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-rw-r--r--src/lib/freetype/demo/nehe/UFreeType.pas326
1 files changed, 0 insertions, 326 deletions
diff --git a/src/lib/freetype/demo/nehe/UFreeType.pas b/src/lib/freetype/demo/nehe/UFreeType.pas
deleted file mode 100644
index c1243aae..00000000
--- a/src/lib/freetype/demo/nehe/UFreeType.pas
+++ /dev/null
@@ -1,326 +0,0 @@
-unit UFreeType;
-
-{$IFDEF FPC}
- {$mode delphi}{$H+}
-{$ENDIF}
-
-interface
-
-uses
- FreeType,
- gl,
- glu,
- classes,
- sysutils;
-
-type
- // This holds all of the information related to any
- // freetype font that we want to create.
- TFontData = class
- h: single; ///< Holds the height of the font.
- textures: array of GLuint; ///< Holds the texture id's
- list_base: GLuint; ///< Holds the first display list id
-
- // The init function will create a font of
- // of the height h from the file fname.
- constructor Create(const fname: string; h: cardinal);
-
- // Free all the resources assosiated with the font.
- destructor Destroy(); override;
- end;
-
- TFreeType = class
- public
- // The flagship function of the library - this thing will print
- // out text at window coordinates x,y, using the font ft_font.
- // The current modelview matrix will also be applied to the text.
- class procedure print(ft_font: TFontData; x, y: single; const str: string);
- end;
-
-
-implementation
-
-
-// This function gets the first power of 2 >= the
-// int that we pass it.
-function next_p2 ( a: integer ): integer; inline;
-begin
- Result := 1;
- while (Result < a) do
- Result := Result shl 1;
-end;
-
-type
- PAGLuint = ^AGLuint;
- AGLuint = array[0..High(Word)] of GLuint;
-
-// Create a display list coresponding to the given character.
-procedure make_dlist ( face: FT_Face; ch: byte; list_base: GLuint; tex_base: PAGLuint );
-var
- i, j: integer;
- width, height: integer;
- glyph: FT_Glyph;
- bitmap_glyph: FT_BitmapGlyph;
- bitmap: PFT_Bitmap;
- expanded_data: array of GLubyte;
- x, y: single;
-begin
- // The first thing we do is get FreeType to render our character
- // into a bitmap. This actually requires a couple of FreeType commands:
-
- // Load the Glyph for our character.
- if (FT_Load_Glyph( face, FT_Get_Char_Index( face, ch ), FT_LOAD_DEFAULT ) <> 0) then
- raise Exception.create('FT_Load_Glyph failed');
-
- // Move the face's glyph into a Glyph object.
- if (FT_Get_Glyph( face^.glyph, glyph ) <> 0) then
- raise Exception.create('FT_Get_Glyph failed');
-
- // Convert the glyph to a bitmap.
- FT_Glyph_To_Bitmap( glyph, ft_render_mode_normal, nil, 1 );
- bitmap_glyph := FT_BitmapGlyph(glyph);
-
- // This reference will make accessing the bitmap easier
- bitmap := @bitmap_glyph^.bitmap;
-
- // Use our helper function to get the widths of
- // the bitmap data that we will need in order to create
- // our texture.
- width := next_p2( bitmap.width );
- height := next_p2( bitmap.rows );
-
- // Allocate memory for the texture data.
- SetLength(expanded_data, 2 * width * height);
-
- // Here we fill in the data for the expanded bitmap.
- // Notice that we are using two channel bitmap (one for
- // luminocity and one for alpha), but we assign
- // both luminocity and alpha to the value that we
- // find in the FreeType bitmap.
- // We use the ?: operator so that value which we use
- // will be 0 if we are in the padding zone, and whatever
- // is the the Freetype bitmap otherwise.
