XNA4.0 2D游戏制作，需要很多碰撞检测来完成游戏的开发，本程序实现了相应的碰撞检测，在2D游戏开发中十分重要-XNA4.0 2D game production, you need a lot of collision detection to complete the development of the game, the program for the collision detection in 2D game development is very important