aboutsummaryrefslogblamecommitdiffstats
path: root/Game/Code/Classes/UImage.pas
blob: bc23bbf5dc7742d3306f35449588ef2473ef4e84 (plain) (tree)
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706












































































































                                                                                                  

                                                            






















                                  

             










































































































































                                                                                                





                                 

                      
                         





































































































































































































































































































































































































































                                                                                                          



                                                            
























































                                                                                                   
 
     
unit UImage;

interface

{$IFDEF FPC}
  {$MODE Delphi}
{$ENDIF}

{$I ../switches.inc}

uses
  SDL;

{$DEFINE HavePNG}
{$DEFINE HaveBMP}
{$DEFINE HaveJPG}

const
  PixelFmt_RGBA: TSDL_Pixelformat = (
    palette:      nil;
    BitsPerPixel:  32;
    BytesPerPixel:  4;
    Rloss:          0;
    Gloss:          0;
    Bloss:          0;
    Aloss:          0;
    Rshift:         0;
    Gshift:         8;
    Bshift:        16;
    Ashift:        24;
    Rmask:  $000000ff;
    Gmask:  $0000ff00;
    Bmask:  $00ff0000;
    Amask:  $ff000000;
    ColorKey:       0;
    Alpha:        255
  );

  PixelFmt_RGB: TSDL_Pixelformat = (
    palette:      nil;
    BitsPerPixel:  24;
    BytesPerPixel:  3;
    Rloss:          0;
    Gloss:          0;
    Bloss:          0;
    Aloss:          0;
    Rshift:         0;
    Gshift:         8;
    Bshift:        16;
    Ashift:         0;
    Rmask:  $000000ff;
    Gmask:  $0000ff00;
    Bmask:  $00ff0000;
    Amask:  $00000000;
    ColorKey:       0;
    Alpha:        255
  );

  PixelFmt_BGRA: TSDL_Pixelformat = (
    palette:      nil;
    BitsPerPixel:  32;
    BytesPerPixel:  4;
    Rloss:          0;
    Gloss:          0;
    Bloss:          0;
    Aloss:          0;
    Rshift:        16;
    Gshift:         8;
    Bshift:         0;
    Ashift:        24;
    Rmask:  $00ff0000;
    Gmask:  $0000ff00;
    Bmask:  $000000ff;
    Amask:  $ff000000;
    ColorKey:       0;
    Alpha:        255
  );

  PixelFmt_BGR: TSDL_Pixelformat = (
    palette:      nil;
    BitsPerPixel:  24;
    BytesPerPixel:  3;
    Rloss:          0;
    Gloss:          0;
    Bloss:          0;
    Aloss:          0;
    Rshift:        16;
    Gshift:         8;
    Bshift:         0;
    Ashift:         0;
    Rmask:  $00ff0000;
    Gmask:  $0000ff00;
    Bmask:  $000000ff;
    Amask:  $00000000;
    ColorKey:       0;
    Alpha:        255
  );


{$IFDEF HavePNG}
function WritePNGImage(const FileName: string; Surface: PSDL_Surface): boolean;
{$ENDIF}
{$IFDEF HaveBMP}
function WriteBMPImage(const FileName: string; Surface: PSDL_Surface): boolean;
{$ENDIF}
{$IFDEF HaveJPG}
function WriteJPGImage(const FileName: string; Surface: PSDL_Surface; Quality: integer): boolean;
{$ENDIF}

function LoadImage(const Identifier: string): PSDL_Surface;

implementation

uses
  SysUtils,
  Classes,
  {$IFDEF MSWINDOWS}
  Windows,
  {$ENDIF}
  {$IFDEF HaveJPG}
    {$IFDEF Delphi}
    Graphics,
    jpeg,
    {$ELSE}
    jpeglib,
    jerror,
    jcparam,
    jdatadst, jcapimin, jcapistd,
    {$ENDIF}
  {$ENDIF}
  {$IFDEF HavePNG}
  png,
  {$ENDIF}
  zlib,
  sdl_image,
  UCommon,
  ULog;