- for j := 0 to height-1 do
- begin
- for i := 0 to width-1 do
- begin
- if ((i >= bitmap.width) or (j >= bitmap.rows)) then
- expanded_data[2*(i+j*width)] := 0
- else
- expanded_data[2*(i+j*width)] := byte(bitmap.buffer[i + bitmap.width*j]);
- expanded_data[2*(i+j*width)+1] := expanded_data[2*(i+j*width)];
- end;
- end;
-
-
- // Now we just setup some texture paramaters.
- glBindTexture( GL_TEXTURE_2D, tex_base[integer(ch)]);
- glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
- glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);
-
- // Here we actually create the texture itself, notice
- // that we are using GL_LUMINANCE_ALPHA to indicate that
- // we are using 2 channel data.
- glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA, width, height,
- 0, GL_LUMINANCE_ALPHA, GL_UNSIGNED_BYTE, @expanded_data[0] );
-
- //With the texture created, we don't need to expanded data anymore
- SetLength(expanded_data, 0);
-
- //So now we can create the display list
- glNewList(list_base+ch, GL_COMPILE);
-
- glBindTexture(GL_TEXTURE_2D, tex_base[ch]);
-
- glPushMatrix();
-
- //first we need to move over a little so that
- //the character has the right amount of space
- //between it and the one before it.
- glTranslatef(bitmap_glyph^.left, 0, 0);
-
- //Now we move down a little in the case that the
- //bitmap extends past the bottom of the line
- //(this is only true for characters like 'g' or 'y'.
- glTranslatef(0, bitmap_glyph^.top - bitmap.rows, 0);
-
- //Now we need to account for the fact that many of
- //our textures are filled with empty padding space.
- //We figure what portion of the texture is used by
- //the actual character and store that information in
- //the x and y variables, then when we draw the
- //quad, we will only reference the parts of the texture
- //that we contain the character itself.
- x := bitmap.width / width;
- y := bitmap.rows / height;
-
- //Here we draw the texturemaped quads.
- //The bitmap that we got from FreeType was not
- //oriented quite like we would like it to be,
- //so we need to link the texture to the quad
- //so that the result will be properly aligned.
- glBegin(GL_QUADS);
- glTexCoord2d(0, 0); glVertex2f(0, bitmap.rows);
- glTexCoord2d(0, y); glVertex2f(0, 0);
- glTexCoord2d(x, y); glVertex2f(bitmap.width, 0);
- glTexCoord2d(x, 0); glVertex2f(bitmap.width, bitmap.rows);
- glEnd();
-
- glPopMatrix();
- glTranslatef(face^.glyph^.advance.x shr 6, 0, 0);
-
- //increment the raster position as if we were a bitmap font.
- //(only needed if you want to calculate text length)
- //glBitmap(0,0,0,0,face->glyph->advance.x >> 6,0,NULL);
-
- //Finnish the display list
- glEndList();
-end;
-
-
-constructor TFontData.Create(const fname: string; h: cardinal);
-var
- library_: FT_Library;
- //The object in which Freetype holds information on a given
- //font is called a "face".
- face: FT_Face;
- i: byte;
-begin
- //Allocate some memory to store the texture ids.
- SetLength(textures, 128);
-
- Self.h := h;
-
- //Create and initilize a freetype font library.
- if (FT_Init_FreeType( library_ ) <> 0) then
- raise Exception.create('FT_Init_FreeType failed');
-
- //This is where we load in the font information from the file.
- //Of all the places where the code might die, this is the most likely,
- //as FT_New_Face will die if the font file does not exist or is somehow broken.
- if (FT_New_Face( library_, PChar(fname), 0, face ) <> 0) then
- raise Exception.create('FT_New_Face failed (there is probably a problem with your font file)');
-
- //For some twisted reason, Freetype measures font size
- //in terms of 1/64ths of pixels. Thus, to make a font
- //h pixels high, we need to request a size of h*64.
- //(h shl 6 is just a prettier way of writting h*64)
- FT_Set_Char_Size( face, h shl 6, h shl 6, 96, 96);
-
- //Here we ask opengl to allocate resources for
- //all the textures and displays lists which we
- //are about to create.
