x1;
+  py := y1;
+  if dx >= dy then
+  begin
+    for x := 0 to dx - 1 do
+    begin
+      SDL_AddPixel( DstSurface, px, py, Color );
+      y := y + dy;
+      if y >= dx then
+      begin
+        y := y - dx;
+        py := py + sdy;
+      end;
+      px := px + sdx;
+    end;
+  end
+  else
+  begin
+    for y := 0 to dy - 1 do
+    begin
+      SDL_AddPixel( DstSurface, px, py, Color );
+      x := x + dx;
+      if x >= dy then
+      begin
+        x := x - dy;
+        px := px + sdx;
+      end;
+      py := py + sdy;
+    end;
+  end;
+end;
+
+procedure SDL_SubLine( DstSurface : PSDL_Surface; x1, y1, x2, y2 : integer; Color :
+  cardinal );
+var
+  dx, dy, sdx, sdy, x, y, px, py : integer;
+begin
+  dx := x2 - x1;
+  dy := y2 - y1;
+  if dx < 0 then
+    sdx := -1
+  else
+    sdx := 1;
+  if dy < 0 then
+    sdy := -1
+  else
+    sdy := 1;
+  dx := sdx * dx + 1;
+  dy := sdy * dy + 1;
+  x := 0;
+  y := 0;
+  px := x1;
+  py := y1;
+  if dx >= dy then
+  begin
+    for x := 0 to dx - 1 do
+    begin
+      SDL_SubPixel( DstSurface, px, py, Color );
+      y := y + dy;
+      if y >= dx then
+      begin
+        y := y - dx;
+        py := py + sdy;
+      end;
+      px := px + sdx;
+    end;
+  end
+  else
+  begin
+    for y := 0 to dy - 1 do
+    begin
+      SDL_SubPixel( DstSurface, px, py, Color );
+      x := x + dx;
+      if x >= dy then
+      begin
+        x := x - dy;
+        px := px + sdx;
+      end;
+      py := py + sdy;
+    end;
+  end;
+end;
+
+// flips a rectangle vertically on given surface
+
+procedure SDL_FlipRectV( DstSurface : PSDL_Surface; Rect : PSDL_Rect );
+var
+  TmpRect      : TSDL_Rect;
+  Locked       : boolean;
+  y, FlipLength, RowLength : integer;
+  Row1, Row2   : Pointer;
+  OneRow       : TByteArray; // Optimize it if you wish
+begin
+  if DstSurface <> nil then
+  begin
+    if Rect = nil then
+    begin // if Rect=nil then we flip the whole surface
+      TmpRect := SDLRect( 0, 0, DstSurface.w, DstSurface.h );
+      Rect := @TmpRect;
+    end;
+    FlipLength := Rect^.h shr 1 - 1;
+    RowLength := Rect^.w * DstSurface^.format.BytesPerPixel;
+    if SDL_MustLock( DstSurface ) then
+    begin
+      Locked := true;
+      SDL_LockSurface( DstSurface );
+    end
+    else
+      Locked := false;
+    Row1 := pointer( cardinal( DstSurface^.Pixels ) + UInt32( Rect^.y ) *
+      DstSurface^.Pitch );
+    Row2 := pointer( cardinal( DstSurface^.Pixels ) + ( UInt32( Rect^.y ) + Rect^.h - 1 )
+      * DstSurface^.Pitch );
+    for y := 0 to FlipLength do
+    begin
+      Move( Row1^, OneRow, RowLength );
+      Move( Row2^, Row1^, RowLength );
+      Move( OneRow, Row2^, RowLength );
+      inc( cardinal( Row1 ), DstSurface^.Pitch );
+      dec( cardinal( Row2 ), DstSurface^.Pitch );
+    end;
+    if Locked then
+      SDL_UnlockSurface( DstSurface );
+  end;
+end;
+
+// flips a rectangle horizontally on given surface
+
+procedure SDL_FlipRectH( DstSurface : PSDL_Surface; Rect : PSDL_Rect );
+type
+  T24bit = packed array[ 0..2 ] of byte;
+  T24bitArray = packed array[ 0..8191 ] of T24bit;
+  P24bitArray = ^T24bitArray;
+  TLongWordArray = array[ 0..8191 ] of LongWord;
+  PLongWordArray = ^TLongWordArray;
+var
+  TmpRect      : TSDL_Rect;
+  Row8bit      : PByteArray;
+  Row16bit     : PWordArray;
+  Row24bit     : P24bitArray;
+  Row32bit     : PLongWordArray;
+  y, x, RightSide, FlipLength : integer;
+  Pixel        : cardinal;
+  Pixel24      : T24bit;
+  Locked       : boolean;
+begin
+  if DstSurface <> nil then
+  begin
+    if Rect = nil then
+    begin
+      TmpRect := SDLRect( 0, 0, DstSurface.w, DstSurface.h );
+      Rect := @TmpRect;
+    end;
+    FlipLength := Rect^.w shr 1 - 1;
+    if SDL_MustLock( DstSurface ) then
+    begin
+      Locked := true;
+      SDL_LockSurface( DstSurface );
+    end
+    else
+      Locked := false;
+    case DstSurface^.format.BytesPerPixel of
+      1 :
+        begin
+          Row8Bit := pointer( cardinal( DstSurface^.pixels ) + UInt32( Rect^.y ) *
+            DstSurface^.pitch );
+          for y := 1 to Rect^.h do
+          begin
+            RightSide := Rect^.w - 1;
+            for x := 0 to FlipLength do
+            begin
+              Pixel := Row8Bit^[ x ];
+              Row8Bit^[ x ] := Row8Bit^[ RightSide ];
+              Row8Bit^[ RightSide ] := Pixel;
+              dec( RightSide );
+            end;
+            inc( cardinal( Row8Bit ), DstSurface^.pitch );
+          end;
+        end;
+      2 :
+        begin
+          Row16Bit := pointer( cardinal( DstSurface^.pixels ) + UInt32( Rect^.y ) *
+            DstSurface^.pitch );
+          for y := 1 to Rect^.h do
+          begin
+            RightSide := Rect^.w - 1;
+            for x := 0 to FlipLength do
+            begin
+              Pixel := Row16Bit^[ x ];
+              Row16Bit^[ x ] := Row16Bit^[ RightSide ];
+              Row16Bit^[ RightSide ] := Pixel;
+              dec( RightSide );
+            end;
+            inc( cardinal( Row16Bit ), DstSurface^.pitch );
+          end;
+        end;
+      3 :
+        begin
+          Row24Bit := pointer( cardinal( DstSurface^.pixels ) + UInt32( Rect^.y ) *
+            DstSurface^.pitch );
+          for y := 1 to Rect^.h do
+          begin
+            RightSide := Rect^.w - 1;
+            for x := 0 to FlipLength do
+            begin
+              Pixel24 := Row24Bit^[ x ];
+              Row24Bit^[ x ] := Row24Bit^[ RightSide ];
+              Row24Bit^[ RightSide ] := Pixel24;
+              dec( RightSide );
+            end;
+            inc( cardinal( Row24Bit ), DstSurface^.pitch );
+          end;
+        end;
+      4 :
+        begin
+          Row32Bit := pointer( cardinal( DstSurface^.pixels ) + UInt32( Rect^.y ) *
+            DstSurface^.pitch );
+          for y := 1 to Rect^.h do
+          begin
+            RightSide := Rect^.w - 1;
+            for x := 0 to FlipLength do
+            begin
+              Pixel := Row32Bit^[ x ];
+              Row32Bit^[ x ] := Row32Bit^[ RightSide ];
+              Row32Bit^[ RightSide ] := Pixel;
+              dec( RightSide );
+            end;
+            inc( cardinal( Row32Bit ), DstSurface^.pitch );
+          end;
+        end;
+    end;
+    if Locked then
+      SDL_UnlockSurface( DstSurface );
+  end;
+end;
+
+// Use with caution! The procedure allocates memory for TSDL_Rect and return with its pointer.
+// But you MUST free it after you don't need it anymore!!!
