The Vertex Interpolator Material Expression appears to collapse separate instances from separate Material Layers, leading to visual artifacts when used.
Also tested on UE5_Main, CL: 34200103
1. Download the Licensee's test project and open (see addl info URL)
2. Open the Material Layer asset "/Game/Developers/ignaciodecia/EpicBugTest/ML_MaterialLayer"
3. Observe the usage of the Static Switch Param "bUseInterpolator"
4. Open the Material Instance "/Game/Developers/ignaciodecia/EpicBugTest/MI_TwoLayeredMatInst"
5. Observe that it has two layers of the type "ML_MaterialLayer".
6. Enable the Static Switch Param "bUseInterpolator" on the top layer, then on the background.
7. Observe that only the top blue layer is visible. (Bug)
8. Disable "bUseInterpolator" on the background layer.
9. Observe that nothing has changed - only the top layer is visible. (Bug)
10. Disable "bUseInterpolator" on the background layer, and re-enable it on the top layer.
11. Observe that the material works correctly with both layers visible.
12. Observe that "/Game/Developers/ignaciodecia/EpicBugTest/MLB_SimpleDiamondBlend'' and its contained Material Function does not do anything beyond a simple Material Attribute Blend
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-217497 in the post.
| 2 |
| Component | UE - Rendering Architecture - Materials |
|---|---|
| Affects Versions | 5.4, 5.4.2, 5.5, 5.4.1 |
| Created | Jun 7, 2024 |
|---|---|
| Updated | Jun 25, 2024 |