set_color_depth - Man Page

#include <allegro.h>

void set_color_depth(int depth);

Sets the pixel format to be used by subsequent calls to set_gfx_mode()  and create_bitmap(). Valid depths are 8 (the default), 15, 16, 24, and 32  bits. Example:

   set_color_depth(32);
   if (set_gfx_mode(GFX_AUTODETECT, 640, 480, 0, 0) != 0) {
      abort_on_error("Couldn't set a 32 bit color resolution");
   }

Note that the screen color depth won't change until the next successful call to set_gfx_mode().

get_color_depth(3), set_gfx_mode(3), set_color_conversion(3), makecol(3), getr(3), desktop_color_depth(3)

bitmap_color_depth(3), bitmap_mask_color(3), create_bitmap(3), desktop_color_depth(3), destroy_gfx_mode_list(3), ex3d(3), exalpha(3), exblend(3), exconfig(3), exlights(3), expackf(3), exrgbhsv(3), exrotscl(3), exscn3d(3), exswitch(3), extrans2(3), extruec(3), exupdate(3), exxfade(3), exzbuf(3), generate_332_palette(3), generate_optimized_palette(3), get_color_depth(3), get_gfx_mode_list(3), getr(3), getr8(3), getr_depth(3), gfx_mode_select_ex(3), gfx_mode_select_filter(3), load_bitmap(3), load_bitmap_font(3), makecol(3), makecol8(3), makecol_depth(3), palette_color(3), set_color_conversion(3), set_gfx_mode(3).