Hi everyone,
I have been working on lighting a scene that I am building, but one of the models seems to be having a lighting problem. Most of the model looks fine, but one part of it turns black when baking.
I tried putting a light pointing directly on that part of the model, but that made it look worse.
Try increasing lightmap resolution by 1 or 2 levels. So, if it’s 128, increase to 256 or 512.
What is the mobility of the mesh? and what is the mobility of the primary light on it?
The lightmap resolution was at 64, so I bumped it up to 128, and switched the main light from stationary to static, but that just did this:
Well, switching to static increased the brightness of the blue / metal part, but is still dark on the handle…even the metal of the handle is still dark. Is the mesh static or stationary?
Is the not supposed to look dirty on the blue part? I also see the handle’s shadow has disappeared. Is the main light a point light or directional?
The mesh is static. Yes, the blue is supposed to look dirty. There are multiple lights in the scene, but the one that is shining directly on it is a RectLight.
With stationary lights, there is a limit of 4 overlapping before the engine does not process them all. Go to the StationaryLightOverlap viewmode to check if 3 or more stationary lights are overlapping. The sun (directional light) also is counted for the overlap restriction, and here is the page excerpt on it (scroll down a bit to the overlap info and image example):
https://docs.unrealengine.com/en-US/…irectShadowing
If it’s not that, there’s also a threshold value in Reflections settings of the post process volume. If the roughness is higher than the threshold value (0.6 default), then reflections don’t render, or get diffused into the surface to where they’re not as recognizable because the surface is rougher. This involves more lighting getting absorbed by the high-roughness material, I think, so it shows up darker sometimes in a light bake. It’s especially the case if specular is not correct in the scene or the material of surrounding geometry and the problem mesh.
Ok. All of the lights affecting this object are static (There is a directional sun light, but this part of the scene is indoors, so it doesn’t really affect it). The materials roughness is 0.95, so it is well above the reflection threshold. This was working earlier, but this problem began I modified a bunch of the lights and rebaked it all.
Could you show the lightmap uv of the problematic mesh and the material setting please?
Here is the lightmap. I circled the handlebar’s UVs (There are two in this mesh, one for each side of the hallway. I’m not quite sure where those long UVs cam from, but they don’t seem to be effecting anything):
And here are the material settings for the handlebar:
imo your lightmap resolution is VERY low and that’s causing the problem!
…if you’d put a 128x128 checker map over the uv, you’d see that those parts get a couple of pixel lighting information only!
Ok, thanks. I ended up separating the handlebar to it’s own mesh and that seems to be working. Likely since that gave it more lightmap space just for itself. Thanks for the help!
