We’re exploring Runtime Cell Transformers for converting static meshes to instanced static meshes. I noticed that the static lighting data is not transferred from the source static mesh components to the new ISMs. I understand that RCTs are an experimental feature, are there any plans to support static lighting in UWorldPartitionRuntimeCellTransformerISM?
If not, would there be any potential pitfalls in extracting lightmaps, shadowmaps and their respective coordinates from the original static mesh’s FMeshMapBuildDataand referencing them in the generated ISM?
There are no current plans to develop this feature, but it’s not crazy to think it would be possible.
Without having extensively investigated it, the main pitfall would lie in making sure the baked SM lightmaps are suitable to be handled as ISM lightmaps, like making sure all the instances have their lightmaps in the same lightmap resource cluster. The WP static lighting builder already enforces actors in the same cell to be in the same UMapBuildData object but doesn’t enforce the resource cluster part since it would be a new requirement. So beyond an initial POC implementation this would need to be added to ensure any cell that would need more than one resource cluster wouldn’t intermittently fail to generated proper data.
Great, thank you for the quick response!