Impact is a powerful and flexible material-based interaction system for producing interactions such as audio, particle, and decal interactions.Impact是一个强大而灵活的基于材料的交互系统，可以产生诸如音频、粒子和贴纸等交互效果
So what can you do with Impact?
Here are just a few examples of how you can use Impact to spice up your game:
PHYSICS INTERACTIONS
• Play audio when physics objects collide with each other with sounds based on the collision velocity and the objects' materials.
• Play sliding and rolling sounds.
• Emit particles on collision.
• Leave decals behind on collision.
• Works great with rigidbodies connected by joints as well as ragdolls.
