Description

Spawning an actor with Chaos cloth causes a hitch when LODs or Self-Collision are enabled on the cloth. LODs and Self-Collision seem to compound the issue.

Self-Collision requires a collision simulation mesh be generated for each LOD, which leads to long CreateClothActor times. Without LODs, CreateClothActor takes less than a millisecond. With LODs and Self-Collision, it can take north of four milliseconds, depending on the number of LODs and the cloth's geometric complexity.

This long cloth creation can become an issue when spawning an actor that utilises cloth during gameplay.

Steps to Reproduce

1. Create a project
2. Add a character with cloth that does not use LODs
3. Add a character with cloth that does use LODs
4. Compare the SpawnActor time in Insights between them
5. Add Self-Collisions to both characters
6. Repeat the Insights pass and record the times.
7. The character using LODs should be somewhat slower than the one without, and Self-Collisions should be significantly slower

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Unresolved
ComponentUE - Simulation - Physics
Affects Versions5.15.35.3.1
Target Fix5.5
CreatedJan 21, 2024
UpdatedJun 20, 2024
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