Swift 2：applyImpulse后停止移动

Question

当一个精灵被施加了如下的冲量，我该如何停止它：

player.physicsBody!.applyImpulse(CGVectorMake(50, 0))

移动是否可以在一段时间内（2秒）逐渐减少？

- Shift72

Answer 1

为了停止物理体的运动，您可以像这样利用“速度”变量：

//this will reset the x, y based velocity to a halt/stop    
player.physicsBody?.velocity = CGVectorMake(0, 0)
//if you would also like to stop any rotation that may be present
player.physicsBody?.angularVelocity = 0

回答你的第二个问题，你应该研究一下'linearDamping'来影响速度和'angularDamping'来影响角速度（旋转）。这些物理体参数允许你在施加冲量后随着时间的推移减慢速度（类似于摩擦力）。

//These values should be set when creating the physicsBody.
//should experiment with these values to get the desired effect.
player.physicsBody?.linearDamping = 1.10
player.physicsBody?.angularDamping = 0.25

- mdhomer