Unity Game Optimization - Third Edition

Using trigger volumes responsibly

As mentioned previously, we can treat our physics objects as normal colliders or as trigger volumes. An important distinction between these two types is that the OnCollider...() callbacks provide a Collision object as a parameter to the callback, which contains useful information such as the exact location of collision (helpful to position a particle effect) and the contact normal (useful if we want to move the object after the collision manually). However, the OnTrigger...() callbacks do not provide this kind of information.

As a result, we should not try to use trigger volumes for collision-reactive behavior since we won't have enough information to make the collision appear accurate. trigger volumes are ...