I never would have thought of that workaround but that’s brilliant.
it’s not brilliant but decent. translucent has issues with depthbuffering. it’s rendered in a different pass, afaik. masked does not have that problem. it’s just random solid pixels. hence why i tried it. ez
brilliant would be if it’d dither in the reflection too. it’s only seethru in the first path, not the bounces. but… that’s a lot of noise and random raytraces thru polygons. not very efficient, i think. in a gaming scenerio you don’t need this kind of precision, anyway. imo
I understand how it should look, I mean that for me it stopped working on 5.3.1. It works on 5.2.
Lumen already supports dithered translucency in way with distance field reflections, I wonder if there’d be a way to hook the proper components up. Dithered translucency always seemed like a very smart solution to transparency (NVIDIA had a groundbreaking paper on stochastic transparency), and I’m sad it never really took off by and large.
A good sample of gamers hate dithered masked objects.
Unreal is famous for it. Hence why so many UE games force TAA.
Which again, people hate forced TAA and hate games that depend on them.
I know I’m being redundant but know one else will stand up for players against TAA on this thread.
@jblackwell
Unreal is years behind translucency. Ever heard of deferred texturing?
It’s what allowed the PS4 and PS5 to display the massive forest(translucent grass etc) in Horizon forbidden west at crispy native resolution.
brilliant would be if it’d dither in the reflection too
Lumen reflections use temporal jittering which means the jitter in the reflections should reconstruct the dithered object in the reflection no?
Dithered translucency always seemed like a very smart
This might be true if temporally dithered effects didn’t require the entire image to be smeared in motion/basic gameplay because temporal filter(DLAA, TAA, etc) dependendency.
A smarter way to use dithering effects would to have a material that leaves 2 frame trail across the g-buffer. Basically do what TAA does but on a per object instance.
Lol
All this talk about reflecting translucent materials made me think to test how SLW is working these days. I figured it being technically opaque may make it a good substitute for glass in some cases.
Long story short screen tracing is having issues with SLW.
Single layer water does not receive perspective correct screen traced reflections, presumably due to having its own separate depth pass. Instead, it will be projected onto the depth of whatever opaque surface exists instead.
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i gotta be blunt and say, idgaf what gamers think. they get fed a new meta whenever youtubers or tech companies throw up a new buzzword. i think taa still looks good. the stability on dithered objects is not always there, but if it’s dialed in well there are not alot of artefacts. this dithered glass hack for sure is on the edge of what looks good. taa handles it fairly well tho. if it’s needed, it’s there for testing, how good you can make it look.
That is strange. It makes sense as you lay it out, but I was having SSR issues with SLW a while ago, and I just couldn’t figure out the cause, good work.
Something I’m trying to figure out with regards to water reflections: in testing 5.3, I discovered that liquid niagara fluids are now actually present in the lumen scene, with the water surface represented opaquely by what I believe is the albedo of the water. Strangely enough however, the water rendering system still doesn’t appear in the lumen scene.
This is very confusing imo, because the fact that epic got a volumetric fluid simulation to show up in their lighting cache, but not a tesselated sheet or heightfield, is interesting from a development perspective. Although I have no doubt you could art the problem away, it’s strange to have screen traces cast such strong GI from water without any fallback.
As of about four hours ago. It’s amazing how much improved lumen is to RTGI on scalability and quality.
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Hello, we found the issue with reflections in 5.3.1 - We use Lumen Reflections with RayTracing Reflections Enabled when available.
To explain better, I created this simple scene using Engine Water Ocean, Simple meshes and materials from the Engine folder. No post-process involved.
The example scene (as well as our original project) is created in 5.2.1. and opened in 5.3.1. later on.
5.2.1 has no glitches:
5.3.1 shows a glitch in water reflection which is annoying when you have many objects around the water area.
More examples on drive https://drive.google.com/drive/folders/1oMFA3lAuvLykfpq4i7K0s18UFKIwYVy0?usp=sharing
Can you advise please?
Many thanks!!!
Came in two days ago, curious what it means by translucent materials in lumen not casting shadows, as I wasn’t aware lumen supported any translucency at all.
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I think translucent materials were always projecting shadows (just opaque) when ray traced. