UE5 "Exploding" Hair

The Cloth simulation time step smoothing is interfering with the substepping fix for multi Temporal Samples by changing the very variable DeltaTime and causing some large errors in the cloth simulation due to increasing/decreasing convergence.

Simulating with p.ChaosCloth.UseTimeStepSmoothing 0 fixes the issue.

This Cvar needs to be added to the MovieRenderPipeline startup sequence to solve this issue for everyone.

Cloth or hair , it is the same Chaos Physics , Should be fixed in UE5.2 😁

Author	Message
lightbearer	lightbearer Posted 3 Years Ago
Veteran Member Group: Forum Members Last Active: 6 Months Ago Posts: 88, Visits: 530	I'm not sure how to solve this issue. The video below shows what's happening with standard cloth settings for hair. I have the same issue when I paint different weight maps and use the anim stiffness mask as shown on Reallusion's YouTube video. If I simulate the render and press play in the timeline, things work correctly. When I render with the legacy Movie Renderer things work fine, but when I use MRQ, the results are chaotic. Suggestions? Is there are a CVAR I need to use? hair builder iclone 8 ue5

StyleMarshal	StyleMarshal Posted 3 Years Ago
Distinguished Member Group: Forum Members Last Active: 2 Years Ago Posts: 5.8K, Visits: 14.3K	The Cloth simulation time step smoothing is interfering with the substepping fix for multi Temporal Samples by changing the very variable DeltaTime and causing some large errors in the cloth simulation due to increasing/decreasing convergence. Simulating with p.ChaosCloth.UseTimeStepSmoothing 0 fixes the issue. This Cvar needs to be added to the MovieRenderPipeline startup sequence to solve this issue for everyone. Cloth or hair , it is the same Chaos Physics , Should be fixed in UE5.2 😁

UE5 "Exploding" Hair

UE5 "Exploding" Hair

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