function IsRGBSurface(pixelFmt: PSDL_PixelFormat): boolean;
begin
  Result := (pixelFmt.BitsPerPixel = 24) and
            (pixelFmt.RMask = $0000FF)   and
            (pixelFmt.GMask = $00FF00)   and
            (pixelFmt.BMask = $FF0000);
end;

function IsRGBASurface(pixelFmt: PSDL_PixelFormat): boolean;
begin
  Result := (pixelFmt.BitsPerPixel = 32) and
            (pixelFmt.RMask = $000000FF) and
            (pixelFmt.GMask = $0000FF00) and
            (pixelFmt.BMask = $00FF0000) and
            (pixelFmt.AMask = $FF000000);
end;

function IsBGRSurface(pixelFmt: PSDL_PixelFormat): boolean;
begin
  Result := (pixelFmt.BitsPerPixel = 24) and
            (pixelFmt.BMask = $0000FF)   and
            (pixelFmt.GMask = $00FF00)   and
            (pixelFmt.RMask = $FF0000);
end;

function IsBGRASurface(pixelFmt: PSDL_PixelFormat): boolean;
begin
  Result := (pixelFmt.BitsPerPixel = 32) and
            (pixelFmt.BMask = $000000FF) and
            (pixelFmt.GMask = $0000FF00) and
            (pixelFmt.RMask = $00FF0000) and
            (pixelFmt.AMask = $FF000000);
end;

// Converts alpha-formats to BGRA, non-alpha to BGR, and leaves BGR(A) as is
// sets converted to true if the surface needed to be converted
function ConvertToBGR_BGRASurface(Surface: PSDL_Surface; out Converted: boolean): PSDL_Surface;
var
  pixelFmt: PSDL_PixelFormat;
begin
  pixelFmt := Surface.format;
  if (IsBGRSurface(pixelFmt) or IsBGRASurface(pixelFmt)) then
  begin
    Converted := false;
    Result := Surface;
  end
  else
  begin
    // invalid format -> needs conversion
    if (pixelFmt.AMask <> 0) then
      Result := SDL_ConvertSurface(Surface, @PixelFmt_BGRA, SDL_SWSURFACE)
    else
      Result := SDL_ConvertSurface(Surface, @PixelFmt_BGR, SDL_SWSURFACE);
    Converted := true;
  end;
end;

// Converts alpha-formats to RGBA, non-alpha to RGB, and leaves RGB(A) as is
// sets converted to true if the surface needed to be converted
function ConvertToRGB_RGBASurface(Surface: PSDL_Surface; out Converted: boolean): PSDL_Surface;
var
  pixelFmt: PSDL_PixelFormat;
begin
  pixelFmt := Surface.format;
  if (IsRGBSurface(pixelFmt) or IsRGBASurface(pixelFmt)) then
  begin
    Converted := false;
    Result := Surface;
  end
  else
  begin
    // invalid format -> needs conversion
    if (pixelFmt.AMask <> 0) then
      Result := SDL_ConvertSurface(Surface, @PixelFmt_RGBA, SDL_SWSURFACE)
    else
      Result := SDL_ConvertSurface(Surface, @PixelFmt_RGB, SDL_SWSURFACE);
    Converted := true;
  end;
end;

(***************************
 * PNG section
 *****************************)

{$IFDEF HavePNG}

// delphi does not support setjmp()/longjmp() -> define our own error-handler
procedure user_error_fn(png_ptr: png_structp; error_msg: png_const_charp); cdecl;
begin
  raise Exception.Create(error_msg);
end;

procedure user_read_data(png_ptr: png_structp; data: png_bytep; length: png_size_t); cdecl;
var
  inFile: TFileStream;
begin
  inFile := TFileStream(png_get_io_ptr(png_ptr));
  inFile.Read(data^, length);
end;

procedure user_write_data(png_ptr: png_structp; data: png_bytep; length: png_size_t); cdecl;
var
  outFile: TFileStream;
begin
  outFile := TFileStream(png_get_io_ptr(png_ptr));
  outFile.Write(data^, length);
end;

procedure user_flush_data(png_ptr: png_structp); cdecl;
//var
//  outFile: TFileStream;
begin
  // binary files are flushed automatically, Flush() works with Text-files only
  //outFile := TFileStream(png_get_io_ptr(png_ptr));
  //outFile.Flush();
end;

procedure DateTimeToPngTime(time: TDateTime; var pngTime: png_time);
var
  year, month, day: word;
  hour, minute, second, msecond: word;
begin
  DecodeDate(time, year, month, day);
  pngTime.year  := year;
  pngTime.month := month;
  pngTime.day   := day;
  DecodeTime(time, hour, minute, second, msecond);
  pngTime.hour   := hour;
  pngTime.minute := minute;
  pngTime.second := second;
end;

