Modulate Blend Mode on Deferred Decals does not blend multiply with background pixels. Transparency for Deferred Decals also does not seem to match with what occurs in 4.27;

Repro Rate: 4/4

Tested this in //UE4/Release-4.27 @ CL#18319896 and could not get a similar result. Though I'm unable to fully regression test as in EA and 4.27, modulate was not supported for Deferred Decals.

Steps to Reproduce
  1. Create a new Blank BP project
  2. In the Content Browser, create and open a new Material
  3. Create a Constant4Vector node
  4. Hook up the node to the Base Color input
  5. In Details, change the following properties:
    • Material Domain: Deferred Decal
    • Blend Mode: Modulate
  6. Save & Apply then close the Material Editor
  7. Drag a Decal Actor into the scene
  8. Set the material to your Decal & observe

Results: The decal, instead of making the underlying geometry darker, simply acts like a default lit decal.
Expected: Decal should should make the underlying geometry darker.

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By Design
ComponentUE - Rendering - Materials
Affects Versions5.0
CreatedMay 10, 2022
ResolvedMay 12, 2022
UpdatedJun 1, 2022