Artifacts appear in the distance field when creating a steep cliff in a Landscape.

(This is a translation of a [Japanese [Content removed] by sugao_reiichi.)

Thank you for your continued support.

When creating a nearly vertical cliff in a Landscape, artifacts appear in the distance field. To be specific, sharp, pointed shapes emerge in the area above the cliff.

To confirm the issue, take the following steps:

(1) Create a new level.

(2) Add a Landscape to the created level.

(3) Create a steep cliff using the Landscape tool.

(4) Create a new material. Multiply the DistanceFieldGradient node by 100. Connect it to the emissive output.

(5) Apply the created material to a mesh such as a Cube. Check the distance field around the cliff in the level.

I have attached screenshots for confirming the issue.

The first image shows the appearance of the created level.

The second image shows that pillar-like artifacts appear in the distance field near the cliff.

The third image shows no issue occurs with a cylindrical shaped static mesh actor, resulting in correct rendering.

If there is any possible workaround to avoid this issue, please let me know.

Thank you.

Hello! Thanks for reporting this issue. This is a known issue with the DistanceFieldGradient and is a regression from 4.27. As a potential work around you can try to take a few samples and average the results, similar to the DistanceFieldApproxAO implementation. Here is the Jira link for tracking: https://issues.unrealengine.com/issue/UE-150397