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Performance Drops with Lighting?

I just recently got Unreal Engine 4 and so far I’m really happy with it. I went through the basic level building tutorial before trying to build my own unique one, and it was going perfectly well until I tried adding a couple more Point Lights.
I had 3, and as I tried to put down a 4th and 5th I noticed a red X across them. However the light still shone so I thought nothing of it.
Then I tried building the lighting to get the production quality, and I got this message for the 4th and 5th Point Lights:

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

If anyone could tell me what this message means and/or how to fix this issue that would be awesome!
I’ll also attach the screenshot I took.

Thank you,
Nicolas (ThundurGamez)

That may be too many movable lights in one spot. There are 3 types: static, movable and dynamic.
This thing is easy to exceed on big meshes that are affected by many lights
Your choices are:

  • make less lights
  • make some of them STATIC
  • split big mesh into smaller ones

Not sure if light channels are functional by now you could with them move some lights to separate channels so they did not overlap.

Only four stationary lights can overlap because of the way Unreal optimizes them via shadow maps (viewport > Lit > Stationary Light Overlap) . If you have a stationary sun in the level at all, that means you get 3 more stationary lights to work with. Any extras give that red X and behave as Movable (fully dynamic) only. Dynamic lights and especially dynamic shadows are not optimized at all and are not recommended unless absolutely necessary for a desired effect. If you switch those red-X’d stationary lights to Movable, the error will go away but you’ll have the dynamic lights and no lightmap support for them. Which is totally fine if that’s what you want. I would recommend editing the falloff of those point lights to make sure they don’t overlap too much, because you can have as many in the scene as you want if they are spaced properly.