My static meshes are glowing rainbow

Hey All,

Thanks in advance for any help!!

I added a set of meshes (trying my hand at a modular approach using 400x400x20 panels to test fps and rendering) as a composite blueprint and added this as a child actor to a blueprint that finally is positioned onto the main level. I am using the standard 400x400 wall in the architecture folder and only added a collision primitive. The 400x400x20 panels are positioned adjacent to each other. Every time I start the gameplay, there is a different rendering experience (sometimes only one color glowing, sometimes no glowing at all, but the panels are not showing the correct shading, sometimes the panels are glowing all sorts of colors).

The glowing seems to be only on the shaded portions (opposite side of the panel where the directional light would be shining); however, the issue is still present without the directional lighting.

A post processing volume is not used, but the ambiance seems to be showing as if there is a bloom effect.


What does your material look like for those objects? The glowing comes from the emissive value in the material output.

There is no material applied. I’ve tried this with standard brush converted to mesh without a material applied, and with a material applied. Same odd emissive behavior. Also, sometimes they are not emissive at all. The issue seems random.

Correction. This particular static mesh uses M_Basic_Wall material, but this issue occurs with the default material as well (the material used for the BSP brush).

Take a look at this thread:

"Does the artifact go away when you set the ‘r.Cache.LightingCacheDimension’ console variable to 128? There’s a bug with many (>1728) movable components right now that will cause this. Instanced foliage currently does not support lightmaps correctly which are used when the components have static mobility, so both routes are a bit broken. "

Thanks for the link. Where is this variable located in a blueprint project?