How does the sphere mode in 2D work? I’m noticing that certain colliders in my 2D game aren’t being detected when using the “ray” mode. For example I have several “wall” sprites with colliders. In one example I have a composite collider. When I place the object into my scene and run a sample graph scan, it doesn’t get marked:
When I switch from “ray” from “sphere” collider types, and change the “diameter” to 0.75, the cell gets marked as unwalkable correctly.
I’m trying to understand why one works but the other doesn’t, yet the collider shape/size remains constant.
I looked around the site/these forums for a good explanation but didn’t see it, so I apologize if I’ve missed it. Is one or the other better for performance?
The difference between ray and sphere is that the ‘ray’ mode will only check for obstacles exactly in the node’s center. The sphere mode will check for any obstacles inside a circle with the corresponding diameter (note that 1 always corresponds to the width of 1 node).
These names are for 3D, for 2D the analogue names would be ‘point’ and ‘circle’/‘disc’.
See also
https://docs.unity3d.com/ScriptReference/Physics2D.OverlapPoint.html
https://docs.unity3d.com/ScriptReference/Physics2D.OverlapCircle.html
Some other images that might be useful:
Collision Testing Height (for rays and capsules):
Height Testing ‘Ray Length’:
I’m not sure why your collider wouldn’t get detected by the ‘ray’ mode though. Perhaps Unity’s OverlapPoint method call does something strange.
