Lighting rebuilt causes shader issues

Hello,
I fixed my "Lighting needs to be rebuilt’ issue with the “Build Lighting Only” thing. But now, it seems that the shaders have disappeared, or the lights are too strong. I think it has something to do with the shaders. Here’s the “Message Log” I get after building the lighting only:

Error Veil_N090212_3ds Object has overlapping UVs.

Info Veil_N090212_3ds Lightmap UV are overlapping by 50.0%. Please adjust content - Enable Error Coloring to visualize.

Error PointLight5 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error PointLight11_10 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error PointLight2 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error PointLight12 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight21 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight42 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight22 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error PointLight6 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight41 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error PointLight4 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight31 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight36 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight43 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight11 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight16 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight35 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight27 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight40 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight24 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error PointLight9_14 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight15 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight20 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight4 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight8 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight37 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight32 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight25 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight28 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error PointLight_3 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight17 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight12 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight3 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight7 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight38 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight33 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight26 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight23 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error PointLight3 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight29 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight30 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight10 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight18 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight39 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight6 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight13 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight34 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight14 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight_1 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight19 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error SpotLight2_12 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Error PointLight10_2 Severe performance loss: Failed to allocate shadowmap channel for stationary light due to overlap - light will fall back to dynamic shadows!

Here’s how it looked like:

And here’s how it looks now:

Could someone help me? Thanks!

You can only have 4 overlapping stationary lights in an area. This is why you’re seeing the error and the red X on all your stationary lights. When they have the red X they revert to dynamic lighting which can be expensive if the light is casting a shadow.

The errors above also mention that you’re getting overlapping UVs for your lightmaps. Since stationary lights bake static lighting for static meshes you cannot have overlapping UVs for your meshes otherwise the baked lighting will not look correct.

Whatever this object (Veil_N090212_3ds ) is it has UVs that are overlapping by 50% and will need to be fixed to get rid of the error.

Thank you!

Is it possible to come around this limitation for performance testing, i mean this gotta be an arbitrary limitation and not a real technical limit.

Not an arbitrary limitation. You can read more information here: https://docs.unrealengine.com/latest/INT/Engine/Rendering/LightingAndShadows/LightMobility/StationaryLights/index.html

Also read this post where Daniel goes into more detail about Stationary Lighting. How does the Unreal Engine blend baked and dynamic shadows, what method? - Rendering - Epic Developer Community Forums