Lumen Surface Cache Gap

Likely causes

• The mesh is too complex for its generated Lumen Cards.
• Walls, floors, ceilings, or an entire room were combined into one interior mesh.
• The material uses view-dependent logic that cannot be captured from the Card view.

Check in this order

1. 01Open Lumen Surface Cache view and locate every pink region that matters to lighting or reflections.
2. 02Visualize Card placement for the affected mesh.
3. 03Increase Max Lumen Mesh Cards only as far as the mesh needs.
4. 04If coverage remains poor, split the mesh into simpler parts. Provide a Ray Tracing Quality Switch path for view-dependent material logic.

Views and commands

Epic documentation