Hello,
I want to optimize the ray tracing representation of a character’s card-based hair when using the Groom asset. The cards should be either less dense in ray tracing or excluded entirely for smaller Grooms such as eyebrows and eyelashes. What would be the suggested way of going about this?
Traditionally, when hair cards are part of the skeletal mesh itself, such changes to the fallback mesh density or excluding sections with “Visible in Ray Tracing” work as expected. However, when using a Groom asset, the mesh that ends up in the ray tracing scene is the same mesh that is used for rendering in the scene. The strand-based hair system offers voxelization for a simplified ray tracing representation. However, I’m not sure what ray tracing optimizations are possible for card-based hair via the Groom asset.
In the attached pictures you can see an example of the “Visible in ray tracing” toggle only working on the hair card mesh itself, but not when that mesh is inside a Groom asset. The same issue applies when changing fallback / ray tracing mesh density. If possible, I’d like to keep using the Groom asset, so I can also easily switch between hair strands and hair cards and make use of the hair guide-driven workflow.
2026-03-24 19_49_24-Hair_S_UpdoBuns_LOD0.jpg(185 KB)
2026-03-24 19_49_36-Slash - Unreal Editor.jpg(67.5 KB)
