- geta — Extract a color component from the current pixel format.
- geta32 — Extract the alpha component form a 32-bit pixel format color.
- geta_depth — Extract a color component from a color in a specified pixel format.
- getb — Extract a color component from the current pixel format.
- getb15 — Extract a color component from the specified pixel format.
- getb16 — Extract a color component from the specified pixel format.
- getb24 — Extract a color component from the specified pixel format.
- getb32 — Extract a color component from the specified pixel format.
- getb8 — Extract a color component from the specified pixel format.
- getb_depth — Extract a color component from a color in a specified pixel format.
- getg — Extract a color component from the current pixel format.
- getg15 — Extract a color component from the specified pixel format.
- getg16 — Extract a color component from the specified pixel format.
- getg24 — Extract a color component from the specified pixel format.
- getg32 — Extract a color component from the specified pixel format.
- getg8 — Extract a color component from the specified pixel format.
- getg_depth — Extract a color component from a color in a specified pixel format.
- getr — Extract a color component from the current pixel format.
- getr15 — Extract a color component from the specified pixel format.
- getr16 — Extract a color component from the specified pixel format.
- getr24 — Extract a color component from the specified pixel format.
- getr32 — Extract a color component from the specified pixel format.
- getr8 — Extract a color component from the specified pixel format.
- getr_depth — Extract a color component from a color in a specified pixel format.
- makeacol — Converts RGBA colors into display dependent pixel formats.
- makeacol32 — Converts an RGBA color into a 32-bit display pixel format.
- makeacol_depth — Converts RGBA colors into display dependent pixel formats.
- makecol — Converts an RGB value into the current pixel format.
- makecol15 — Converts an RGB value into a display dependent pixel format.
- makecol15_dither — Calculates a dithered 15 or 16-bit RGB value.
- makecol16 — Converts an RGB value into a display dependent pixel format.
- makecol16_dither — Calculates a dithered 15 or 16-bit RGB value.
- makecol24 — Converts an RGB value into a display dependent pixel format.
- makecol32 — Converts an RGB value into a display dependent pixel format.
- makecol8 — Converts an RGB value into a display dependent pixel format.
- makecol_depth — Converts an RGB value into the specified pixel format.
- MASK_COLOR_15 — Constant representing the mask value in sprites.
- MASK_COLOR_16 — Constant representing the mask value in sprites.
- MASK_COLOR_24 — Constant representing the mask value in sprites.
- MASK_COLOR_32 — Constant representing the mask value in sprites.
- MASK_COLOR_8 — Constant representing the mask value in sprites.
- palette_color — Maps palette indexes into the current pixel format colors.
In a truecolor video mode the red, green, and blue components for each pixel 
are packed directly into the color value, rather than using a palette lookup 
table. In a 15-bit mode there are 5 bits for each color, in 16-bit modes 
there are 5 bits each of red and blue and six bits of green, and both 24 and 
32-bit modes use 8 bits for each color (the 32-bit pixels simply have an 
extra padding byte to align the data nicely). The layout of these components 
can vary depending on your hardware, but will generally either be RGB or 
BGR. Since the layout is not known until you select the video mode you will 
be using, you must call set_gfx_mode() before using any of the following 
routines!
   These functions convert colors from a hardware independent form (red, 
   green, and blue values ranging 0-255) into various display dependent 
   pixel formats. Converting to 15, 16, 24, or 32-bit formats only takes a 
   few shifts, so it is fairly efficient. Converting to an 8-bit color 
   involves searching the palette to find the closest match, which is quite 
   slow unless you have set up an RGB mapping table (see below). Example:
      /* 16 bit color version of green. */
      int green_color = makecol16(0, 255, 0);
Return value:
   Returns the requested RGB triplet in the specified color depth.
See also:
makeacol32,
makecol,
makecol_depth,
makecol15_dither,
rgb_map,
bestfit_color,
set_color_depth.
Examples using this:
exrgbhsv.
   Converts an RGBA color into a 32-bit display pixel format, which includes 
   an alpha (transparency) value. There are no versions of this routine for 
   other color depths, because only the 32-bit format has enough room to 
   store a proper alpha channel. You should only use RGBA format colors as 
   the input to draw_trans_sprite() or draw_trans_rle_sprite() after calling 
   set_alpha_blender(), rather than drawing them directly to the screen.
See also:
makeacol,
set_alpha_blender,
set_write_alpha_blender.
   Converts colors from a hardware independent format (red, green, and blue 
   values ranging 0-255) to the pixel format required by the current video 
   mode, calling the preceding 8, 15, 16, 24, or 32-bit makecol functions as 
   appropriate. Example:
      /* Regardless of color depth, this will look green. */
      int green_color = makecol(0, 255, 0);
Return value:
   Returns the requested RGB triplet in the current color depth.
