2014年3月24日 · 2D games rule and this is the definitive 2D physics engine (but Chipmunk is okay, too... ;) I've had a lot of success with Box2D over the past year and a half on a top-down arcade-style shooter project. It's a bit overkill for my purposes, but very accurate and robust. Download Box2D for free. Box2D is no longer developed on SF.