I am working with HDRP 12.1.5 and using the Terrain tool, I am using the “Paint details” tool to place various prefabs such a grass and rocks. I have a problem where the prefabs placed on the terrain with the paint detail tool seems to receive no lighting/shadows. The terrain itself receive shadows, but not the detail meshes.
Here I made a prefab with basic white boxes, those with the correct lighting were placed by hand, those with the broken lighthing are placed with the terrain details tool. It is very clear there’s a problem when you compare them:
Enable contact shadows and turn it on.
You have to enable it in a few places (as usual with HDRP)
enable in active HDRP asset, Directional light, post processing global volume
default distance is 50, you can increase it and mess with the other settings
Also try disabling light layers in your HDRP asset. There used to be a bug that messed up detail visuals when light layers were enabled. It’s fixed in some version but not sure if yours was one of them or not.