Debugging the code I have been able to verify that in GeometryCollectionComponent.cpp line:2318, the if condition happens every two frames.

I think DynamicCollection is not setting all the frames as Dirty, so it skips the geometry update.

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Steps to Reproduce
  • In a new level create a new GeometryCollection with a Cube mesh
  • Enable Chaos debug “p.Chaos.DebugDraw.Enabled 1” and “p.Chaos.Solver.DebugDrawShapes 1”
  • Place the Cube mesh using “Simulate Physics = true” and the Cube_GeometryCollection in the same high height position to watch them fall down.
  • Play as Simulation (PIE) and pause simulation.
  • If you press “Advance a single frame” a few times you'll see how the Cube mesh is update in the correct way but the GeometryCollection need +1 frame to update mesh render.

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ComponentUE - Simulation - Physics
Affects Versions5.2
Target Fix5.4
Fix Commit24509670
CreatedMay 25, 2023
ResolvedMay 31, 2023
UpdatedJun 22, 2023
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