UE5.8 Procedural Vegetation/Megaplants Shadow Cache Invalidation

Currently, the Shadow Depth pass takes around 8–11 ms when using a dynamic day/night cycle with the new skeletal procedural trees. From what I understand, this is because the shadow cache invalidation method for skeletal trees is currently set to Always.

The old foliage paint tool had options to set shadow cache invalidation to Rigid and Static, which allowed the trees to move using World Postion Offset while keeping their shadows static, resulting in much better performance.

It would be really helpful if similar Rigid and Static options could be added for the new skeletal trees as well. This would make them much more practical for large environments with dynamic lighting and day/night cycles.
I hope the Team at Epic considers this for UE5.9
Not every tree needs to have its shadow updated every frame with the wind
Thanks

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The Rigid/Static options already exist but aren’t honored for Nanite skeletal meshes. There is a JIRA in here internally for it so it will get fixed at some point.

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Well, that’s great to hear. But are you guys also working on a way to have shadows move with the wind without having to pay the cost of updating the Virtual Shadow Map every frame? Since the wind animation is usually just a single looping animation, I was wondering if something similar could be done to what you guys implemented for Fortnite in UE5.1, where it was mentioned in an article that you were using baked World Position Offset animation to reduce the cost.

Something along those lines but for skeletal trees would be really useful.