+
+function PSDLRect( aLeft, aTop, aWidth, aHeight : integer ) : PSDL_Rect;
+var
+  Rect         : PSDL_Rect;
+begin
+  New( Rect );
+  with Rect^ do
+  begin
+    x := aLeft;
+    y := aTop;
+    w := aWidth;
+    h := aHeight;
+  end;
+  Result := Rect;
+end;
+
+function SDLRect( aLeft, aTop, aWidth, aHeight : integer ) : TSDL_Rect;
+begin
+  with result do
+  begin
+    x := aLeft;
+    y := aTop;
+    w := aWidth;
+    h := aHeight;
+  end;
+end;
+
+function SDLRect( aRect : TRect ) : TSDL_Rect;
+begin
+  with aRect do
+    result := SDLRect( Left, Top, Right - Left, Bottom - Top );
+end;
+
+procedure SDL_Stretch8( Surface, Dst_Surface : PSDL_Surface; x1, x2, y1, y2, yr, yw,
+  depth : integer );
+var
+  dx, dy, e, d, dx2 : integer;
+  src_pitch, dst_pitch : uint16;
+  src_pixels, dst_pixels : PUint8;
+begin
+  if ( yw >= dst_surface^.h ) then
+    exit;
+  dx := ( x2 - x1 );
+  dy := ( y2 - y1 );
+  dy := dy shl 1;
+  e := dy - dx;
+  dx2 := dx shl 1;
+  src_pitch := Surface^.pitch;
+  dst_pitch := dst_surface^.pitch;
+  src_pixels := PUint8( integer( Surface^.pixels ) + yr * src_pitch + y1 * depth );
+  dst_pixels := PUint8( integer( dst_surface^.pixels ) + yw * dst_pitch + x1 *
+    depth );
+  for d := 0 to dx - 1 do
+  begin
+    move( src_pixels^, dst_pixels^, depth );
+    while ( e >= 0 ) do
+    begin
+      inc( src_pixels, depth );
+      e := e - dx2;
+    end;
+    inc( dst_pixels, depth );
+    e := e + dy;
+  end;
+end;
+
+function sign( x : integer ) : integer;
+begin
+  if x > 0 then
+    result := 1
+  else
+    result := -1;
+end;
+
+// Stretches a part of a surface
+
+function SDL_ScaleSurfaceRect( SrcSurface : PSDL_Surface; SrcX1, SrcY1, SrcW, SrcH,
+  Width, Height : integer ) : PSDL_Surface;
+var
+  dst_surface  : PSDL_Surface;
+  dx, dy, e, d, dx2, srcx2, srcy2 : integer;
+  destx1, desty1 : integer;
+begin
+  srcx2 := srcx1 + SrcW;
+  srcy2 := srcy1 + SrcH;
+  result := nil;
+  destx1 := 0;
+  desty1 := 0;
+  dx := abs( integer( Height - desty1 ) );
+  dy := abs( integer( SrcY2 - SrcY1 ) );
+  e := ( dy shl 1 ) - dx;
+  dx2 := dx shl 1;
+  dy := dy shl 1;
+  dst_surface := SDL_CreateRGBSurface( SDL_HWPALETTE, width - destx1, Height -
+    desty1,
+    SrcSurface^.Format^.BitsPerPixel,
+    SrcSurface^.Format^.RMask,
+    SrcSurface^.Format^.GMask,
+    SrcSurface^.Format^.BMask,
+    SrcSurface^.Format^.AMask );
+  if ( dst_surface^.format^.BytesPerPixel = 1 ) then
+    SDL_SetColors( dst_surface, @SrcSurface^.format^.palette^.colors^[ 0 ], 0, 256 );
+  SDL_SetColorKey( dst_surface, sdl_srccolorkey, SrcSurface^.format^.colorkey );
+  if ( SDL_MustLock( dst_surface ) ) then
+    if ( SDL_LockSurface( dst_surface ) < 0 ) then
+      exit;
+  for d := 0 to dx - 1 do
+  begin
+    SDL_Stretch8( SrcSurface, dst_surface, destx1, Width, SrcX1, SrcX2, SrcY1, desty1,
+      SrcSurface^.format^.BytesPerPixel );
+    while e >= 0 do
+    begin
+      inc( SrcY1 );
+      e := e - dx2;
+    end;
+    inc( desty1 );
+    e := e + dy;
+  end;
+  if SDL_MUSTLOCK( dst_surface ) then
+    SDL_UnlockSurface( dst_surface );
+  result := dst_surface;
+end;
+
+procedure SDL_MoveLine( Surface : PSDL_Surface; x1, x2, y1, xofs, depth : integer );
+var
+  src_pixels, dst_pixels : PUint8;
+  i            : integer;
+begin
+  src_pixels := PUint8( integer( Surface^.pixels ) + Surface^.w * y1 * depth + x2 *
+    depth );
+  dst_pixels := PUint8( integer( Surface^.pixels ) + Surface^.w * y1 * depth + ( x2
+    + xofs ) * depth );
+  for i := x2 downto x1 do
+  begin
+    move( src_pixels^, dst_pixels^, depth );
+    dec( src_pixels );
+    dec( dst_pixels );
+  end;
+end;
+{ Return the pixel value at (x, y)
+NOTE: The surface must be locked before calling this! }
+
+function SDL_GetPixel( SrcSurface : PSDL_Surface; x : integer; y : integer ) : Uint32;
+var
+  bpp          : UInt32;
+  p            : PInteger;
+begin
+  bpp := SrcSurface.format.BytesPerPixel;
+  // Here p is the address to the pixel we want to retrieve
+  p := Pointer( Uint32( SrcSurface.pixels ) + UInt32( y ) * SrcSurface.pitch + UInt32( x ) *
+    bpp );
+  case bpp of
+    1 : result := PUint8( p )^;
+    2 : result := PUint16( p )^;
+    3 :
+      if ( SDL_BYTEORDER = SDL_BIG_ENDIAN ) then
+        result := PUInt8Array( p )[ 0 ] shl 16 or PUInt8Array( p )[ 1 ] shl 8 or
+          PUInt8Array( p )[ 2 ]
+      else
+        result := PUInt8Array( p )[ 0 ] or PUInt8Array( p )[ 1 ] shl 8 or
+          PUInt8Array( p )[ 2 ] shl 16;
+    4 : result := PUint32( p )^;
+  else
+    result := 0; // shouldn't happen, but avoids warnings
+  end;
+end;
+{ Set the pixel at (x, y) to the given value
+  NOTE: The surface must be locked before calling this! }
+
+procedure SDL_PutPixel( DstSurface : PSDL_Surface; x : integer; y : integer; pixel :
+  Uint32 );
+var
+  bpp          : UInt32;
+  p            : PInteger;
+begin
+  bpp := DstSurface.format.BytesPerPixel;
+  p := Pointer( Uint32( DstSurface.pixels ) + UInt32( y ) * DstSurface.pitch + UInt32( x )
+    * bpp );
+  case bpp of
+    1 : PUint8( p )^ := pixel;
+    2 : PUint16( p )^ := pixel;
+    3 :
+      if ( SDL_BYTEORDER = SDL_BIG_ENDIAN ) then
+      begin
+        PUInt8Array( p )[ 0 ] := ( pixel shr 16 ) and $FF;
+        PUInt8Array( p )[ 1 ] := ( pixel shr 8 ) and $FF;
+        PUInt8Array( p )[ 2 ] := pixel and $FF;
+      end
+      else
+      begin
+        PUInt8Array( p )[ 0 ] := pixel and $FF;
+        PUInt8Array( p )[ 1 ] := ( pixel shr 8 ) and $FF;
+        PUInt8Array( p )[ 2 ] := ( pixel shr 16 ) and $FF;
+      end;
+    4 :
+      PUint32( p )^ := pixel;
+  end;
+end;
+
+procedure SDL_ScrollY( DstSurface : PSDL_Surface; DifY : integer );
+var
+  r1, r2       : TSDL_Rect;
+  //buffer: PSDL_Surface;
+  YPos         : Integer;
+begin
+  if ( DstSurface <> nil ) and ( DifY <> 0 ) then
+  begin
+    //if DifY > 0 then // going up
+    //begin
+    ypos := 0;
+    r1.x := 0;
+    r2.x := 0;
+    r1.w := DstSurface.w;
+    r2.w := DstSurface.w;
+    r1.h := DifY;
+    r2.h := DifY;
+    while ypos < DstSurface.h do
+    begin
+      r1.y := ypos;
+      r2.y := ypos + DifY;
+      SDL_BlitSurface( DstSurface, @r2, DstSurface, @r1 );
+      ypos := ypos + DifY;
+    end;
+    //end
+    //else
+    //begin // Going Down
+    //end;
+  end;
+end;
+
+{procedure SDL_ScrollY(Surface: PSDL_Surface; DifY: integer);
+var
+  r1, r2: TSDL_Rect;
+  buffer: PSDL_Surface;
+begin
+  if (Surface <> nil) and (Dify <> 0) then
+  begin
+    buffer := SDL_CreateRGBSurface(SDL_HWSURFACE, (Surface^.w - DifY) * 2,
+      Surface^.h * 2,
+      Surface^.Format^.BitsPerPixel, 0, 0, 0, 0);
+    if buffer <> nil then
+    begin
+      if (buffer^.format^.BytesPerPixel = 1) then
+        SDL_SetColors(buffer, @Surface^.format^.palette^.colors^[0], 0, 256);
+      r1 := SDLRect(0, DifY, buffer^.w, buffer^.h);
+      r2 := SDLRect(0, 0, buffer^.w, buffer^.h);
+      SDL_BlitSurface(Surface, @r1, buffer, @r2);
+      SDL_BlitSurface(buffer, @r2, Surface, @r2);
+      SDL_FreeSurface(buffer);
+    end;
+  end;
+end;}
+
+procedure SDL_ScrollX( DstSurface : PSDL_Surface; DifX : integer );
+var
+  r1, r2       : TSDL_Rect;
+  buffer       : PSDL_Surface;
+begin
+  if ( DstSurface <> nil ) and ( DifX <> 0 ) then
+  begin
+    buffer := SDL_CreateRGBSurface( SDL_HWSURFACE, ( DstSurface^.w - DifX ) * 2,
+      DstSurface^.h * 2,
+      DstSurface^.Format^.BitsPerPixel,
+      DstSurface^.Format^.RMask,
+      DstSurface^.Format^.GMask,
+      DstSurface^.Format^.BMask,
+      DstSurface^.Format^.AMask );
+    if buffer <> nil then
+    begin
+      if ( buffer^.format^.BytesPerPixel = 1 ) then
+        SDL_SetColors( buffer, @DstSurface^.format^.palette^.colors^[ 0 ], 0, 256 );
+      r1 := SDLRect( DifX, 0, buffer^.w, buffer^.h );
+      r2 := SDLRect( 0, 0, buffer^.w, buffer^.h );
+      SDL_BlitSurface( DstSurface, @r1, buffer, @r2 );
+      SDL_BlitSurface( buffer, @r2, DstSurface, @r2 );
+      SDL_FreeSurface( buffer );
+    end;
+  end;
+end;
+
+procedure SDL_RotateRad( DstSurface, SrcSurface : PSDL_Surface; SrcRect :
+  PSDL_Rect; DestX, DestY, OffsetX, OffsetY : Integer; Angle : Single );
+var
+  aSin, aCos   : Single;
+  MX, MY, DX, DY, NX, NY, SX, SY, OX, OY, Width, Height, TX, TY, RX, RY, ROX, ROY : Integer;
+  Colour, TempTransparentColour : UInt32;
+  MAXX, MAXY   : Integer;
+begin
+  // Rotate the surface to the target surface.
