The default view of my scene looks OK. The screen grab shows the “Lumen scene” view. I’m in a class and I think we’re expected to use Lumen for the lighting. In “Lumen Scene” view, pretty much everything is black or glitching, including:
the HDRI sky
an FBX model barn imported from Maya (built with 4 separate meshes)
the landscape, which has one surface material (**I heard that Lumen doesn’t work on landscape…really? So maybe need to cover all exposed parts with megascans?)
foliage doesn’t show up at all.
According to a video by William Faucher, the default view and the Lumen scene view should look roughly similar. But they are extremely, um, dissimilar. How do I fix each of the four elements that’s either black or glitchy?
Second, maybe related question - how do I enable nanite for the FBX? I thought doing that, might make it work better with Lumen.
Thank you so much if someone can help with this mess! -Lisa
Another question related to glitchy Lumen…do I need to break my barn mesh into simpler meshes? I keep hearing/reading that Lumen can’t handle complex meshes. Maybe the barn pieces are too complex?
Here are the stats on the meshes in the barn already:
Walls and windows are a single mesh
Top layer of roof is single mesh
Bottom layer of roof is single mesh
Weather vane is single mesh
For all meshes, there are quads and triangles only, with no manifold geometry. I made decent UV maps for all of them. All of them are continuous meshes except the weather vane. It has several non-intersecting pieces that have been made into one mesh using the “combine” function.
Breaking your barn mesh into simpler pieces could potentially help with Lumen’s handling of complex geometry, but it’s not necessarily the only solution. Lumen’s performance is influenced by various factors, including mesh complexity, lighting complexity, and the overall scene setup.
Since you’ve mentioned that your meshes consist of quads and triangles with no manifold geometry and have decent UV maps, it sounds like they are already optimized in terms of geometry. However, there are a few other considerations to keep in mind:
Lightmap Resolution: Strong text Ensure that the lightmap resolution for each mesh is appropriate. Higher-resolution lightmaps can improve lighting quality but may also increase processing overhead.
Lighting Complexity: Lumen’s performance can also be affected by the complexity of your lighting setup. Try simplifying your lighting if it’s too complex.
Optimization: Beyond mesh complexity, consider other optimizations such as reducing the number of overlapping geometry, optimizing material shaders, and minimizing overdraw.
Testing: Experiment with different configurations to see what works best for your scene. Sometimes, minor adjustments can have a significant impact on performance.
Lumen’s Limitations: Keep in mind that while Lumen is designed to handle dynamic global illumination efficiently, there may still be limitations, especially in complex scenes. If you’re pushing the boundaries of real-time global illumination, you may encounter performance issues.
I really appreciate this information!! As a beginner, I’m not familiar with a lot of this, but I’ll look up the terms and try to make some headway toward a solution. Thank you so much! Your last suggestion makes me think, maybe the extremely high number of plants could be messing up my scene? I was told I have an incredibly huge amount of grass, which was bogging down Unreal, even slowing down camera moves. Maybe reducing the plant count will help with Lumen’s processing issues. In any case, I really appreciate your time!
