In UE 5.6, heightmap texture compression was introduced. The original implementation did not consider duplicate pixels along subsection and shared textures (multi-component) boundaries. As a result, the normals along the edges are incorrectly generated and show visual artifacts. This is more noticeable where there is high heightmap variation.
Also tested on //UE5/Release-5.6/, CL: 45232827
This artifact did not reproduce on UE 5.5.
Public Forum: https://forums.unrealengine.com/t/world-partition-landscape-auto-material-issue-with-5-6-non-nanite/2652404/12
1. Download the Licensee's test project (see addl info URL)
2. Package the project
3. Open the packaged game
4. Run "toggledebugcamera"
5. Fly to where you can see the specular reflection of the skylight on the landscape
6. Observe a square pattern, aligning with the landscape tiles. It might only be visible in the area with the spline.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-351892 in the post.
| 0 |
| Component | UE - Graphics Tools - Terrain |
|---|---|
| Affects Versions | 5.6, 5.7 |
| Target Fix | 5.7.1 |
| Created | Oct 31, 2025 |
|---|---|
| Updated | Nov 13, 2025 |