+  TempTransparentColour := SrcSurface.format.colorkey;
+  {if srcRect.w > srcRect.h then
+  begin
+    Width := srcRect.w;
+    Height := srcRect.w;
+  end
+  else
+  begin
+    Width := srcRect.h;
+    Height := srcRect.h;
+  end; }
+
+  maxx := DstSurface.w;
+  maxy := DstSurface.h;
+  aCos := cos( Angle );
+  aSin := sin( Angle );
+
+  Width := round( abs( srcrect.h * acos ) + abs( srcrect.w * asin ) );
+  Height := round( abs( srcrect.h * asin ) + abs( srcrect.w * acos ) );
+
+  OX := Width div 2;
+  OY := Height div 2; ;
+  MX := ( srcRect.x + ( srcRect.x + srcRect.w ) ) div 2;
+  MY := ( srcRect.y + ( srcRect.y + srcRect.h ) ) div 2;
+  ROX := ( -( srcRect.w div 2 ) ) + Offsetx;
+  ROY := ( -( srcRect.h div 2 ) ) + OffsetY;
+  Tx := ox + round( ROX * aSin - ROY * aCos );
+  Ty := oy + round( ROY * aSin + ROX * aCos );
+  SX := 0;
+  for DX := DestX - TX to DestX - TX + ( width ) do
+  begin
+    Inc( SX );
+    SY := 0;
+    for DY := DestY - TY to DestY - TY + ( Height ) do
+    begin
+      RX := SX - OX;
+      RY := SY - OY;
+      NX := round( mx + RX * aSin + RY * aCos ); //
+      NY := round( my + RY * aSin - RX * aCos ); //
+      // Used for testing only
+     //SDL_PutPixel(DestSurface.SDLSurfacePointer,DX,DY,0);
+      if ( ( DX > 0 ) and ( DX < MAXX ) ) and ( ( DY > 0 ) and ( DY < MAXY ) ) then
+      begin
+        if ( NX >= srcRect.x ) and ( NX <= srcRect.x + srcRect.w ) then
+        begin
+          if ( NY >= srcRect.y ) and ( NY <= srcRect.y + srcRect.h ) then
+          begin
+            Colour := SDL_GetPixel( SrcSurface, NX, NY );
+            if Colour <> TempTransparentColour then
+            begin
+              SDL_PutPixel( DstSurface, DX, DY, Colour );
+            end;
+          end;
+        end;
+      end;
+      inc( SY );
+    end;
+  end;
+end;
+
+procedure SDL_RotateDeg( DstSurface, SrcSurface : PSDL_Surface; SrcRect :
+  PSDL_Rect; DestX, DestY, OffsetX, OffsetY : Integer; Angle : Integer );
+begin
+  SDL_RotateRad( DstSurface, SrcSurface, SrcRect, DestX, DestY, OffsetX, OffsetY, DegToRad( Angle ) );
+end;
+
+function ValidateSurfaceRect( DstSurface : PSDL_Surface; dstrect : PSDL_Rect ) : TSDL_Rect;
+var
+  RealRect     : TSDL_Rect;
+  OutOfRange   : Boolean;
+begin
+  OutOfRange := false;
+  if dstrect = nil then
+  begin
+    RealRect.x := 0;
+    RealRect.y := 0;
+    RealRect.w := DstSurface.w;
+    RealRect.h := DstSurface.h;
+  end
+  else
+  begin
+    if dstrect.x < DstSurface.w then
+    begin
+      RealRect.x := dstrect.x;
+    end
+    else if dstrect.x < 0 then
+    begin
+      realrect.x := 0;
+    end
+    else
+    begin
+      OutOfRange := True;
+    end;
+    if dstrect.y < DstSurface.h then
+    begin
+      RealRect.y := dstrect.y;
+    end
+    else if dstrect.y < 0 then
+    begin
+      realrect.y := 0;
+    end
+    else
+    begin
+      OutOfRange := True;
+    end;
+    if OutOfRange = False then
+    begin
+      if realrect.x + dstrect.w <= DstSurface.w then
+      begin
+        RealRect.w := dstrect.w;
+      end
+      else
+      begin
+        RealRect.w := dstrect.w - realrect.x;
+      end;
+      if realrect.y + dstrect.h <= DstSurface.h then
+      begin
+        RealRect.h := dstrect.h;
+      end
+      else
+      begin
+        RealRect.h := dstrect.h - realrect.y;
+      end;
+    end;
+  end;
+  if OutOfRange = False then
+  begin
+    result := realrect;
+  end
+  else
+  begin
+    realrect.w := 0;
+    realrect.h := 0;
+    realrect.x := 0;
+    realrect.y := 0;
+    result := realrect;
+  end;
+end;
+
+procedure SDL_FillRectAdd( DstSurface : PSDL_Surface; dstrect : PSDL_Rect; color : UInt32 );
+var
+  RealRect     : TSDL_Rect;
+  Addr         : pointer;
+  ModX, BPP    : cardinal;
+  x, y, R, G, B, SrcColor : cardinal;
+begin
+  RealRect := ValidateSurfaceRect( DstSurface, DstRect );
+  if ( RealRect.w > 0 ) and ( RealRect.h > 0 ) then
+  begin
+    SDL_LockSurface( DstSurface );
+    BPP := DstSurface.format.BytesPerPixel;
+    with DstSurface^ do
+    begin
+      Addr := pointer( UInt32( pixels ) + UInt32( RealRect.y ) * pitch + UInt32( RealRect.x ) * BPP );
+      ModX := Pitch - UInt32( RealRect.w ) * BPP;
+    end;
+    case DstSurface.format.BitsPerPixel of
+      8 :
+        begin
+          for y := 0 to RealRect.h - 1 do
+          begin
+            for x := 0 to RealRect.w - 1 do
+            begin
+              SrcColor := PUInt32( Addr )^;
+              R := SrcColor and $E0 + Color and $E0;
+              G := SrcColor and $1C + Color and $1C;
+              B := SrcColor and $03 + Color and $03;
+              if R > $E0 then
+                R := $E0;
+              if G > $1C then
+                G := $1C;
+              if B > $03 then
+                B := $03;
+              PUInt8( Addr )^ := R or G or B;
+              inc( UInt32( Addr ), BPP );
+            end;
+            inc( UInt32( Addr ), ModX );
+          end;
+        end;
+      15 :
+        begin
+          for y := 0 to RealRect.h - 1 do
+          begin
+            for x := 0 to RealRect.w - 1 do
+            begin
+              SrcColor := PUInt32( Addr )^;
+              R := SrcColor and $7C00 + Color and $7C00;
+              G := SrcColor and $03E0 + Color and $03E0;
+              B := SrcColor and $001F + Color and $001F;
+              if R > $7C00 then
+                R := $7C00;
+              if G > $03E0 then
+                G := $03E0;
+              if B > $001F then
+                B := $001F;
+              PUInt16( Addr )^ := R or G or B;
+              inc( UInt32( Addr ), BPP );
+            end;
+            inc( UInt32( Addr ), ModX );
+          end;
+        end;
+      16 :
+        begin
+          for y := 0 to RealRect.h - 1 do
+          begin
+            for x := 0 to RealRect.w - 1 do
+            begin
+              SrcColor := PUInt32( Addr )^;
+              R := SrcColor and $F800 + Color and $F800;
+              G := SrcColor and $07C0 + Color and $07C0;
+              B := SrcColor and $001F + Color and $001F;
+              if R > $F800 then
+                R := $F800;
+              if G > $07C0 then
+                G := $07C0;
+              if B > $001F then
+                B := $001F;
+              PUInt16( Addr )^ := R or G or B;
+              inc( UInt32( Addr ), BPP );
+            end;
+            inc( UInt32( Addr ), ModX );
+          end;
+        end;
+      24 :
+        begin
+          for y := 0 to RealRect.h - 1 do
+          begin
+            for x := 0 to RealRect.w - 1 do
+            begin
+              SrcColor := PUInt32( Addr )^;
+              R := SrcColor and $00FF0000 + Color and $00FF0000;
+              G := SrcColor and $0000FF00 + Color and $0000FF00;
+              B := SrcColor and $000000FF + Color and $000000FF;
+              if R > $FF0000 then
+                R := $FF0000;
+              if G > $00FF00 then
+                G := $00FF00;
+              if B > $0000FF then
+                B := $0000FF;
+              PUInt32( Addr )^ := SrcColor and $FF000000 or R or G or B;
+              inc( UInt32( Addr ), BPP );
+            end;
+            inc( UInt32( Addr ), ModX );
+          end;
+        end;
+      32 :
+        begin
+          for y := 0 to RealRect.h - 1 do
+          begin
+            for x := 0 to RealRect.w - 1 do
+            begin
+              SrcColor := PUInt32( Addr )^;
+              R := SrcColor and $00FF0000 + Color and $00FF0000;
+              G := SrcColor and $0000FF00 + Color and $0000FF00;
+              B := SrcColor and $000000FF + Color and $000000FF;
+              if R > $FF0000 then
+                R := $FF0000;
+              if G > $00FF00 then
+                G := $00FF00;
+              if B > $0000FF then
+                B := $0000FF;
+              PUInt32( Addr )^ := R or G or B;
+              inc( UInt32( Addr ), BPP );
+            end;
+            inc( UInt32( Addr ), ModX );
+          end;
+        end;
+    end;
+    SDL_UnlockSurface( DstSurface );
+  end;
+end;
+
+procedure SDL_FillRectSub( DstSurface : PSDL_Surface; dstrect : PSDL_Rect; color : UInt32 );
+var
+  RealRect     : TSDL_Rect;
+  Addr         : pointer;
+  ModX, BPP    : cardinal;
+  x, y, R, G, B, SrcColor : cardinal;
+begin
+  RealRect := ValidateSurfaceRect( DstSurface, DstRect );
+  if ( RealRect.w > 0 ) and ( RealRect.h > 0 ) then
+  begin
+    SDL_LockSurface( DstSurface );
+    BPP := DstSurface.format.BytesPerPixel;
+    with DstSurface^ do
+    begin
+      Addr := pointer( UInt32( pixels ) + UInt32( RealRect.y ) * pitch + UInt32( RealRect.x ) * BPP );
+      ModX := Pitch - UInt32( RealRect.w ) * BPP;
+    end;
+    case DstSurface.format.BitsPerPixel of
+      8 :
+        begin
+          for y := 0 to RealRect.h - 1 do
+          begin
+            for x := 0 to RealRect.w - 1 do
+            begin
+              SrcColor := PUInt32( Addr )^;
+              R := SrcColor and $E0 - Color and $E0;
+              G := SrcColor and $1C - Color and $1C;
+              B := SrcColor and $03 - Color and $03;
+              if R > $E0 then
+                R := 0;
+              if G > $1C then
+                G := 0;
+              if B > $03 then
+                B := 0;
+              PUInt8( Addr )^ := R or G or B;
