A basic raycast engine with not too much additional functionality.

Thanks to: https://code.google.com/p/raycast-dungeon/source/browse/ https://github.com/Mekire/pygame-raycasting-experiment http://www.playfuljs.com/a-first-person-engine-in-265-lines/ http://www.permadi.com/tutorial/raycast/

for the info and great explanations!