getr_depth man page

getr_depth, getg_depth, getb_depth, geta_depth — Extract a color component from a color in a specified pixel format. Allegro game programming library.


#include <allegro.h>

int getr_depth(int color_depth, int c);

int getg_depth(int color_depth, int c);

int getb_depth(int color_depth, int c);

int geta_depth(int color_depth, int c);


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(3), getr8(3), geta32(3), makecol(3), set_color_depth(3), exlights(3)

Referenced By

exlights(3), getr(3), getr8(3).

The man pages geta_depth(3), getb_depth(3) and getg_depth(3) are aliases of getr_depth(3).

version 4.4.2 Allegro manual