+              inc( UInt32( Addr ), BPP );
+            end;
+            inc( UInt32( Addr ), ModX );
+          end;
+        end;
+      15 :
+        begin
+          for y := 0 to RealRect.h - 1 do
+          begin
+            for x := 0 to RealRect.w - 1 do
+            begin
+              SrcColor := PUInt32( Addr )^;
+              R := SrcColor and $7C00 - Color and $7C00;
+              G := SrcColor and $03E0 - Color and $03E0;
+              B := SrcColor and $001F - Color and $001F;
+              if R > $7C00 then
+                R := 0;
+              if G > $03E0 then
+                G := 0;
+              if B > $001F then
+                B := 0;
+              PUInt16( Addr )^ := R or G or B;
+              inc( UInt32( Addr ), BPP );
+            end;
+            inc( UInt32( Addr ), ModX );
+          end;
+        end;
+      16 :
+        begin
+          for y := 0 to RealRect.h - 1 do
+          begin
+            for x := 0 to RealRect.w - 1 do
+            begin
+              SrcColor := PUInt32( Addr )^;
+              R := SrcColor and $F800 - Color and $F800;
+              G := SrcColor and $07C0 - Color and $07C0;
+              B := SrcColor and $001F - Color and $001F;
+              if R > $F800 then
+                R := 0;
+              if G > $07C0 then
+                G := 0;
+              if B > $001F then
+                B := 0;
+              PUInt16( Addr )^ := R or G or B;
+              inc( UInt32( Addr ), BPP );
+            end;
+            inc( UInt32( Addr ), ModX );
+          end;
+        end;
+      24 :
+        begin
+          for y := 0 to RealRect.h - 1 do
+          begin
+            for x := 0 to RealRect.w - 1 do
+            begin
+              SrcColor := PUInt32( Addr )^;
+              R := SrcColor and $00FF0000 - Color and $00FF0000;
+              G := SrcColor and $0000FF00 - Color and $0000FF00;
+              B := SrcColor and $000000FF - Color and $000000FF;
+              if R > $FF0000 then
+                R := 0;
+              if G > $00FF00 then
+                G := 0;
+              if B > $0000FF then
+                B := 0;
+              PUInt32( Addr )^ := SrcColor and $FF000000 or R or G or B;
+              inc( UInt32( Addr ), BPP );
+            end;
+            inc( UInt32( Addr ), ModX );
+          end;
+        end;
+      32 :
+        begin
+          for y := 0 to RealRect.h - 1 do
+          begin
+            for x := 0 to RealRect.w - 1 do
+            begin
+              SrcColor := PUInt32( Addr )^;
+              R := SrcColor and $00FF0000 - Color and $00FF0000;
+              G := SrcColor and $0000FF00 - Color and $0000FF00;
+              B := SrcColor and $000000FF - Color and $000000FF;
+              if R > $FF0000 then
+                R := 0;
+              if G > $00FF00 then
+                G := 0;
+              if B > $0000FF then
+                B := 0;
+              PUInt32( Addr )^ := R or G or B;
+              inc( UInt32( Addr ), BPP );
+            end;
+            inc( UInt32( Addr ), ModX );
+          end;
+        end;
+    end;
+    SDL_UnlockSurface( DstSurface );
+  end;
+end;
+
+procedure SDL_GradientFillRect( DstSurface : PSDL_Surface; const Rect : PSDL_Rect; const StartColor, EndColor : TSDL_Color; const Style : TGradientStyle );
+var
+  FBC          : array[ 0..255 ] of Cardinal;
+  // temp vars
+  i, YR, YG, YB, SR, SG, SB, DR, DG, DB : Integer;
+
+  TempStepV, TempStepH : Single;
+  TempLeft, TempTop, TempHeight, TempWidth : integer;
+  TempRect     : TSDL_Rect;
+
+begin
+  // calc FBC
+  YR := StartColor.r;
+  YG := StartColor.g;
+  YB := StartColor.b;
+  SR := YR;
+  SG := YG;
+  SB := YB;
+  DR := EndColor.r - SR;
+  DG := EndColor.g - SG;
+  DB := EndColor.b - SB;
+
+  for i := 0 to 255 do
+  begin
+    FBC[ i ] := SDL_MapRGB( DstSurface.format, YR, YG, YB );
+    YR := SR + round( DR / 255 * i );
+    YG := SG + round( DG / 255 * i );
+    YB := SB + round( DB / 255 * i );
+  end;
+
+  //  if aStyle = 1 then begin
+  TempStepH := Rect.w / 255;
+  TempStepV := Rect.h / 255;
+  TempHeight := Trunc( TempStepV + 1 );
+  TempWidth := Trunc( TempStepH + 1 );
+  TempTop := 0;
+  TempLeft := 0;
+  TempRect.x := Rect.x;
+  TempRect.y := Rect.y;
+  TempRect.h := Rect.h;
+  TempRect.w := Rect.w;
+
+  case Style of
+    gsHorizontal :
+      begin
+        TempRect.h := TempHeight;
+        for i := 0 to 255 do
+        begin
+          TempRect.y := Rect.y + TempTop;
+          SDL_FillRect( DstSurface, @TempRect, FBC[ i ] );
+          TempTop := Trunc( TempStepV * i );
+        end;
+      end;
+    gsVertical :
+      begin
+        TempRect.w := TempWidth;
+        for i := 0 to 255 do
+        begin
+          TempRect.x := Rect.x + TempLeft;
+          SDL_FillRect( DstSurface, @TempRect, FBC[ i ] );
+          TempLeft := Trunc( TempStepH * i );
+        end;
+      end;
+  end;
+end;
+
+procedure SDL_2xBlit( Src, Dest : PSDL_Surface );
+var
+  ReadAddr, WriteAddr, ReadRow, WriteRow : UInt32;
+  SrcPitch, DestPitch, x, y : UInt32;
+begin
+  if ( Src = nil ) or ( Dest = nil ) then
+    exit;
+  if ( Src.w shl 1 ) < Dest.w then
+    exit;
+  if ( Src.h shl 1 ) < Dest.h then
+    exit;
+
+  if SDL_MustLock( Src ) then
+    SDL_LockSurface( Src );
+  if SDL_MustLock( Dest ) then
+    SDL_LockSurface( Dest );
+
+  ReadRow := UInt32( Src.Pixels );
+  WriteRow := UInt32( Dest.Pixels );
+
+  SrcPitch := Src.pitch;
+  DestPitch := Dest.pitch;
+
+  case Src.format.BytesPerPixel of
+    1 : for y := 1 to Src.h do
+      begin
+        ReadAddr := ReadRow;
+        WriteAddr := WriteRow;
+        for x := 1 to Src.w do
+        begin
+          PUInt8( WriteAddr )^ := PUInt8( ReadAddr )^;
+          PUInt8( WriteAddr + 1 )^ := PUInt8( ReadAddr )^;
+          PUInt8( WriteAddr + DestPitch )^ := PUInt8( ReadAddr )^;
+          PUInt8( WriteAddr + DestPitch + 1 )^ := PUInt8( ReadAddr )^;
+          inc( ReadAddr );
+          inc( WriteAddr, 2 );
+        end;
+        inc( UInt32( ReadRow ), SrcPitch );
+        inc( UInt32( WriteRow ), DestPitch * 2 );
+      end;
+    2 : for y := 1 to Src.h do
+      begin
+        ReadAddr := ReadRow;
+        WriteAddr := WriteRow;
+        for x := 1 to Src.w do
+        begin
+          PUInt16( WriteAddr )^ := PUInt16( ReadAddr )^;
+          PUInt16( WriteAddr + 2 )^ := PUInt16( ReadAddr )^;
+          PUInt16( WriteAddr + DestPitch )^ := PUInt16( ReadAddr )^;
+          PUInt16( WriteAddr + DestPitch + 2 )^ := PUInt16( ReadAddr )^;
+          inc( ReadAddr, 2 );
+          inc( WriteAddr, 4 );
+        end;
+        inc( UInt32( ReadRow ), SrcPitch );
+        inc( UInt32( WriteRow ), DestPitch * 2 );
+      end;
+    3 : for y := 1 to Src.h do
+      begin
+        ReadAddr := ReadRow;
+        WriteAddr := WriteRow;
+        for x := 1 to Src.w do
+        begin
+          PUInt32( WriteAddr )^ := ( PUInt32( WriteAddr )^ and $FF000000 ) or ( PUInt32( ReadAddr )^ and $00FFFFFF );
+          PUInt32( WriteAddr + 3 )^ := ( PUInt32( WriteAddr + 3 )^ and $FF000000 ) or ( PUInt32( ReadAddr )^ and $00FFFFFF );
+          PUInt32( WriteAddr + DestPitch )^ := ( PUInt32( WriteAddr + DestPitch )^ and $FF000000 ) or ( PUInt32( ReadAddr )^ and $00FFFFFF );
+          PUInt32( WriteAddr + DestPitch + 3 )^ := ( PUInt32( WriteAddr + DestPitch + 3 )^ and $FF000000 ) or ( PUInt32( ReadAddr )^ and $00FFFFFF );
+          inc( ReadAddr, 3 );
+          inc( WriteAddr, 6 );
+        end;
+        inc( UInt32( ReadRow ), SrcPitch );
+        inc( UInt32( WriteRow ), DestPitch * 2 );
+      end;
+    4 : for y := 1 to Src.h do
+      begin
+        ReadAddr := ReadRow;
+        WriteAddr := WriteRow;
+        for x := 1 to Src.w do
+        begin
+          PUInt32( WriteAddr )^ := PUInt32( ReadAddr )^;
+          PUInt32( WriteAddr + 4 )^ := PUInt32( ReadAddr )^;
+          PUInt32( WriteAddr + DestPitch )^ := PUInt32( ReadAddr )^;
+          PUInt32( WriteAddr + DestPitch + 4 )^ := PUInt32( ReadAddr )^;
+          inc( ReadAddr, 4 );
+          inc( WriteAddr, 8 );
+        end;
+        inc( UInt32( ReadRow ), SrcPitch );
+        inc( UInt32( WriteRow ), DestPitch * 2 );
+      end;
+  end;
+
+  if SDL_MustLock( Src ) then
+    SDL_UnlockSurface( Src );
+  if SDL_MustLock( Dest ) then
+    SDL_UnlockSurface( Dest );
+end;
+
+procedure SDL_Scanline2xBlit( Src, Dest : PSDL_Surface );
+var
+  ReadAddr, WriteAddr, ReadRow, WriteRow : UInt32;
+  SrcPitch, DestPitch, x, y : UInt32;
+begin
+  if ( Src = nil ) or ( Dest = nil ) then
+    exit;
+  if ( Src.w shl 1 ) < Dest.w then
+    exit;
+  if ( Src.h shl 1 ) < Dest.h then
+    exit;
+
+  if SDL_MustLock( Src ) then
+    SDL_LockSurface( Src );
+  if SDL_MustLock( Dest ) then
+    SDL_LockSurface( Dest );
+
+  ReadRow := UInt32( Src.Pixels );
+  WriteRow := UInt32( Dest.Pixels );
+
+  SrcPitch := Src.pitch;
+  DestPitch := Dest.pitch;
+
+  case Src.format.BytesPerPixel of
+    1 : for y := 1 to Src.h do
+      begin
+        ReadAddr := ReadRow;
+        WriteAddr := WriteRow;
+        for x := 1 to Src.w do
+        begin
+          PUInt8( WriteAddr )^ := PUInt8( ReadAddr )^;
+          PUInt8( WriteAddr + 1 )^ := PUInt8( ReadAddr )^;
+          inc( ReadAddr );
