Tracing for a physical material breaks and returns “DefaultPhysicalMaterial” if collision of the tested mesh is set to complex and a custom “ComplexCollisionMesh” is set.
Steps to reproduce:
- Import a mesh
- Set collision to complex
- Import a simplified collision mesh
- Assign physical materials to created materials
- Set “ComplexCollisionMesh” of the original mesh to use simplified collision mesh
- Test with line trace or any other trace
- Physical material of hit response should be “DefaultPhysicalMaterial”
Expected behavior would be correct physical material returned, which is exactly what is happening if you bring custom collision mesh into the level and test against it. For that reason, current workaround is:
- Bring custom collision mesh into the level
- Align it to the original mesh
- Disable collision on the original mesh
- Disable visibility on collision mesh (This will force you to use other trace channel than “ECC_Visibility”)