Light::DeferredSimpleLights(Strata:False,Tile:None) 33 draws 14256 prims 8151 verts
I have a lumen scene with 1 dynamic directional light. That is the deepest the profiling goes. I’ve done all sorts of optimizations and still get very bad fps due to lighting taking a lot of milliseconds. I’ve searched far and wide but haven’t found any good discussion / explanation / help / hints about how to further debug. Might anybody know the best way to get information on why the deferred lighting is taking so long? Do i have to resort to some external (e.g. nvidia) profiling and somehow read tea leaves from those? I feel like this must have cropped up as a perf problem for a lot of people over the years…? Thanks for any thoughts.
some misc notes:
- used large post process volume (1k,1k,2k scale) to set global illumination to None, Reflections to None.
- used Reduction Settings on static meshes to bring down vert/tri counts.
- there’s only 1 directional light, it is movable, i turned off casting shadows. i don’t need it to be movable. i just don’t ever fully understand what happens to lighting if i make it anything else. i don’t want to get back into ever having to “build lighting” at least.
- profiling shows the DeferredSimpleLights is what is killing frame rate, but there’s no more lower level detail to help me see exactly what it is doing in there.
- not using nanite, i don’t have anything that would particularly fit that.
- according to Tools>Audit>Statistics, scene has 338k tris.
- have been making some materials unlit in the hopes it would help.
very stressfully, after trying these kinds of changes, i now somehow have even worse fps, and no way to know why the DeferredSimpleLights is only getting worse.
I just tried using the Shader Complexity view in the editor. There are some white areas that have high PS and VS. They are mostly P_Fire and P_Sparks. I’ve used those in other levels w/out seeing any frame rate issues fwiw… at least I will experimentally try deleting those to see if it changes the fps.
(Light Complexity visualization shows almost everything is pegged white which I super don’t understand. How can I know what that means and what I can do about it, other than that I am doomed at the moment heh? It makes no sense to me since I only have 1 movable directional light in the scene. Light Complexity Freaking Out - #4 by Shmann uh, yeah, so confusing.)