Hi guys! I've been working on personal environments in UDK to try and develop my level building skills. Currently, I'm working on an outdoor scene using Landscape and foliage. I'm getting pretty wicked display errors on my foliage after running lightmass:


In addition to the crazy colors, the cast shadows on the trees are also badly distorted.

I'm not sure what I can say to help diagnose this issue. Building lighting at Preview quality, lightmaps are disabled on the foliage meshes anyway. I have a lightmass importance volume, and a postprocess volume for some DOF and color correction. There is a dominant directional light, a skylight, and a heightfog. That's about it!

I looked around online, didn't find much, but did see that some people had foliage problems due to their gpu. Here are my specs:

i5-2500k
560ti 1024 mb gddr5
8gb pram

Here is what the scene looked like prior to running lightmass.

I've tried building lights in 64bit and 32bit modes, but didn't avoid this problem in either. the problem persists in PIE mode.

On an off note, does anybody know of any guides for managing or consolidating lightmaps? In another one of my scenes, lightmass takes forever due to all of the maps updating on my static meshes, but isn't the point to consolidate them into a single map? I've never found any tutorials on how to do this.

Thanks for looking!

Get rid of skylight and use the environmental colour found in world properties/lightmass. Skylight is deprecated old tech, it was used before lightmass came to be.
Blotchy shadows on the ground are because your lightmap resolution on the terrain is too low.
What exactly do you mean that lightmaps are disabled on your foliage meshes? You mean that you're using vertex lighting? It's more wasteful on memory than lightmapping, FYI.

You don't consolidate lightmaps, the SDK does that for you. All lightmaps are packed into 1024 x 1024 atlases after lighting build. You should be able to see the lightmap textures in your map package.

As for the funky colours on the trees, I have no idea what's up with them sadly

Ok, thanks for the tip about the skylight.

I "disabled" lightmaps on the foliage by setting the lightmap resolution to zero in the static mesh editor. APPARENTLY that was wrong, because it looks like that is what was causing the crazy colors

I adjusted the Static Lighting Resolution in the Landscape properties, but this adds a considerable amount of time to building, so I may look into cascading shadows that cull in the distance.

After setting the foliage meshes back to 32x32 lightmap res, I can see the 1024x1024 atlases for these, but I still have over 300 lightmap files in my map package. Is this normal? Sorry, I really don't understand Lightmass very well, most of my experience is with Cryengine. I have been looking at the UDN page, but it's slow to sink in D:

Thanks for helping out!

If you are using DominantDirectional light as your sun you can use lower res lightmaps on everything and increase WholeSceneDynamicShadowRadius. So, this way you'll have crisp dynamic cascaded shadows inside that radius which will fade to static lowres shadow maps outside that radius.

If your level is huge then you really have to use the cascaded shadow maps, you can't have a high res lightmap for the terrain without going overboard with level size (Mb wise).