To fix DLC scanner arm bug - ignore Colliders with triggers.

[Dunbaratu]

For a long time LaserDist had a bug with the Breaking Ground DLC scanner arm parts, where the laser would pick up a hit on the invisible sphere around the scanner arm that the game uses to detect if rocks are in range or not.

It turns out this sphere is a trigger collider, which is not a "real" collider, in the sense the physics engine behaves as if it's not physically there - it doesn't bump into things. Instead it passes right through them with no effect, etc. The only purpose of a trigger collider is to fire off a callback hook to inform the programmer something is touching the collider, then the programmer does whatever they want with that information. The physics engine doesn't care about it.

This is why the scanner arm sphere is on layer 15 where the terrain should be. The sphere touches a terrain rock and the game responds to that trigger callback to learn that the rock is in range.

Physics.Raycast used to be unable to stop hitting trigger colliders back when LaserDist was first developed. But more recently it added a new parameter to Raycast that lets you specify if you would like it to ignore triggers. LaserDist could use that and fix a lot of headaches.