exalpha(3alleg4)                 Allegro manual                 exalpha(3alleg4)

       exalpha - Creating and using 32 bit RGBA sprites. Allegro game
       programming library.

       #include <allegro.h>

       Example exalpha

       This program demonstrates how to use the 32 bit RGBA translucency
       functions to store an alpha channel along with a bitmap graphic.  Two
       images are loaded from disk. One will be used for the background and the
       other as a sprite. The example generates an alpha channel for the sprite
       image, composing the 32 bit RGBA bitmap during runtime, and draws it at
       the position of the mouse cursor.

       BITMAP(3alleg4), END_OF_MAIN(3alleg4), SCREEN_H(3alleg4),
       SCREEN_W(3alleg4), allegro_error(3alleg4), allegro_init(3alleg4),
       allegro_message(3alleg4), blit(3alleg4), clear_keybuf(3alleg4),
       create_bitmap(3alleg4), destroy_bitmap(3alleg4),
       draw_trans_sprite(3alleg4), drawing_mode(3alleg4), font(3alleg4),
       getb(3alleg4), getg(3alleg4), getpixel(3alleg4), getr(3alleg4),
       install_keyboard(3alleg4), install_mouse(3alleg4),
       install_timer(3alleg4), keypressed(3alleg4), load_bitmap(3alleg4),
       makecol(3alleg4), mouse_x(3alleg4), mouse_y(3alleg4), putpixel(3alleg4),
       rectfill(3alleg4), replace_filename(3alleg4), screen(3alleg4),
       set_alpha_blender(3alleg4), set_color_conversion(3alleg4),
       set_color_depth(3alleg4), set_gfx_mode(3alleg4),
       set_multiply_blender(3alleg4), set_write_alpha_blender(3alleg4),
       solid_mode(3alleg4), stretch_blit(3alleg4), textprintf_ex(3alleg4)

Allegro                           version 4.4.3                 exalpha(3alleg4)