+          inc( WriteAddr, 2 );
+        end;
+        inc( UInt32( ReadRow ), SrcPitch );
+        inc( UInt32( WriteRow ), DestPitch * 2 );
+      end;
+    2 : for y := 1 to Src.h do
+      begin
+        ReadAddr := ReadRow;
+        WriteAddr := WriteRow;
+        for x := 1 to Src.w do
+        begin
+          PUInt16( WriteAddr )^ := PUInt16( ReadAddr )^;
+          PUInt16( WriteAddr + 2 )^ := PUInt16( ReadAddr )^;
+          inc( ReadAddr, 2 );
+          inc( WriteAddr, 4 );
+        end;
+        inc( UInt32( ReadRow ), SrcPitch );
+        inc( UInt32( WriteRow ), DestPitch * 2 );
+      end;
+    3 : for y := 1 to Src.h do
+      begin
+        ReadAddr := ReadRow;
+        WriteAddr := WriteRow;
+        for x := 1 to Src.w do
+        begin
+          PUInt32( WriteAddr )^ := ( PUInt32( WriteAddr )^ and $FF000000 ) or ( PUInt32( ReadAddr )^ and $00FFFFFF );
+          PUInt32( WriteAddr + 3 )^ := ( PUInt32( WriteAddr + 3 )^ and $FF000000 ) or ( PUInt32( ReadAddr )^ and $00FFFFFF );
+          inc( ReadAddr, 3 );
+          inc( WriteAddr, 6 );
+        end;
+        inc( UInt32( ReadRow ), SrcPitch );
+        inc( UInt32( WriteRow ), DestPitch * 2 );
+      end;
+    4 : for y := 1 to Src.h do
+      begin
+        ReadAddr := ReadRow;
+        WriteAddr := WriteRow;
+        for x := 1 to Src.w do
+        begin
+          PUInt32( WriteAddr )^ := PUInt32( ReadAddr )^;
+          PUInt32( WriteAddr + 4 )^ := PUInt32( ReadAddr )^;
+          inc( ReadAddr, 4 );
+          inc( WriteAddr, 8 );
+        end;
+        inc( UInt32( ReadRow ), SrcPitch );
+        inc( UInt32( WriteRow ), DestPitch * 2 );
+      end;
+  end;
+
+  if SDL_MustLock( Src ) then
+    SDL_UnlockSurface( Src );
+  if SDL_MustLock( Dest ) then
+    SDL_UnlockSurface( Dest );
+end;
+
+procedure SDL_50Scanline2xBlit( Src, Dest : PSDL_Surface );
+var
+  ReadAddr, WriteAddr, ReadRow, WriteRow : UInt32;
+  SrcPitch, DestPitch, x, y, Color : UInt32;
+begin
+  if ( Src = nil ) or ( Dest = nil ) then
+    exit;
+  if ( Src.w shl 1 ) < Dest.w then
+    exit;
+  if ( Src.h shl 1 ) < Dest.h then
+    exit;
+
+  if SDL_MustLock( Src ) then
+    SDL_LockSurface( Src );
+  if SDL_MustLock( Dest ) then
+    SDL_LockSurface( Dest );
+
+  ReadRow := UInt32( Src.Pixels );
+  WriteRow := UInt32( Dest.Pixels );
+
+  SrcPitch := Src.pitch;
+  DestPitch := Dest.pitch;
+
+  case Src.format.BitsPerPixel of
+    8 : for y := 1 to Src.h do
+      begin
+        ReadAddr := ReadRow;
+        WriteAddr := WriteRow;
+        for x := 1 to Src.w do
+        begin
+          Color := PUInt8( ReadAddr )^;
+          PUInt8( WriteAddr )^ := Color;
+          PUInt8( WriteAddr + 1 )^ := Color;
+          Color := ( Color shr 1 ) and $6D; {%01101101}
+          PUInt8( WriteAddr + DestPitch )^ := Color;
+          PUInt8( WriteAddr + DestPitch + 1 )^ := Color;
+          inc( ReadAddr );
+          inc( WriteAddr, 2 );
+        end;
+        inc( UInt32( ReadRow ), SrcPitch );
+        inc( UInt32( WriteRow ), DestPitch * 2 );
+      end;
+    15 : for y := 1 to Src.h do
+      begin
+        ReadAddr := ReadRow;
+        WriteAddr := WriteRow;
+        for x := 1 to Src.w do
+        begin
+          Color := PUInt16( ReadAddr )^;
+          PUInt16( WriteAddr )^ := Color;
+          PUInt16( WriteAddr + 2 )^ := Color;
+          Color := ( Color shr 1 ) and $3DEF; {%0011110111101111}
+          PUInt16( WriteAddr + DestPitch )^ := Color;
+          PUInt16( WriteAddr + DestPitch + 2 )^ := Color;
+          inc( ReadAddr, 2 );
+          inc( WriteAddr, 4 );
+        end;
+        inc( UInt32( ReadRow ), SrcPitch );
+        inc( UInt32( WriteRow ), DestPitch * 2 );
+      end;
+    16 : for y := 1 to Src.h do
+      begin
+        ReadAddr := ReadRow;
+        WriteAddr := WriteRow;
+        for x := 1 to Src.w do
+        begin
+          Color := PUInt16( ReadAddr )^;
+          PUInt16( WriteAddr )^ := Color;
+          PUInt16( WriteAddr + 2 )^ := Color;
+          Color := ( Color shr 1 ) and $7BEF; {%0111101111101111}
+          PUInt16( WriteAddr + DestPitch )^ := Color;
+          PUInt16( WriteAddr + DestPitch + 2 )^ := Color;
+          inc( ReadAddr, 2 );
+          inc( WriteAddr, 4 );
+        end;
+        inc( UInt32( ReadRow ), SrcPitch );
+        inc( UInt32( WriteRow ), DestPitch * 2 );
+      end;
+    24 : for y := 1 to Src.h do
+      begin
+        ReadAddr := ReadRow;
+        WriteAddr := WriteRow;
+        for x := 1 to Src.w do
+        begin
+          Color := ( PUInt32( WriteAddr )^ and $FF000000 ) or ( PUInt32( ReadAddr )^ and $00FFFFFF );
+          PUInt32( WriteAddr )^ := Color;
+          PUInt32( WriteAddr + 3 )^ := Color;
+          Color := ( Color shr 1 ) and $007F7F7F; {%011111110111111101111111}
+          PUInt32( WriteAddr + DestPitch )^ := Color;
+          PUInt32( WriteAddr + DestPitch + 3 )^ := Color;
+          inc( ReadAddr, 3 );
+          inc( WriteAddr, 6 );
+        end;
+        inc( UInt32( ReadRow ), SrcPitch );
+        inc( UInt32( WriteRow ), DestPitch * 2 );
+      end;
+    32 : for y := 1 to Src.h do
+      begin
+        ReadAddr := ReadRow;
+        WriteAddr := WriteRow;
+        for x := 1 to Src.w do
+        begin
+          Color := PUInt32( ReadAddr )^;
+          PUInt32( WriteAddr )^ := Color;
+          PUInt32( WriteAddr + 4 )^ := Color;
+          Color := ( Color shr 1 ) and $7F7F7F7F;
+          PUInt32( WriteAddr + DestPitch )^ := Color;
+          PUInt32( WriteAddr + DestPitch + 4 )^ := Color;
+          inc( ReadAddr, 4 );
+          inc( WriteAddr, 8 );
+        end;
+        inc( UInt32( ReadRow ), SrcPitch );
+        inc( UInt32( WriteRow ), DestPitch * 2 );
+      end;
+  end;
+
+  if SDL_MustLock( Src ) then
+    SDL_UnlockSurface( Src );
+  if SDL_MustLock( Dest ) then
+    SDL_UnlockSurface( Dest );
+end;
+
+function SDL_PixelTestSurfaceVsRect( SrcSurface1 : PSDL_Surface; SrcRect1 :
+  PSDL_Rect; SrcRect2 : PSDL_Rect; Left1, Top1, Left2, Top2 : integer ) :
+  boolean;
+var
+  Src_Rect1, Src_Rect2 : TSDL_Rect;
+  right1, bottom1 : integer;
+  right2, bottom2 : integer;
+  Scan1Start, {Scan2Start,} ScanWidth, ScanHeight : cardinal;
+  Mod1         : cardinal;
+  Addr1        : cardinal;
+  BPP          : cardinal;
+  Pitch1       : cardinal;
+  TransparentColor1 : cardinal;
+  tx, ty       : cardinal;
+// StartTick    : cardinal; // Auto Removed, Unused Variable
+  Color1       : cardinal;
+begin
+  Result := false;
+  if SrcRect1 = nil then
+  begin
+    with Src_Rect1 do
+    begin
+      x := 0;
+      y := 0;
+      w := SrcSurface1.w;
+      h := SrcSurface1.h;
+    end;
+  end
+  else
+    Src_Rect1 := SrcRect1^;
+
+  Src_Rect2 := SrcRect2^;
+  with Src_Rect1 do
+  begin
+    Right1 := Left1 + w;
+    Bottom1 := Top1 + h;
+  end;
+  with Src_Rect2 do
+  begin
+    Right2 := Left2 + w;
+    Bottom2 := Top2 + h;
+  end;
+  if ( Left1 >= Right2 ) or ( Right1 <= Left2 ) or ( Top1 >= Bottom2 ) or ( Bottom1 <= Top2 ) then
+    exit;
+  if Left1 <= Left2 then
+  begin
+    // 1. left, 2. right
+    Scan1Start := Src_Rect1.x + Left2 - Left1;
+    //Scan2Start := Src_Rect2.x;
+    ScanWidth := Right1 - Left2;
+    with Src_Rect2 do
+      if ScanWidth > w then
+        ScanWidth := w;
+  end
+  else
+  begin
+    // 1. right, 2. left
+    Scan1Start := Src_Rect1.x;
+    //Scan2Start := Src_Rect2.x + Left1 - Left2;
+    ScanWidth := Right2 - Left1;
+    with Src_Rect1 do
+      if ScanWidth > w then
+        ScanWidth := w;
+  end;
+  with SrcSurface1^ do
+  begin
+    Pitch1 := Pitch;
+    Addr1 := cardinal( Pixels );
+    inc( Addr1, Pitch1 * UInt32( Src_Rect1.y ) );
+    with format^ do
+    begin
+      BPP := BytesPerPixel;
+      TransparentColor1 := colorkey;
+    end;
+  end;
+
+  Mod1 := Pitch1 - ( ScanWidth * BPP );
+
+  inc( Addr1, BPP * Scan1Start );
+
+  if Top1 <= Top2 then
+  begin
+    // 1. up, 2. down
+    ScanHeight := Bottom1 - Top2;
+    if ScanHeight > Src_Rect2.h then
+      ScanHeight := Src_Rect2.h;
+    inc( Addr1, Pitch1 * UInt32( Top2 - Top1 ) );
+  end
+  else
+  begin
+    // 1. down, 2. up
+    ScanHeight := Bottom2 - Top1;
+    if ScanHeight > Src_Rect1.h then
+      ScanHeight := Src_Rect1.h;
+
+  end;
+  case BPP of
+    1 :
+      for ty := 1 to ScanHeight do
+      begin
+        for tx := 1 to ScanWidth do
+        begin
+          if ( PByte( Addr1 )^ <> TransparentColor1 ) then
+          begin
+            Result := true;
+            exit;
+          end;
+          inc( Addr1 );
+
+        end;
+        inc( Addr1, Mod1 );
+
+      end;
+    2 :
+      for ty := 1 to ScanHeight do
+      begin
+        for tx := 1 to ScanWidth do
+        begin
+          if ( PWord( Addr1 )^ <> TransparentColor1 ) then
+          begin
+            Result := true;
+            exit;
+          end;
+          inc( Addr1, 2 );
+
+        end;
+        inc( Addr1, Mod1 );
+
+      end;
+    3 :
+      for ty := 1 to ScanHeight do
+      begin
+        for tx := 1 to ScanWidth do
+        begin
+          Color1 := PLongWord( Addr1 )^ and $00FFFFFF;
+
+          if ( Color1 <> TransparentColor1 )
+            then
+          begin
+            Result := true;
+            exit;
+          end;
+          inc( Addr1, 3 );
+
+        end;
+        inc( Addr1, Mod1 );