(*
 * ImageData must be in RGB-format
 *)
function WritePNGImage(const FileName: string; Surface: PSDL_Surface): boolean;
var
  png_ptr:   png_structp;
  info_ptr:  png_infop;
  pngFile:   TFileStream;
  row:       integer;
  rowData:   array of png_bytep;
//  rowStride: integer;
  converted: boolean;
  colorType: integer;
//  time:      png_time;
begin
  Result := false;

  // open file for writing
  try
    pngFile := TFileStream.Create(FileName, fmCreate);
  except
    Log.LogError('Could not open file: "' + FileName + '"', 'WritePngImage');
    Exit;
  end;

  // only 24bit (RGB) or 32bit (RGBA) data is supported, so convert to it
  Surface := ConvertToRGB_RGBASurface(Surface, converted);

  png_ptr := nil;

  try
    // initialize png (and enable a user-defined error-handler that throws an exception on error)
    png_ptr := png_create_write_struct(PNG_LIBPNG_VER_STRING, nil, @user_error_fn, nil);
    // the error-handler is called if png_create_write_struct() fails, so png_ptr should always be <> nil
    if (png_ptr = nil) then
    begin
      Log.LogError('png_create_write_struct() failed', 'WritePngImage');
      if (converted) then
        SDL_FreeSurface(Surface);
      Exit;
    end;

    info_ptr := png_create_info_struct(png_ptr);

    if (Surface^.format^.BitsPerPixel = 24) then
      colorType := PNG_COLOR_TYPE_RGB
    else
      colorType := PNG_COLOR_TYPE_RGBA;

    // define write IO-functions (POSIX-style FILE-pointers are not available in Delphi)
    png_set_write_fn(png_ptr, pngFile, @user_write_data, @user_flush_data);
    png_set_IHDR(
      png_ptr, info_ptr,
      Surface.w, Surface.h,
      8,
      colorType,
      PNG_INTERLACE_NONE,
      PNG_COMPRESSION_TYPE_DEFAULT,
      PNG_FILTER_TYPE_DEFAULT
    );

    // TODO: do we need the modification time?
    //DateTimeToPngTime(Now, time);
    //png_set_tIME(png_ptr, info_ptr, @time);

    if (SDL_MUSTLOCK(Surface)) then
      SDL_LockSurface(Surface);

    // setup data
    SetLength(rowData, Surface.h);
    for row := 0 to Surface.h-1 do
    begin
      // set rowData-elements to beginning of each image row
      // Note: the byte-count of a row is pitch (which is not width*bitsPerPixel if the image is aligned)
      rowData[row] := @PChar(Surface.pixels)[(Surface.h-row-1) * Surface.pitch];
    end;

    if (SDL_MUSTLOCK(Surface)) then
      SDL_UnlockSurface(Surface);

    png_write_info(png_ptr, info_ptr);
    png_write_image(png_ptr, png_bytepp(rowData));
    png_write_end(png_ptr, nil);

    Result := true;
  except on E: Exception do
    Log.LogError(E.message, 'WritePngImage');
  end;

  // free row-data
  SetLength(rowData, 0);

  // free png-resources
  if (png_ptr <> nil) then
    png_destroy_write_struct(@png_ptr, nil);

  if (converted) then
    SDL_FreeSurface(Surface);

  // close file
  pngFile.Free;
end;

{$ENDIF}

(***************************
 * BMP section
 *****************************)

