One problem for putting in quality presets is that quality depends on how much light is in your scene.
On the titanic, I can bake an outdoor deck scene with 512 samples and it looks great. Perfectly clean.
On some of the interior spaces, I need 35,000 samples to get a similar amount of quality.
I noticed in the Unreal Roadmap there is an entry regarding adaptive sampling for Pathtracing. If there is any way this can be implemented for GPULM, I think that would be a big improvement going forward.
For your incorrect bounce problem, which engine version is this, and do you have the UE5-main fixes? I had this problem to an extreme until I compiled a custom engine version with the fixes.
Notice the light coming from underneath the machinery, which is just a solid floor.
While we’re on the topic of improvements.
I think there is still quite a bit of underocclusion, especially on thin meshes, which often will simply not have any shadow.
Perhaps this was changed in 5.2, where we had an overocclusion problem. There must be a possibility for a middle ground.
The ability to natively work with sublevels would be extremely helpful. I have been using a workaround of putting my atmosphere into a separate sublevel and using a different lighting channel so it doesn’t ruin the lighting in my main levels. This is a gigantic pain because I need to create “light blocker” levels, which are all the meshes around the level I want to bake that would affect the lighting of the primary level. I can set the lightmap resolution of those to minimum, but it still adds a lot of baking time, and making those levels is a big pain, since any changes made anywhere need to be manually propagated through all these light blocker levels.
For volumetric lightmaps, I put a temporary “light builder” level in the primary level that I want volumetric lightmaps for. This consists of the same meshes as are in all my sublevels, but all the lightmap resolutions are set to minimum. I bake my VL and then discard this sublevel. The VLs stay in the primary level.
GPULM seems to have a lot of problems with thin translucent materials. In this scene, Other than a few dim interior lights, the main light source in the scene is a stained glass window.
All this random noise goes away if I change the window material to Default Lit.
A super aspirational feature would be to have the ability to lightbake individual objects, like the way Vray for Unreal does it. That way if I discover a single lightmap is bad after doing a 30 hour bake, I don’t have to rebake the entire level after making the fixes.