+
+      end;
+    4 :
+      for ty := 1 to ScanHeight do
+      begin
+        for tx := 1 to ScanWidth do
+        begin
+          if ( PLongWord( Addr1 )^ <> TransparentColor1 ) then
+          begin
+            Result := true;
+            exit;
+          end;
+          inc( Addr1, 4 );
+
+        end;
+        inc( Addr1, Mod1 );
+
+      end;
+  end;
+end;
+
+procedure SDL_ORSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;
+  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );
+var
+{*R, *}{*G, *}{*B, *}Pixel1, Pixel2, TransparentColor : cardinal; // Auto Removed, Unused Variable (R) // Auto Removed, Unused Variable (G) // Auto Removed, Unused Variable (B)
+  Src, Dest    : TSDL_Rect;
+  Diff         : integer;
+  SrcAddr, DestAddr : cardinal;
+  WorkX, WorkY : word;
+  SrcMod, DestMod : cardinal;
+  Bits         : cardinal;
+begin
+  if ( SrcSurface = nil ) or ( DestSurface = nil ) then
+    exit; // Remove this to make it faster
+  if ( SrcSurface.Format.BitsPerPixel <> DestSurface.Format.BitsPerPixel ) then
+    exit; // Remove this to make it faster
+  if SrcRect = nil then
+  begin
+    with Src do
+    begin
+      x := 0;
+      y := 0;
+      w := SrcSurface.w;
+      h := SrcSurface.h;
+    end;
+  end
+  else
+    Src := SrcRect^;
+  if DestRect = nil then
+  begin
+    Dest.x := 0;
+    Dest.y := 0;
+  end
+  else
+    Dest := DestRect^;
+  Dest.w := Src.w;
+  Dest.h := Src.h;
+  with DestSurface.Clip_Rect do
+  begin
+    // Source's right side is greater than the dest.cliprect
+    if Dest.x + Src.w > x + w then
+    begin
+      smallint( Src.w ) := x + w - Dest.x;
+      smallint( Dest.w ) := x + w - Dest.x;
+      if smallint( Dest.w ) < 1 then
+        exit;
+    end;
+    // Source's bottom side is greater than the dest.clip
+    if Dest.y + Src.h > y + h then
+    begin
+      smallint( Src.h ) := y + h - Dest.y;
+      smallint( Dest.h ) := y + h - Dest.y;
+      if smallint( Dest.h ) < 1 then
+        exit;
+    end;
+    // Source's left side is less than the dest.clip
+    if Dest.x < x then
+    begin
+      Diff := x - Dest.x;
+      Src.x := Src.x + Diff;
+      smallint( Src.w ) := smallint( Src.w ) - Diff;
+      Dest.x := x;
+      smallint( Dest.w ) := smallint( Dest.w ) - Diff;
+      if smallint( Dest.w ) < 1 then
+        exit;
+    end;
+    // Source's Top side is less than the dest.clip
+    if Dest.y < y then
+    begin
+      Diff := y - Dest.y;
+      Src.y := Src.y + Diff;
+      smallint( Src.h ) := smallint( Src.h ) - Diff;
+      Dest.y := y;
+      smallint( Dest.h ) := smallint( Dest.h ) - Diff;
+      if smallint( Dest.h ) < 1 then
+        exit;
+    end;
+  end;
+  with SrcSurface^ do
+  begin
+    SrcAddr := cardinal( Pixels ) + UInt32( Src.y ) * Pitch + UInt32( Src.x ) *
+      Format.BytesPerPixel;
+    SrcMod := Pitch - Src.w * Format.BytesPerPixel;
+    TransparentColor := Format.colorkey;
+  end;
+  with DestSurface^ do
+  begin
+    DestAddr := cardinal( Pixels ) + UInt32( Dest.y ) * Pitch + UInt32( Dest.x ) *
+      Format.BytesPerPixel;
+    DestMod := Pitch - Dest.w * Format.BytesPerPixel;
+    Bits := Format.BitsPerPixel;
+  end;
+  SDL_LockSurface( SrcSurface );
+  SDL_LockSurface( DestSurface );
+  WorkY := Src.h;
+  case bits of
+    8 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt8( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt8( DestAddr )^;
+              PUInt8( DestAddr )^ := Pixel2 or Pixel1;
+            end;
+            inc( SrcAddr );
+            inc( DestAddr );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    15 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt16( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt16( DestAddr )^;
+
+              PUInt16( DestAddr )^ := Pixel2 or Pixel1;
+
+            end;
+            inc( SrcAddr, 2 );
+            inc( DestAddr, 2 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    16 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt16( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt16( DestAddr )^;
+
+              PUInt16( DestAddr )^ := Pixel2 or Pixel1;
+
+            end;
+            inc( SrcAddr, 2 );
+            inc( DestAddr, 2 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    24 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt32( SrcAddr )^ and $00FFFFFF;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt32( DestAddr )^ and $00FFFFFF;
+
+              PUInt32( DestAddr )^ := PUInt32( DestAddr )^ and $FF000000 or Pixel2 or Pixel1;
+            end;
+            inc( SrcAddr, 3 );
+            inc( DestAddr, 3 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    32 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt32( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt32( DestAddr )^;
+
+              PUInt32( DestAddr )^ := Pixel2 or Pixel1;
+            end;
+            inc( SrcAddr, 4 );
+            inc( DestAddr, 4 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+  end;
+  SDL_UnlockSurface( SrcSurface );
+  SDL_UnlockSurface( DestSurface );
+end;
+
+procedure SDL_ANDSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;
+  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );
+var
+{*R, *}{*G, *}{*B, *}Pixel1, Pixel2, TransparentColor : cardinal; // Auto Removed, Unused Variable (R) // Auto Removed, Unused Variable (G) // Auto Removed, Unused Variable (B)
+  Src, Dest    : TSDL_Rect;
+  Diff         : integer;
+  SrcAddr, DestAddr : cardinal;
+  WorkX, WorkY : word;
+  SrcMod, DestMod : cardinal;
+  Bits         : cardinal;
+begin
+  if ( SrcSurface = nil ) or ( DestSurface = nil ) then
+    exit; // Remove this to make it faster
+  if ( SrcSurface.Format.BitsPerPixel <> DestSurface.Format.BitsPerPixel ) then
+    exit; // Remove this to make it faster
+  if SrcRect = nil then
+  begin
+    with Src do
+    begin
+      x := 0;
+      y := 0;
+      w := SrcSurface.w;
+      h := SrcSurface.h;
+    end;
+  end
+  else
+    Src := SrcRect^;
+  if DestRect = nil then
+  begin
+    Dest.x := 0;
+    Dest.y := 0;
+  end
+  else
+    Dest := DestRect^;
+  Dest.w := Src.w;
+  Dest.h := Src.h;
+  with DestSurface.Clip_Rect do
+  begin
+    // Source's right side is greater than the dest.cliprect
+    if Dest.x + Src.w > x + w then
+    begin
+      smallint( Src.w ) := x + w - Dest.x;
+      smallint( Dest.w ) := x + w - Dest.x;
+      if smallint( Dest.w ) < 1 then
+        exit;
+    end;
+    // Source's bottom side is greater than the dest.clip
+    if Dest.y + Src.h > y + h then
+    begin
+      smallint( Src.h ) := y + h - Dest.y;
+      smallint( Dest.h ) := y + h - Dest.y;
+      if smallint( Dest.h ) < 1 then
+        exit;
+    end;
+    // Source's left side is less than the dest.clip
+    if Dest.x < x then
+    begin
+      Diff := x - Dest.x;
+      Src.x := Src.x + Diff;
+      smallint( Src.w ) := smallint( Src.w ) - Diff;
+      Dest.x := x;
+      smallint( Dest.w ) := smallint( Dest.w ) - Diff;
+      if smallint( Dest.w ) < 1 then
+        exit;
+    end;
+    // Source's Top side is less than the dest.clip
+    if Dest.y < y then
+    begin
+      Diff := y - Dest.y;
+      Src.y := Src.y + Diff;
+      smallint( Src.h ) := smallint( Src.h ) - Diff;
+      Dest.y := y;
+      smallint( Dest.h ) := smallint( Dest.h ) - Diff;
+      if smallint( Dest.h ) < 1 then
+        exit;
+    end;
+  end;
+  with SrcSurface^ do
+  begin
+    SrcAddr := cardinal( Pixels ) + UInt32( Src.y ) * Pitch + UInt32( Src.x ) *
+      Format.BytesPerPixel;
+    SrcMod := Pitch - Src.w * Format.BytesPerPixel;
+    TransparentColor := Format.colorkey;
+  end;
+  with DestSurface^ do
+  begin
+    DestAddr := cardinal( Pixels ) + UInt32( Dest.y ) * Pitch + UInt32( Dest.x ) *
+      Format.BytesPerPixel;
+    DestMod := Pitch - Dest.w * Format.BytesPerPixel;
+    Bits := Format.BitsPerPixel;
+  end;
+  SDL_LockSurface( SrcSurface );
+  SDL_LockSurface( DestSurface );
+  WorkY := Src.h;
+  case bits of
+    8 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt8( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt8( DestAddr )^;
+              PUInt8( DestAddr )^ := Pixel2 and Pixel1;
+            end;
+            inc( SrcAddr );
+            inc( DestAddr );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    15 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt16( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt16( DestAddr )^;
+
+              PUInt16( DestAddr )^ := Pixel2 and Pixel1;
+
+            end;
+            inc( SrcAddr, 2 );
+            inc( DestAddr, 2 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    16 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt16( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt16( DestAddr )^;
+
+              PUInt16( DestAddr )^ := Pixel2 and Pixel1;
+
+            end;
+            inc( SrcAddr, 2 );
+            inc( DestAddr, 2 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    24 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt32( SrcAddr )^ and $00FFFFFF;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt32( DestAddr )^ and $00FFFFFF;
+
+              PUInt32( DestAddr )^ := PUInt32( DestAddr )^ and $FF000000 or Pixel2 and Pixel1;
+            end;
+            inc( SrcAddr, 3 );