{$IFDEF HaveBMP}

{$IFNDEF MSWINDOWS}
const
  (* constants for the biCompression field *)
  BI_RGB       = 0;
  BI_RLE8      = 1;
  BI_RLE4      = 2;
  BI_BITFIELDS = 3;
  BI_JPEG      = 4;
  BI_PNG       = 5;

type
  BITMAPINFOHEADER = record
    biSize:          longword;
    biWidth:         longint;
    biHeight:        longint;
    biPlanes:        word;
    biBitCount:      word;
    biCompression:   longword;
    biSizeImage:     longword;
    biXPelsPerMeter: longint;
    biYPelsPerMeter: longint;
    biClrUsed:       longword;
    biClrImportant:  longword;
  end;
  LPBITMAPINFOHEADER = ^BITMAPINFOHEADER;
  TBITMAPINFOHEADER  = BITMAPINFOHEADER;
  PBITMAPINFOHEADER  = ^BITMAPINFOHEADER;

  RGBTRIPLE = record
    rgbtBlue:  byte;
    rgbtGreen: byte;
    rgbtRed:   byte;
  end;
  tagRGBTRIPLE = RGBTRIPLE;
  TRGBTRIPLE = RGBTRIPLE;
  PRGBTRIPLE = ^RGBTRIPLE;

  RGBQUAD = record
    rgbBlue:     byte;
    rgbGreen:    byte;
    rgbRed:      byte;
    rgbReserved: byte;
  end;
  tagRGBQUAD = RGBQUAD;
  TRGBQUAD = RGBQUAD;
  PRGBQUAD = ^RGBQUAD;

  BITMAPINFO = record
    bmiHeader: BITMAPINFOHEADER;
    bmiColors: array[0..0] of RGBQUAD;
  end;
  LPBITMAPINFO = ^BITMAPINFO;
  PBITMAPINFO = ^BITMAPINFO;
  TBITMAPINFO = BITMAPINFO;

  {$PACKRECORDS 2}
  BITMAPFILEHEADER = record
    bfType:      word;
    bfSize:      longword;
    bfReserved1: word;
    bfReserved2: word;
    bfOffBits:   longword;
  end;
  {$PACKRECORDS DEFAULT}
{$ENDIF}

(*
 * ImageData must be in BGR-format
 *)
function WriteBMPImage(const FileName: string; Surface: PSDL_Surface): boolean;
var
  bmpFile:    TFileStream;
  FileInfo:   BITMAPINFOHEADER;
  FileHeader: BITMAPFILEHEADER;
  Converted:  boolean;
  Row:        integer;
  RowSize:    integer;
begin
  Result := false;

  // open file for writing
  try
    bmpFile := TFileStream.Create(FileName, fmCreate);
  except
    Log.LogError('Could not open file: "' + FileName + '"', 'WriteBMPImage');
    Exit;
  end;

  // only 24bit (BGR) or 32bit (BGRA) data is supported, so convert to it
  Surface := ConvertToBGR_BGRASurface(Surface, Converted);

  // aligned (4-byte) row-size in bytes
  RowSize := ((Surface.w * Surface.format.BytesPerPixel + 3) div 4) * 4;

  // initialize bitmap info
  FillChar(FileInfo, SizeOf(BITMAPINFOHEADER), 0);
  with FileInfo do
  begin
    biSize := SizeOf(BITMAPINFOHEADER);
    biWidth := Surface.w;
    biHeight := Surface.h;
    biPlanes := 1;
    biBitCount := Surface^.format^.BitsPerPixel;
    biCompression := BI_RGB;
    biSizeImage := RowSize * Surface.h;
  end;

  // initialize header-data
  FillChar(FileHeader, SizeOf(BITMAPFILEHEADER), 0);
  with FileHeader do
  begin
    bfType := $4D42; // = 'BM'
    bfOffBits := SizeOf(BITMAPFILEHEADER) + SizeOf(BITMAPINFOHEADER);
    bfSize := bfOffBits + FileInfo.biSizeImage;
  end;

  // and move the whole stuff into the file ;-)
  try
    // write headers
    bmpFile.Write(FileHeader, SizeOf(BITMAPFILEHEADER));
    bmpFile.Write(FileInfo,   SizeOf(BITMAPINFOHEADER));

    // write image-data

    if (SDL_MUSTLOCK(Surface)) then
      SDL_LockSurface(Surface);

