What you're seeing
A mesh region appears pink in Surface Cache view, contributes no bounced light, and appears black in reflections.
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
- 01Open Lumen Surface Cache view and locate every pink region that matters to lighting or reflections.
- 02Visualize Card placement for the affected mesh.
- 03Increase Max Lumen Mesh Cards only as far as the mesh needs.
- 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
Surface Cache view
View Mode > Lumen > Surface CacheColors uncovered Surface Cache regions pink.
Card placement
r.Lumen.Visualize.CardPlacement 1Draws the capture positions generated for mesh material properties.
Static Mesh setting
Build Settings > Max Lumen Mesh CardsRaises the number of capture Cards generated for a complex mesh.