How well do stochastic shadows do with rect lights? I haven’t tested it in several months but the last time I tried ManyLights with multiple overlapping rect lights the shading basically broke down into temporally-unstable soup. If things are better now I will be very happy.
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depends how much you use and abuse them. good detail texture work will always cover up the scatter noise.
simple dev shot. all maxed out with cvars on begin play.
I think stochasitc + area lights seem ok in 5.4.3. See pic, no artifacts or unstable things going on although maybe this scene / setting might not be the best to investigate your earlier observation. What kind of scene / settings did you test?
sry… but a screenshot doesn’t show the temporal noise.
and… yes… on white or monotone unicolor surfaces like archviz does it is present. it cannot be avoided. this is just how the scattering works. for archviz you should bake the stuff for a stable result. in games you can deal with it and add details.
Unfortunately, the video compression seems poor enough that I’m not sure I can read shadow characteristics from it, but in general it does seem like ManyLights is significantly better quality. Besides, it’s designed for cheap local lighting, not hero lights, so if it’s good enough for that purpose I have no qualms.
I assume stochastic shadows requires hardware raytracing?
nope. without hardware raytracing it’ll use a combination of screen traces and distance field shadows. the typical screen space occlusion artefacts and distance field resolution limits apply.
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Not sure about the naming, but it requires Ray Tracing. I mean: if you disable All ray effects cvar, you won’t have stochastic shadows. If you disable Lumen Hard RT cvar, they will still work (because it seems to rely in RT shadows, not Lumen). But if you disable Support hard rt in project settings, they don’t work too.
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manylights does not need raytracing. it still works without it. did the shutdown via project setting. also portrayed are screen space artefacts and you can see the distance field shadows flip on the static mesh tree (hollow df) and the “bunker” box edges.
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I’m quite sure about my test (however I did it quite quickly, in 5 minutes and remotely), but now only @Krzysztof.N could officially confirm one of the ‘theories’.
I saw a few videos regarding Nvidia’s new wave-based real-time light simulation which provides better quality and more performant than Ray tracing.
is there any possibility for Unreal Engine to adopt this new technique for better quality and performance?
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Hi guys,
Do you have any tips on how to get rid of the reflections of the light sources?
So far what we did was we turned off the lighting channels for the glass meshes, that seemed to help, although not an ideal solution:
But for meshes which have multiple material slots, it is not an option unfortunately. Although we could break up meshes into multiple parts manually, it is not an option for runtime imported meshes:
This issue seems to be present both in Lumen and Pathtracer. If we reduce the light source radius, the shadows will look too hard and there will still be very bright small dots visible. An option to adjust lighting channels on a per material slot basis would be really helpful to solve this issue, although not sure how much work that would involve for the engine developers.
Any other ideas for it?
that’s a feature. the reflection is clamped inside of the attenuation radius. specular scale can remove it entirely.
But turning down the specular scale will affect all other meshes too which are being lit by the light source, resulting in an unrealistic look, lacking the specular highlight…?
maybe use the translucency volume lighting mode for the glass. it does not support specular highlights.
Do you have a link? I am unfamiliar alas.
this is the video explaining the paper based on wave based lighting.
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A simple structure reflects light after being illuminated by the sun, but at certain angles, the reflected light appears with stripes. Increasing the Final Gather quality to 6 makes these stripes even more noticeable. This is very strange. How can I eliminate these stripes?
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Have you tried editing how material reacts with specular?