    // BMP needs 4-byte alignment
    if (Surface.pitch mod 4 = 0) then
    begin
      // aligned correctly -> write whole image at once
      bmpFile.Write(Surface.pixels^, FileInfo.biSizeImage);
    end
    else
    begin
      // misaligned -> write each line separately
      // Note: for the last line unassigned memory (> last Surface.pixels element)
      //   will be copied to the padding area (last bytes of a row),
      //   but we do not care because the content of padding data is ignored anyhow.
      for Row := 0 to Surface.h do
        bmpFile.Write(PChar(Surface.pixels)[Row * Surface.pitch], RowSize);
    end;

    if (SDL_MUSTLOCK(Surface)) then
      SDL_UnlockSurface(Surface);

    Result := true;
  finally
    Log.LogError('Could not write file: "' + FileName + '"', 'WriteBMPImage');
  end;

  if (Converted) then
    SDL_FreeSurface(Surface);

  // close file
  bmpFile.Free;
end;

{$ENDIF}

(***************************
 * JPG section
 *****************************)

{$IFDEF HaveJPG}

function WriteJPGImage(const FileName: string; Surface: PSDL_Surface; Quality: integer): boolean;
var
  {$IFDEF Delphi}
  Bitmap:    TBitmap;
  BitmapInfo: TBitmapInfo;
  Jpeg:      TJpegImage;
  row:       integer;
  {$ELSE}
  cinfo:     jpeg_compress_struct;
  jerr :     jpeg_error_mgr;
  jpgFile:   TFileStream;
  rowPtr:    array[0..0] of JSAMPROW;
  {$ENDIF}
  converted: boolean;
begin
  Result := false;

  {$IFDEF Delphi}
    // only 24bit (BGR) data is supported, so convert to it
    if (IsBGRSurface(Surface.format)) then
      converted := false
    else
    begin
      Surface := SDL_ConvertSurface(Surface, @PixelFmt_BGR, SDL_SWSURFACE);
      converted := true;
    end;

    // create and setup bitmap
    Bitmap := TBitmap.Create;
    Bitmap.PixelFormat := pf24bit;
    Bitmap.Width  := Surface.w;
    Bitmap.Height := Surface.h;

    // setup bitmap info on source image (Surface parameter)
    ZeroMemory(@BitmapInfo, SizeOf(BitmapInfo));
    with BitmapInfo.bmiHeader do
    begin
      biSize := SizeOf(BITMAPINFOHEADER);
      biWidth  := Surface.w;
      biHeight := Surface.h;
      biPlanes := 1;
      biBitCount := 24;
      biCompression := BI_RGB;
    end;

    if (SDL_MUSTLOCK(Surface)) then
      SDL_LockSurface(Surface);

    // use fast Win32-API functions to copy data instead of Bitmap.Canvas.Pixels
    if (Surface.pitch mod 4 = 0) then
    begin
      // if the image is aligned (to a 4-byte boundary) -> copy all data at once
      // Note: surfaces created with SDL (e.g. with SDL_ConvertSurface) are aligned
      SetDIBits(0, Bitmap.Handle, 0, Bitmap.Height, Surface.pixels, BitmapInfo, DIB_RGB_COLORS);
    end
    else
    begin
      // wrong alignment -> copy each line separately.
      // Note: for the last line unassigned memory (> last Surface.pixels element)
      //   will be copied to the padding area (last bytes of a row),
      //   but we do not care because the content of padding data is ignored anyhow.
      for row := 0 to Surface.h do
      begin
        SetDIBits(0, Bitmap.Handle, row, 1, @PChar(Surface.pixels)[row * Surface.pitch],
          BitmapInfo, DIB_RGB_COLORS);
      end;
    end;

    if (SDL_MUSTLOCK(Surface)) then
      SDL_UnlockSurface(Surface);

    // assign Bitmap to JPEG and store the latter
    Jpeg := TJPEGImage.Create;
    Jpeg.Assign(Bitmap);
    Bitmap.Free;
    Jpeg.CompressionQuality := Quality;
    try
      // compress image (don't forget this line, otherwise it won't be compressed)
      Jpeg.Compress();
      Jpeg.SaveToFile(FileName);
    except
      Log.LogError('Could not save file: "' + FileName + '"', 'WriteJPGImage');
      Exit;
    end;
    Jpeg.Free;
  {$ELSE}
    // based on example.pas in FPC's packages/base/pasjpeg directory