+            inc( DestAddr, 3 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    32 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt32( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt32( DestAddr )^;
+
+              PUInt32( DestAddr )^ := Pixel2 and Pixel1;
+            end;
+            inc( SrcAddr, 4 );
+            inc( DestAddr, 4 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+  end;
+  SDL_UnlockSurface( SrcSurface );
+  SDL_UnlockSurface( DestSurface );
+end;
+
+
+
+procedure SDL_GTSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;
+  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );
+var
+  R, G, B, Pixel1, Pixel2, TransparentColor : cardinal;
+  Src, Dest    : TSDL_Rect;
+  Diff         : integer;
+  SrcAddr, DestAddr : cardinal;
+  WorkX, WorkY : word;
+  SrcMod, DestMod : cardinal;
+  Bits         : cardinal;
+begin
+  if ( SrcSurface = nil ) or ( DestSurface = nil ) then
+    exit; // Remove this to make it faster
+  if ( SrcSurface.Format.BitsPerPixel <> DestSurface.Format.BitsPerPixel ) then
+    exit; // Remove this to make it faster
+  if SrcRect = nil then
+  begin
+    with Src do
+    begin
+      x := 0;
+      y := 0;
+      w := SrcSurface.w;
+      h := SrcSurface.h;
+    end;
+  end
+  else
+    Src := SrcRect^;
+  if DestRect = nil then
+  begin
+    Dest.x := 0;
+    Dest.y := 0;
+  end
+  else
+    Dest := DestRect^;
+  Dest.w := Src.w;
+  Dest.h := Src.h;
+  with DestSurface.Clip_Rect do
+  begin
+    // Source's right side is greater than the dest.cliprect
+    if Dest.x + Src.w > x + w then
+    begin
+      smallint( Src.w ) := x + w - Dest.x;
+      smallint( Dest.w ) := x + w - Dest.x;
+      if smallint( Dest.w ) < 1 then
+        exit;
+    end;
+    // Source's bottom side is greater than the dest.clip
+    if Dest.y + Src.h > y + h then
+    begin
+      smallint( Src.h ) := y + h - Dest.y;
+      smallint( Dest.h ) := y + h - Dest.y;
+      if smallint( Dest.h ) < 1 then
+        exit;
+    end;
+    // Source's left side is less than the dest.clip
+    if Dest.x < x then
+    begin
+      Diff := x - Dest.x;
+      Src.x := Src.x + Diff;
+      smallint( Src.w ) := smallint( Src.w ) - Diff;
+      Dest.x := x;
+      smallint( Dest.w ) := smallint( Dest.w ) - Diff;
+      if smallint( Dest.w ) < 1 then
+        exit;
+    end;
+    // Source's Top side is less than the dest.clip
+    if Dest.y < y then
+    begin
+      Diff := y - Dest.y;
+      Src.y := Src.y + Diff;
+      smallint( Src.h ) := smallint( Src.h ) - Diff;
+      Dest.y := y;
+      smallint( Dest.h ) := smallint( Dest.h ) - Diff;
+      if smallint( Dest.h ) < 1 then
+        exit;
+    end;
+  end;
+  with SrcSurface^ do
+  begin
+    SrcAddr := cardinal( Pixels ) + UInt32( Src.y ) * Pitch + UInt32( Src.x ) *
+      Format.BytesPerPixel;
+    SrcMod := Pitch - Src.w * Format.BytesPerPixel;
+    TransparentColor := Format.colorkey;
+  end;
+  with DestSurface^ do
+  begin
+    DestAddr := cardinal( Pixels ) + UInt32( Dest.y ) * Pitch + UInt32( Dest.x ) *
+      Format.BytesPerPixel;
+    DestMod := Pitch - Dest.w * Format.BytesPerPixel;
+    Bits := Format.BitsPerPixel;
+  end;
+  SDL_LockSurface( SrcSurface );
+  SDL_LockSurface( DestSurface );
+  WorkY := Src.h;
+  case bits of
+    8 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt8( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt8( DestAddr )^;
+              if Pixel2 > 0 then
+              begin
+                if Pixel2 and $E0 > Pixel1 and $E0 then
+                  R := Pixel2 and $E0
+                else
+                  R := Pixel1 and $E0;
+                if Pixel2 and $1C > Pixel1 and $1C then
+                  G := Pixel2 and $1C
+                else
+                  G := Pixel1 and $1C;
+                if Pixel2 and $03 > Pixel1 and $03 then
+                  B := Pixel2 and $03
+                else
+                  B := Pixel1 and $03;
+
+                if R > $E0 then
+                  R := $E0;
+                if G > $1C then
+                  G := $1C;
+                if B > $03 then
+                  B := $03;
+                PUInt8( DestAddr )^ := R or G or B;
+              end
+              else
+                PUInt8( DestAddr )^ := Pixel1;
+            end;
+            inc( SrcAddr );
+            inc( DestAddr );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    15 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt16( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt16( DestAddr )^;
+              if Pixel2 > 0 then
+              begin
+
+                if Pixel2 and $7C00 > Pixel1 and $7C00 then
+                  R := Pixel2 and $7C00
+                else
+                  R := Pixel1 and $7C00;
+                if Pixel2 and $03E0 > Pixel1 and $03E0 then
+                  G := Pixel2 and $03E0
+                else
+                  G := Pixel1 and $03E0;
+                if Pixel2 and $001F > Pixel1 and $001F then
+                  B := Pixel2 and $001F
+                else
+                  B := Pixel1 and $001F;
+
+                PUInt16( DestAddr )^ := R or G or B;
+              end
+              else
+                PUInt16( DestAddr )^ := Pixel1;
+            end;
+            inc( SrcAddr, 2 );
+            inc( DestAddr, 2 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    16 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt16( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt16( DestAddr )^;
+              if Pixel2 > 0 then
+              begin
+
+                if Pixel2 and $F800 > Pixel1 and $F800 then
+                  R := Pixel2 and $F800
+                else
+                  R := Pixel1 and $F800;
+                if Pixel2 and $07E0 > Pixel1 and $07E0 then
+                  G := Pixel2 and $07E0
+                else
+                  G := Pixel1 and $07E0;
+                if Pixel2 and $001F > Pixel1 and $001F then
+                  B := Pixel2 and $001F
+                else
+                  B := Pixel1 and $001F;
+
+                PUInt16( DestAddr )^ := R or G or B;
+              end
+              else
+                PUInt16( DestAddr )^ := Pixel1;
+            end;
+            inc( SrcAddr, 2 );
+            inc( DestAddr, 2 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    24 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt32( SrcAddr )^ and $00FFFFFF;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt32( DestAddr )^ and $00FFFFFF;
+              if Pixel2 > 0 then
+              begin
+
+                if Pixel2 and $FF0000 > Pixel1 and $FF0000 then
+                  R := Pixel2 and $FF0000
+                else
+                  R := Pixel1 and $FF0000;
+                if Pixel2 and $00FF00 > Pixel1 and $00FF00 then
+                  G := Pixel2 and $00FF00
+                else
+                  G := Pixel1 and $00FF00;
+                if Pixel2 and $0000FF > Pixel1 and $0000FF then
+                  B := Pixel2 and $0000FF
+                else
+                  B := Pixel1 and $0000FF;
+
+                PUInt32( DestAddr )^ := PUInt32( DestAddr )^ and $FF000000 or ( R or G or B );
+              end
+              else
+                PUInt32( DestAddr )^ := PUInt32( DestAddr )^ and $FF000000 or Pixel1;
+            end;
+            inc( SrcAddr, 3 );
+            inc( DestAddr, 3 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    32 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt32( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt32( DestAddr )^;
+              if Pixel2 > 0 then
+              begin
+
+                if Pixel2 and $FF0000 > Pixel1 and $FF0000 then
+                  R := Pixel2 and $FF0000
+                else
+                  R := Pixel1 and $FF0000;
+                if Pixel2 and $00FF00 > Pixel1 and $00FF00 then
+                  G := Pixel2 and $00FF00
+                else
+                  G := Pixel1 and $00FF00;
+                if Pixel2 and $0000FF > Pixel1 and $0000FF then
+                  B := Pixel2 and $0000FF
+                else
+                  B := Pixel1 and $0000FF;
+
+                PUInt32( DestAddr )^ := R or G or B;
+              end
+              else
+                PUInt32( DestAddr )^ := Pixel1;
+            end;
+            inc( SrcAddr, 4 );
+            inc( DestAddr, 4 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+  end;
+  SDL_UnlockSurface( SrcSurface );
+  SDL_UnlockSurface( DestSurface );
+end;
+
+
+procedure SDL_LTSurface( SrcSurface : PSDL_Surface; SrcRect : PSDL_Rect;
+  DestSurface : PSDL_Surface; DestRect : PSDL_Rect );
+var
+  R, G, B, Pixel1, Pixel2, TransparentColor : cardinal;
+  Src, Dest    : TSDL_Rect;
+  Diff         : integer;
+  SrcAddr, DestAddr : cardinal;
+  WorkX, WorkY : word;
+  SrcMod, DestMod : cardinal;
+  Bits         : cardinal;
+begin
+  if ( SrcSurface = nil ) or ( DestSurface = nil ) then
+    exit; // Remove this to make it faster
+  if ( SrcSurface.Format.BitsPerPixel <> DestSurface.Format.BitsPerPixel ) then
+    exit; // Remove this to make it faster
+  if SrcRect = nil then
+  begin
+    with Src do
+    begin
+      x := 0;
+      y := 0;
+      w := SrcSurface.w;
+      h := SrcSurface.h;
+    end;
+  end
+  else
