Allegro 'libgif' animation library

From 2001, an Allegro library for loading GIF animations as a BITMAP pointer that automatically animates (due to an installed timer callback routine). Simplifies animation to the point of:

BITMAP *bmp = load_gif(filename, 0);
...
draw_sprite(screen, bmp, x, y); /* BITMAP automatically changes with time. */

(Source)

The original code is by Paul Bartrum. My changes are in the public domain. Thanks to Marco Antônio for helping me find my own code...