books.google.com - Simulating physics helps cutting-edge games distinguish themselves by making virtual objects behave as we expect them to in the real world. Physics engines are the software programs that run these simulations. Building an engine is difficult, however. There are a large number of new developers (and hobbyists)...http://books.google.com/books/about/Game_physics_engine_development.html?id=OsJ-8IRkRWgC&utm_source=gb-gplus-shareGame physics engine development
