I created a material with the DistanceToNearestSurface divided by 1000 and plugged into the Emissive channel. I set this material to both a landscape and a Floor static mesh (with Affect Distance Field Lighting turned off) to test. Finally I added two box static meshes to the scene and here is the result.
As you can see, the distance field works fine on the Floor static mesh on the right, but is broken on the landscape on the left.
You can see here that the mesh distance field looks correct.
However, if I look at the global distance field, what is this?
The landscape is a big blob in there, so I have a feeling the material is picking up on some distance field information from the landscape itself from this global distance field. Is this intentional or a bug?
I couldn’t find an Affect Distance Field Lighting option to turn off for the landscape, so is there some way to stop it adding to the global distance field?