Merging Objects vs Instances
I have pretty heavy CAD objects with hundrets of small parts which I want to import in UE for VR. I poly-reduced the geometry from several million polygons down to about 100.000 polys with almost zero visual difference using Houdini…
Now I want to import these geometries into unreal but I have read about different approaches on how to deal with geometry in UE
- merging objects by same material
- merging objects by same object category eg. bolts, screws…
- merging everything into a single object
- not merging objects at all, but using instances for every duplicate object
Also, the geometry could be reduced even further by deleting all occluded faces but that would mean I would lose the ability to use instances - on the other hand this would save a lot of light lightmap space since all unnecessary hidden would not be part of the UV-layout…
For me instancing would make most sense, but I was wondering what would happen to the lightmaps of each object? - would that mean UE generates a lightmaps for EVERY small instanced object?
Any recommendations on how to handle this geometry in terms of merging/instancing regarding performance/draw calls?