Hi,
We upgraded our project from 4.16 to 4.17, and now lighting build always fails on one of our maps.
Using the LIGHTMASSDEBUG console command, executing UnrealLightMass.exe under debugger, I found an array overrun access occurred.
Engine\Source\Programs\UnrealLightmass\Private\Lighting\Embree.cpp: FEmbreeGeometry::FEmbreeGeometry()
UVs[I1] = V1.TextureCoordinates[Mesh->TextureCoordinateIndex];
num of UVs is 0x00003588, but I1 = 0x00003588. This is overrun.
And I found a suspected mismatch in related variables (by Visual Studio Watch window notation):
- this->Mesh->NumVertices = 0x00003588
- ((Lightmass::FStaticMeshLOD*)((Lightmass::FStaticMeshStaticLightingMesh*)(this->Mesh))->StaticMesh->LODs.AllocatorInstance.Data)[0].Vertices = 0x000035a2
I suppose these values should be equal.
I tried to Build LODs/Build Geometry, but it does not resolve this situation. Lighting Quality does not affect this either.