Crappylos ( w/ Demo) - 2D Line-of-Sight tool for Allegro.
It blacks out areas behind walls which the player/character can't see.
Polygons and line segments are the supported inputs.
H.A.G. utilities - polygon_force_CW( *verts, num_verts); is useful for level editors of games using Simplelos or Monolos.
Allegro4.2, AllegroGL, alleg42.dll [ 1 meg.] - Precompiled libraries for Devc++