See also:
makeacol,
makecol8,
makecol_depth,
makecol15_dither,
rgb_map,
set_color_depth.
Examples using this:
Available Allegro examples.
   Converts colors from a hardware independent format (red, green, and blue 
   values ranging 0-255) to the pixel format required by the specified color 
   depth. Example:
      /* Compose the green color for 15 bit color depth. */
      int green_15bit = makecol_depth(15, 0, 255, 0);
Return value:
   Returns the requested RGB triplet in the specified color depth.
See also:
makeacol,
makecol,
makecol8,
makecol15_dither,
rgb_map,
set_color_depth.
int makeacol(int r, int g, int b, int a); 
   Convert RGBA colors into display dependent pixel formats. In anything 
   less than a 32-bit mode, these are the same as calling makecol() or 
   makecol_depth(), but by using these routines it is possible to create 
   32-bit color values that contain a true 8 bit alpha channel along with 
   the red, green, and blue components. You should only use RGBA format 
   colors as the input to draw_trans_sprite() or draw_trans_rle_sprite() 
   after calling set_alpha_blender(), rather than drawing them directly to 
   the screen.
Return value:
   Returns the requested RGBA quadruplet.
See also:
makecol,
makecol_depth,
set_alpha_blender,
set_write_alpha_blender.
   Given both a color value and a pixel coordinate, calculate a dithered 15 
   or 16-bit RGB value. This can produce better results when reducing images 
   from truecolor to hicolor. In addition to calling these functions 
   directly, hicolor dithering can be automatically enabled when loading 
   graphics by calling the set_color_conversion() function, for example 
   set_color_conversion(COLORCONV_REDUCE_TRUE_TO_HI | COLORCONV_DITHER).
   
   Example:
      int pixel1, pixel2;
      /* The following two color values MAY be different. */
      pixel1 = makecol16_dither(255, 192, 64, 0, 0);
      pixel2 = makecol16_dither(255, 192, 64, 1, 0);
Return value:
   Returns the RGB value dithered for the specified coordinate.
See also:
makecol,
makecol8,
set_color_conversion.
   Given a color in a display dependent format, these functions extract one 
   of the red, green, or blue components (ranging 0-255). Example:
      int r, g, b, color_value;
      color_value = _getpixel15(screen, 100, 100);
      r = getr15(color_value);
      g = getg15(color_value);
      b = getb15(color_value);
See also:
geta32,
getr,
getr_depth,
makecol,
set_color_depth.
   Given a color in a 32-bit pixel format, this function extracts the alpha 
   component (ranging 0-255).
See also:
getr8.
   Given a color in the format being used by the current video mode, these 
   functions extract one of the red, green, blue, or alpha components 
   (ranging 0-255), calling the preceding 8, 15, 16, 24, or 32-bit get 
   functions as appropriate. The alpha part is only meaningful for 32-bit 
   pixels. Example:
      int r, g, b, color_value;
      color_value = getpixel(screen, 100, 100);
      r = getr(color_value);
      g = getg(color_value);
      b = getb(color_value);
See also:
getr8,
getr_depth,
makecol,
set_color_depth.
Examples using this:
exalpha.
   Given a color in the format being used by the specified color depth, 
   these functions extract one of the red, green, blue, or alpha components 
   (ranging 0-255). The alpha part is only meaningful for 32-bit pixels.
   Example:
      int r, g, b, color_value, bpp;
      bpp = bitmap_color_depth(bitmap);
      color_value = getpixel(bitmap, 100, 100);
      r = getr_depth(bpp, color_value);
      g = getg_depth(bpp, color_value);
      b = getb_depth(bpp, color_value);
      
See also:
getr,
getr8,
geta32,
makecol,
set_color_depth.
Examples using this:
exlights.
   Table mapping palette index colors (0-255) into whatever pixel format is 
   being used by the current display mode. In a 256-color mode this just 
   maps onto the array index. In truecolor modes it looks up the specified 
   entry in the current palette, and converts that RGB value into the 
   appropriate packed pixel format. Example:
      set_color_depth(32);
      ...
      set_palette(desktop_palette);
      /* Put a pixel with the color 2 (green) of the palette */
      putpixel(screen, 100, 100, palette_color[2]);
See also:
set_palette,
makecol,
set_color_depth.
Examples using this:
Available Allegro examples.
   Constants representing the colors used to mask transparent sprite pixels 
   for each color depth. In 256-color resolutions this is zero, and in 
   truecolor modes it is bright pink (maximum red and blue, zero green).
See also:
bitmap_mask_color,
makecol,
draw_sprite,
masked_blit.