+    Src := SrcRect^;
+  if DestRect = nil then
+  begin
+    Dest.x := 0;
+    Dest.y := 0;
+  end
+  else
+    Dest := DestRect^;
+  Dest.w := Src.w;
+  Dest.h := Src.h;
+  with DestSurface.Clip_Rect do
+  begin
+    // Source's right side is greater than the dest.cliprect
+    if Dest.x + Src.w > x + w then
+    begin
+      smallint( Src.w ) := x + w - Dest.x;
+      smallint( Dest.w ) := x + w - Dest.x;
+      if smallint( Dest.w ) < 1 then
+        exit;
+    end;
+    // Source's bottom side is greater than the dest.clip
+    if Dest.y + Src.h > y + h then
+    begin
+      smallint( Src.h ) := y + h - Dest.y;
+      smallint( Dest.h ) := y + h - Dest.y;
+      if smallint( Dest.h ) < 1 then
+        exit;
+    end;
+    // Source's left side is less than the dest.clip
+    if Dest.x < x then
+    begin
+      Diff := x - Dest.x;
+      Src.x := Src.x + Diff;
+      smallint( Src.w ) := smallint( Src.w ) - Diff;
+      Dest.x := x;
+      smallint( Dest.w ) := smallint( Dest.w ) - Diff;
+      if smallint( Dest.w ) < 1 then
+        exit;
+    end;
+    // Source's Top side is less than the dest.clip
+    if Dest.y < y then
+    begin
+      Diff := y - Dest.y;
+      Src.y := Src.y + Diff;
+      smallint( Src.h ) := smallint( Src.h ) - Diff;
+      Dest.y := y;
+      smallint( Dest.h ) := smallint( Dest.h ) - Diff;
+      if smallint( Dest.h ) < 1 then
+        exit;
+    end;
+  end;
+  with SrcSurface^ do
+  begin
+    SrcAddr := cardinal( Pixels ) + UInt32( Src.y ) * Pitch + UInt32( Src.x ) *
+      Format.BytesPerPixel;
+    SrcMod := Pitch - Src.w * Format.BytesPerPixel;
+    TransparentColor := Format.colorkey;
+  end;
+  with DestSurface^ do
+  begin
+    DestAddr := cardinal( Pixels ) + UInt32( Dest.y ) * Pitch + UInt32( Dest.x ) *
+      Format.BytesPerPixel;
+    DestMod := Pitch - Dest.w * Format.BytesPerPixel;
+    Bits := Format.BitsPerPixel;
+  end;
+  SDL_LockSurface( SrcSurface );
+  SDL_LockSurface( DestSurface );
+  WorkY := Src.h;
+  case bits of
+    8 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt8( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt8( DestAddr )^;
+              if Pixel2 > 0 then
+              begin
+                if Pixel2 and $E0 < Pixel1 and $E0 then
+                  R := Pixel2 and $E0
+                else
+                  R := Pixel1 and $E0;
+                if Pixel2 and $1C < Pixel1 and $1C then
+                  G := Pixel2 and $1C
+                else
+                  G := Pixel1 and $1C;
+                if Pixel2 and $03 < Pixel1 and $03 then
+                  B := Pixel2 and $03
+                else
+                  B := Pixel1 and $03;
+
+                if R > $E0 then
+                  R := $E0;
+                if G > $1C then
+                  G := $1C;
+                if B > $03 then
+                  B := $03;
+                PUInt8( DestAddr )^ := R or G or B;
+              end
+              else
+                PUInt8( DestAddr )^ := Pixel1;
+            end;
+            inc( SrcAddr );
+            inc( DestAddr );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    15 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt16( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt16( DestAddr )^;
+              if Pixel2 > 0 then
+              begin
+
+                if Pixel2 and $7C00 < Pixel1 and $7C00 then
+                  R := Pixel2 and $7C00
+                else
+                  R := Pixel1 and $7C00;
+                if Pixel2 and $03E0 < Pixel1 and $03E0 then
+                  G := Pixel2 and $03E0
+                else
+                  G := Pixel1 and $03E0;
+                if Pixel2 and $001F < Pixel1 and $001F then
+                  B := Pixel2 and $001F
+                else
+                  B := Pixel1 and $001F;
+
+                PUInt16( DestAddr )^ := R or G or B;
+              end
+              else
+                PUInt16( DestAddr )^ := Pixel1;
+            end;
+            inc( SrcAddr, 2 );
+            inc( DestAddr, 2 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    16 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt16( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt16( DestAddr )^;
+              if Pixel2 > 0 then
+              begin
+
+                if Pixel2 and $F800 < Pixel1 and $F800 then
+                  R := Pixel2 and $F800
+                else
+                  R := Pixel1 and $F800;
+                if Pixel2 and $07E0 < Pixel1 and $07E0 then
+                  G := Pixel2 and $07E0
+                else
+                  G := Pixel1 and $07E0;
+                if Pixel2 and $001F < Pixel1 and $001F then
+                  B := Pixel2 and $001F
+                else
+                  B := Pixel1 and $001F;
+
+                PUInt16( DestAddr )^ := R or G or B;
+              end
+              else
+                PUInt16( DestAddr )^ := Pixel1;
+            end;
+            inc( SrcAddr, 2 );
+            inc( DestAddr, 2 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    24 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt32( SrcAddr )^ and $00FFFFFF;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt32( DestAddr )^ and $00FFFFFF;
+              if Pixel2 > 0 then
+              begin
+
+                if Pixel2 and $FF0000 < Pixel1 and $FF0000 then
+                  R := Pixel2 and $FF0000
+                else
+                  R := Pixel1 and $FF0000;
+                if Pixel2 and $00FF00 < Pixel1 and $00FF00 then
+                  G := Pixel2 and $00FF00
+                else
+                  G := Pixel1 and $00FF00;
+                if Pixel2 and $0000FF < Pixel1 and $0000FF then
+                  B := Pixel2 and $0000FF
+                else
+                  B := Pixel1 and $0000FF;
+
+                PUInt32( DestAddr )^ := PUInt32( DestAddr )^ and $FF000000 or ( R or G or B );
+              end
+              else
+                PUInt32( DestAddr )^ := PUInt32( DestAddr )^ and $FF000000 or Pixel1;
+            end;
+            inc( SrcAddr, 3 );
+            inc( DestAddr, 3 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+    32 :
+      begin
+        repeat
+          WorkX := Src.w;
+          repeat
+            Pixel1 := PUInt32( SrcAddr )^;
+            if ( Pixel1 <> TransparentColor ) and ( Pixel1 <> 0 ) then
+            begin
+              Pixel2 := PUInt32( DestAddr )^;
+              if Pixel2 > 0 then
+              begin
+
+                if Pixel2 and $FF0000 < Pixel1 and $FF0000 then
+                  R := Pixel2 and $FF0000
+                else
+                  R := Pixel1 and $FF0000;
+                if Pixel2 and $00FF00 < Pixel1 and $00FF00 then
+                  G := Pixel2 and $00FF00
+                else
+                  G := Pixel1 and $00FF00;
+                if Pixel2 and $0000FF < Pixel1 and $0000FF then
+                  B := Pixel2 and $0000FF
+                else
+                  B := Pixel1 and $0000FF;
+
+                PUInt32( DestAddr )^ := R or G or B;
+              end
+              else
+                PUInt32( DestAddr )^ := Pixel1;
+            end;
+            inc( SrcAddr, 4 );
+            inc( DestAddr, 4 );
+            dec( WorkX );
+          until WorkX = 0;
+          inc( SrcAddr, SrcMod );
+          inc( DestAddr, DestMod );
+          dec( WorkY );
+        until WorkY = 0;
+      end;
+  end;
+  SDL_UnlockSurface( SrcSurface );
+  SDL_UnlockSurface( DestSurface );
+end;
+
+// Will clip the x1,x2,y1,x2 params to the ClipRect provided
+
+function SDL_ClipLine( var x1, y1, x2, y2 : Integer; ClipRect : PSDL_Rect ) : boolean;
+var
+  tflag, flag1, flag2 : word;
+  txy, xedge, yedge : Integer;
+  slope        : single;
+
+  function ClipCode( x, y : Integer ) : word;
+  begin
+    Result := 0;
+    if x < ClipRect.x then
+      Result := 1;
+    if x >= ClipRect.w + ClipRect.x then
+      Result := Result or 2;
+    if y < ClipRect.y then
+      Result := Result or 4;
+    if y >= ClipRect.h + ClipRect.y then
+      Result := Result or 8;
+  end;
+
+begin
+  flag1 := ClipCode( x1, y1 );
+  flag2 := ClipCode( x2, y2 );
+  result := true;
+
+  while true do
+  begin
+    if ( flag1 or flag2 ) = 0 then
+      Exit; // all in
+
+    if ( flag1 and flag2 ) <> 0 then
+    begin
+      result := false;
+      Exit; // all out
+    end;
+
+    if flag2 = 0 then
+    begin
+      txy := x1; x1 := x2; x2 := txy;
+      txy := y1; y1 := y2; y2 := txy;
+      tflag := flag1; flag1 := flag2; flag2 := tflag;
+    end;
+
+    if ( flag2 and 3 ) <> 0 then
+    begin
+      if ( flag2 and 1 ) <> 0 then
+        xedge := ClipRect.x
+      else
+        xedge := ClipRect.w + ClipRect.x - 1; // back 1 pixel otherwise we end up in a loop
+
+      slope := ( y2 - y1 ) / ( x2 - x1 );
+      y2 := y1 + Round( slope * ( xedge - x1 ) );
+      x2 := xedge;
+    end
+    else
+    begin
+      if ( flag2 and 4 ) <> 0 then
+        yedge := ClipRect.y
+      else
+        yedge := ClipRect.h + ClipRect.y - 1; // up 1 pixel otherwise we end up in a loop
+
+      slope := ( x2 - x1 ) / ( y2 - y1 );
+      x2 := x1 + Round( slope * ( yedge - y1 ) );
+      y2 := yedge;
+    end;
+
+    flag2 := ClipCode( x2, y2 );
+  end;
+end;
+
+end.
+