Unreal 5 interactive walkthrough test with Lumen

Youtube Video

I’ve been testing Unreal 5 with my ArchViz User Interface Project from the marketplace. Here is what I found:

  • Blueprints seem to work just fine between both engine versions
  • If you create a new ArchViz project the default for reflection captures is 2048 and the project will crash if you have more than a few of them in the scene. You won’t need them with Lumen anyway.
  • Lumen needs to be enabled in the project settings along with Hardware Raytracing (2 times) and ‘extended exposure range’
  • I disallowed static lighting in the project settings and set all lights to mobile. You may have to rebuild the lighting once after the editor restart to remove all lightmaps.
  • Removed all post process volumes and put a single one in each level with only Lumen quality set to 4.0 for GI and reflections. I reduced Bloom intensity to 0.1
  • Disabled the skylight as it does seem to make the scene look worse. You get a long way with bounce light only. Increased the sun intensity (directional light) to 50 or 100 lux
  • Too many lights will slow down the scene a lot. But you don’t need that many lights as bounces will light up most of the scene.
  • Be carefull with emissive materials. They can be used but need to be turned down so they don’t interfere with the lighting itself.
  • Mirrors do not work very well with Lumen at the moment. I removed all planar reflection which don’t seem to work at all and left the render to texture cubes on the smaller bathroom mirrors. I had some problems with them in the packaged build. I am not sure why but they left a green glow on the walls. I tried so many settings that I don’t know at the end what actually removed the glow.
  • If you use any movies played on a TV they have to be in the Content/Movies folder or they won’t work. I couldn’t add another directory in the packaging settings. They would run fine in the editor but not when packaged otherwise.

I’ve been always an advocate for baked lighting. But now I think that Lumen actually looks better than baked lighting and it takes away all the problems with having movable doors or switching furniture. And setting up the scene without needing to build lighting is like a dream.

You just need to take into account that some things like landscape, water, mirrors or subsurface materials or vertex shaders (moving plants) do not work well or at all right now.

I didn’t have luck with setting reflections to raytraced instead of lumen but I didn’t try very hard.

Here is the the packaged project if anyone wants to have a look.