DUGL
 
Graphics and game programming library

Website: http://dugl.50webs.com
Platforms supported: DOS
Headers to include: DUGL.BI (not yet included with FB, see link below)
Example of usage: see link below
Note: use DUGL 1.13 or newer (see link below), older version have a bug and do crash when used with FB

See forum thread: http://www.freebasic.net/forum/viewtopic.php?t=11046