The desired behavior from a user perspective here is that they'd be able to use Static Switches in a decal master material to toggle different features and behaviors. In the above setup, if I set the Use Base Color ignore-switch to False, I would expect and want my decal to use only the DBuffer Normal blend mode.

I've attached a project with the materials and scene setup necessary to replicate the issue.

Steps to Reproduce
  1. Create a new material, set its domain to Deferred Decal, and its Blend Mode to Translucent.
  2. Connect to the Normals pin this texture: Texture2D'/Engine/Functions/Engine_MaterialFunctions02/ExampleContent/Textures/newhplaneNormalsMap.newhplaneNormalsMap'
  3. Connect a SphereMask to your opacity pin: 
    [Image Removed]
  4. Create a new Vector Parameter named "Base Color" to the Base Color pin and set its value to 1.0, 0.0, 0.0, 0.0.
  5. Create a new Static ignore-S.witch Parameter named "Use Base Color" and connect the Base Color parameter to True and 0 to False. Connect this to Base Color.
  6. Create a two new child instances of your material and apply them to a new Decal Actor. In one, set the Use Base Color flag to True.
  7. You should now see the decal affect the scene as expected if the ignore-s.witch is True.
    [Image Removed]
  8. But if the ignore-switch is false, it uses a a Black base color.
    [Image Removed]

This behavior can also be seen using a similar setup with Material Attributes:

[Image Removed]

Have Comments or More Details?

There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-129570 in the post.

Login to Vote

ComponentUE - Rendering
Affects Versions5.05.1
Target Fix5.2
CreatedSep 28, 2021
UpdatedJul 20, 2022