Re-Enable Lightmaps?

Development Rendering
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1

I’m testing 5.0, and am trying to figure out how to disable Lumen and use lightmaps still. I’ve disable Lumen, I think, but when I go to bake the lighting, nothing happens. I’m doing interior architectural scenes with a lot of static lighting, so I need to still use lightmapping. Am I missing some setting to re-enable lightmapping?

2

Did you convert a 4 project to 5? I read something about removing lightmaps. Have you checked them?

3

I believe you can still you baked lights in UE5 ( some info here Unreal Engine 5 and Lumen | Lighting for Archviz - YouTube how to switch).

However I was doing some architectureal viz in UE5 from early access 2 and Lumen is quite ok already in my opinion. Especially preview1 added settings on Lumen cache update speed and quality which is great :slight_smile:

some cosiderations for render archviz queue:

  • set initial warmup frames or extend your clips by ~100 frames in the beggining - this will help Lumen “settle down” and pre-compute
  • set AA for temporal 16 or 32 samples, this will not only increase visual quality but also help Lumen and atmospherics to stay up to date
  • if you are doing dynamic light change with huge impact (such as sun repositioning), slow down your animation or increase temporal AA samples. Lumen needs up to several seconds to completely recalculate global illumination when you make (depends on hw, AA samples, update speed settings, scene complexity etc etc).
  • Turn off shadows where possible, they are consuming a lot of VRAM
  • Try different settings in postprocessing, raytracing etc. Some exterior scenes require several spatial samples as well so that lights do not “blink”.
  • Great channels to follow are VR divison https://www.youtube.com/c/vrdivision , JS FILMS https://www.youtube.com/channel/UCoJun_nF0I90wzXq5t4SdqA and William Faucher https://www.youtube.com/c/WilliamFaucher
4

It is a new project started in 5. The lightmaps are there, and I disable Lumen but when I go to build the lighting, the build lighting window just flashes for a split second and then nothing happens.

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5

Thanks, that info is helpful. I know I need to experiment with Lumen more, as I don’t have a good grasp on it yet. But I’ve read a few posts saying for architectural interiors, it still may not be ideal. For one, I have hundreds of lights in my model that really need to be static for performance purposes. Since it’s a model of an entire building, and I need the lighting to be accurate.

1 Like
6

maybe this will help? Unreal Engine 5 for Beginners Pt. 8 - Realtime Lighting And Baked Lighting - YouTube

7

That doesn’t seem to show how to enable light building. I’ve opened the default architectural template in the engine. But can’t find any way to build the lighting. Like if I disable Lumen, set up some static lights, I don’t even get the alert that says lighting needs to be rebuilt. I’m assuming there is just some checkbox or dialog somewhere that I need to toggle.