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Foliage Optimization

For the sake of context, my goal is to create a very dense forest, so I want to pull no punches on optimization. I want to see if I can go a step beyond LODs and the foliage system’s instancing of entire models, but also have each tree instance made of instanced components.

If I create a model of, say, a tree, and I construct said tree with many instanced meshes for the branches and leaves, do these instances translate into Unreal’s instancing system, or is the instancing done in my modelling program lost on import?

If not, would there be any performance gain (or loss) to using the foliage system to just place main trunks, and then using particles to place branch and leaf instances?

Apologies for responding without an answer, but I have been wondering the same thing for a while and would definitely been interested if someone might know the answer to this. I would have thought that trees made of smaller instances would be preferable optimization wise, but I am guessing it might get quite tricky having them LOD correctly and efficiently.

No worries. When I get the time in the next week or so, I’ll be running some tests. I’ll share my results here.

I did find that the FBX format supports instancing so long as the instances share the same material. The question is still whether Unreal respects that, being a different architecture and all.