I’ve found an issue in Mutable with skeletal mesh asset which had assigned for LOD3 different material (from Material Slots) than LOD0 for the same section #.
Auto LOD Strategy = Automatic from mesh
The compilation of Mutable asset stays silent, preview is empty, but the output log states i.e.
LogMutable: Error: Failed to generate SkeletalMesh for CO Instance [CustomizableObjectInstance_151]. CO [MCOR_Hairs] is missing geometry for LOD [3] Object Component [0].
It is known bug or is there any workaround how to achieve successful compilation?
Tested in 5.6 and 5.7.1 with the same negative result.
This isn’t technically a bug, but I can understand why it feels that way. When you’re using the LOD strategy Automatic From Meshand the compilation hits the same index mesh section that uses a different material slot, it’s technically a different mesh section. So you need to tell the MeshComponent node which section that is.
(Image below is a repro that gets the same message from the Mutable Sample Project)
[Image Removed]This will allow you to generate that mesh, but I’ll caveat that it still uses that other material slot, so you will end up with two material slots in your mesh, both filled with the same material.
The benefit of this, though, is that you don’t have to define the material information for LODs 1 and 2 or LOD 4. If you are using the same material for LOD 3&4 I would recommend combining their material slot in your source. If you want to keep them separate, follow the above scheme. Unfortunately, there is no way to combine material slots in Mutable at the moment.