Nmarb/Survive — pull request #2 by jdmarble (2013-11-24 21:51:39+00:00)
Title: Performance improvements.

* Use world coordinates and move the player instead of using screen coordinates and moving everything around the player.
* Use a data structure that can return what (if anything) is at a particular world coordinate location. (not an actual spacial data structure yet)
* Break a lot of stuff in the process.