- list_base := glGenLists(128);
- glGenTextures( 128, @textures[0] );
-
- //This is where we actually create each of the fonts display lists.
- for i := 0 to 127 do
- make_dlist(face, i, list_base, @textures[0]);
-
- //We don't need the face information now that the display
- //lists have been created, so we free the assosiated resources.
- FT_Done_Face(face);
-
- //Ditto for the library.
- FT_Done_FreeType(library_);
-end;
-
-destructor TFontData.Destroy();
-begin
- glDeleteLists(list_base, 128);
- glDeleteTextures(128, @textures[0]);
- SetLength(textures, 0);
-end;
-
-/// A fairly straight forward function that pushes
-/// a projection matrix that will make object world
-/// coordinates identical to window coordinates.
-procedure pushScreenCoordinateMatrix(); inline;
-var
- viewport: array [0..3] of GLint;
-begin
- glPushAttrib(GL_TRANSFORM_BIT);
- glGetIntegerv(GL_VIEWPORT, @viewport);
- glMatrixMode(GL_PROJECTION);
- glPushMatrix();
- glLoadIdentity();
- gluOrtho2D(viewport[0], viewport[2], viewport[1], viewport[3]);
- glPopAttrib();
-end;
-
-/// Pops the projection matrix without changing the current
-/// MatrixMode.
-procedure pop_projection_matrix(); inline;
-begin
- glPushAttrib(GL_TRANSFORM_BIT);
- glMatrixMode(GL_PROJECTION);
- glPopMatrix();
- glPopAttrib();
-end;
-
-///Much like Nehe's glPrint function, but modified to work
-///with freetype fonts.
-class procedure TFreeType.print(ft_font: TFontData; x, y: single; const str: string);
-var
- font: GLuint;
- h: single;
- i: cardinal;
- lines: TStringList;
- modelview_matrix: array[0..15] of single;
-begin
- // We want a coordinate system where things coresponding to window pixels.
- pushScreenCoordinateMatrix();
-
- font := ft_font.list_base;
- h := ft_font.h / 0.63; //We make the height about 1.5* that of
-
- lines := TStringList.Create();
- ExtractStrings([#13], [], PChar(str), lines);
-
- glPushAttrib(GL_LIST_BIT or GL_CURRENT_BIT or GL_ENABLE_BIT or GL_TRANSFORM_BIT);
- glMatrixMode(GL_MODELVIEW);
- glDisable(GL_LIGHTING);
- glEnable(GL_TEXTURE_2D);
- glDisable(GL_DEPTH_TEST);
- glEnable(GL_BLEND);
- glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
-
- glListBase(font);
-
- glGetFloatv(GL_MODELVIEW_MATRIX, @modelview_matrix);
-
- //This is where the text display actually happens.
- //For each line of text we reset the modelview matrix
- //so that the line's text will start in the correct position.
- //Notice that we need to reset the matrix, rather than just translating
- //down by h. This is because when each character is
- //draw it modifies the current matrix so that the next character
- //will be drawn immediatly after it.
- for i := 0 to lines.Count-1 do
- begin
- glPushMatrix();
- glLoadIdentity();
- glTranslatef(x, y - h*i, 0);
- glMultMatrixf(@modelview_matrix);
-
- // The commented out raster position stuff can be useful if you need to
- // know the length of the text that you are creating.
- // If you decide to use it make sure to also uncomment the glBitmap command
- // in make_dlist().
- //glRasterPos2f(0,0);
- glCallLists(Length(lines[i]), GL_UNSIGNED_BYTE, PChar(lines[i]));
- //float rpos[4];
- //glGetFloatv(GL_CURRENT_RASTER_POSITION ,rpos);
- //float len=x-rpos[0];
-
- glPopMatrix();
- end;
-
- glPopAttrib();
-
- pop_projection_matrix();
-
- lines.Free();
-end;
-
-end.
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