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?
According to the docs, the specular value should be left at 0.5 for almost all materials. Everything else looks correct, only the light source reflections look strange.
Can you take a video of the camera moving to make the stripe transition more visible? Also, what does the PT output?
When the camera moves horizontally or zooms in and out, the stripes also change. Slight adjustments to the camera angle will change the direction of the stripes. With a more significant change in the camera angle, the stripes will disappear. This issue does not occur in offline rendering.
Is there any plan for native support for Restir GI in Lumen?
The prototype hasn’t been updated for a year, and I wonder if the idea has been completely abandoned or if there are plans to revisit and complete it.
Also, for reflections, will there be an option to recalculate accurate reflections with proper shading and high-quality GI in the future?
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restir again? what even is this? reading papers…
restir is basicly temporally and spatially accumulated lighting. isn’t that what taa and the motion and sample history does? and everybody hates it, apparently.
sure… lumen uses irradiance probes instead of pathtracing, which makes it a lil coarser, but also compatible with lower end hardware. it runs in dx11. console level. hmm
until the next gen comes out with raytracing features restir can wait. a lil bit. that’s my opinion. i’m just a game dev. yo
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Nvidia is already working on integrating ReSTIR GI into their branch as an additional option for developers using Lumen hardware, replacing the probes in Lumen. Epic had started a prototype to further enhance Lumen, but it hasn’t been updated in a long time. I was wondering if Epic plans to revisit this project and whether they will eventually offer a more advanced method for recalculating reflections to ensure they are accurate, without relying on the surface cache.
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I’ll respond but put it in blocks so as to not throw the thread more off-topic:
Summary
I think Epic is unlikely to implement a renderer like this for real-time anytime soon. I’m familiar with the paper, and the performance numbers don’ currently look doable for real-time, regardless of the graphical quality.
Furthermore, iridescent effects like scales, soap bubbles, metal, etc. are all things that substrate makes it quite possible to convincingly fake. In particular, the SpecularLUT node lets you create a very convincing illusion of thin-film interference when deployed properly, and I don’t think that kind of physical accuracy is as big a priority for UE as performance is. Not to say I wouldn’t love more PBR capabilities in-engine, just that I don’t think it’s likely anytime soon.
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@Krzysztof.N There’s a lumen bug in 5.4 that I’m attempting to understand (LMK if it’s already been fixed):
In the safe house content pack, I keep receiving circular rendering artifacts in the lumen scene on these metal pipes. The normals don’t appear too unusual to me, and I can’t figure out any obvious reason for the errors. Lumen scene detail is 3, lumen scene lighting is 8, hit lighting enabled, normal proxy geometry mode (although nanite geometry also demonstrates the artifact).
This sheet also demonstrates rendering artifacts, but it includes this fragmented appearance in the reflections view for no discernible reason. Enabling/disabling WPO on the cloth makes no difference whatsoever, and both sides of the material exhibit these artifacts. The PT renders the scene as expected.
Is the pipe hallow? That and the sheet might be having artifacts due to being thin.