    // only 24bit (RGB) data is supported, so convert to it
    if (IsRGBSurface(Surface.format)) then
      converted := false
    else
    begin
      Surface := SDL_ConvertSurface(Surface, @PixelFmt_RGB, SDL_SWSURFACE);
      converted := true;
    end;

    // allocate and initialize JPEG compression object
    cinfo.err := jpeg_std_error(jerr);
    // msg_level that will be displayed. (Nomssi)
    //jerr.trace_level := 3;
    // initialize the JPEG compression object
    jpeg_create_compress(@cinfo);

    // open file for writing
    try
      jpgFile := TFileStream.Create(FileName, fmCreate);
    except
      Log.LogError('Could not open file: "' + FileName + '"', 'WriteJPGImage');
      Exit;
    end;

    // specify data destination
    jpeg_stdio_dest(@cinfo, @jpgFile);

    // set parameters for compression
    cinfo.image_width := Surface.w;
    cinfo.image_height := Surface.h;
    cinfo.in_color_space := JCS_RGB;
    cinfo.input_components := 3;
    cinfo.data_precision := 8;

    // set default compression parameters
    jpeg_set_defaults(@cinfo);
    jpeg_set_quality(@cinfo, quality, true);

    // start compressor
    jpeg_start_compress(@cinfo, true);

    if (SDL_MUSTLOCK(Surface)) then
      SDL_LockSurface(Surface);

    while (cinfo.next_scanline < cinfo.image_height) do
    begin
      // Note: the byte-count of a row is pitch (which is not width*bitsPerPixel if the image is aligned)
      rowPtr[0] := JSAMPROW(@PChar(Surface.pixels)[(Surface.h-cinfo.next_scanline-1) * Surface.pitch]);
      jpeg_write_scanlines(@cinfo, JSAMPARRAY(@rowPtr), 1);
    end;

    if (SDL_MUSTLOCK(Surface)) then
      SDL_UnlockSurface(Surface);

    // finish compression
    jpeg_finish_compress(@cinfo);
    // close the output file
    jpgFile.Free;

    // release JPEG compression object
    jpeg_destroy_compress(@cinfo);
  {$ENDIF}

  if (converted) then
    SDL_FreeSurface(Surface);

  Result := true;
end;

{$ENDIF}

(*
 * Loads an image from the given file or resource
 *)
function LoadImage(const Identifier: string): PSDL_Surface;
var
  TexRWops:  PSDL_RWops;
  TexStream: TStream;
  FileName: string;
begin
  Result   := nil;
  TexRWops := nil;

  if Identifier = '' then
    exit;
    
  //Log.LogStatus( Identifier, 'LoadImage' );

  FileName := Identifier;

  if (FileExistsInsensitive(FileName)) then
  begin
    // load from file
    //Log.LogStatus( 'Is File ( Loading : '+FileName+')', '  LoadImage' );
    try
      Result := IMG_Load(PChar(FileName));
      //Log.LogStatus( '       '+inttostr( integer( Result ) ), '  LoadImage' );
    except
      Log.LogError('Could not load from file "'+FileName+'"', 'TTextureUnit.LoadImage');
      Exit;
    end;
  end
  else
  begin
    //Log.LogStatus( 'IS Resource, because file does not exist.('+Identifier+')', '  LoadImage' );

    TexStream := GetResourceStream(Identifier, 'TEX');
    if (not assigned(TexStream)) then
    begin
      Log.LogError( 'Invalid file or resource "'+ Identifier+'"', 'TTextureUnit.LoadImage');
      Exit;
    end;

    TexRWops := RWopsFromStream(TexStream);
    if (TexRWops = nil) then
    begin
      Log.LogError( 'Could not assign resource "'+Identifier+'"', 'TTextureUnit.LoadImage');
      TexStream.Free();
      Exit;
    end;

    //Log.LogStatus( 'resource Assigned....' , Identifier);
    try
      Result := IMG_Load_RW(TexRWops, 0);
    except
      Log.LogError( 'Could not read resource "'+Identifier+'"', 'TTextureUnit.LoadImage');
    end;

    SDL_FreeRW(TexRWops);
    TexStream.Free();
  end;
end;

end.