While enabling Ray Tracing from the start of the project, when user sets GlobalPostProcess Translucency to Ray Tracing, the back-face of the plane is not culled. However, when the translucency is set to Raster, the actor is culled as expected.

This was tested and reported in 4.26 Preview 3 (CL-14488950). This was reproduced in 4.25.3 (CL-13942748) and 4.24.3 (CL-11590370)

Steps to Reproduce
  1. Open Project with Starter Content selected and Ray Tracing enabled
  2. Place actor (ex: Simple Plane) in viewpoint
  3. Select GlobalPostProcess Volume
  4. Under Rendering Feature, navigate to Translucency
  5. Select Ray Tracing
  6. View Actor and note its back-face is not culled

Outcome: the plane is only culled when translucency is set to Raster, when it should be culled with Ray Tracing enabled as well. When Ray Trancing is enabled, the back-face of the actor is not culled.

Expected Outcome: The plane or actor should be culled after selecting ray tracing in translucency

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ComponentUE - Rendering - Lumen
Affects Versions4.
Target Fix4.27
Fix Commit15939003
Main Commit15939003
CreatedOct 23, 2020
ResolvedApr 7, 2021
UpdatedNov 30, 2022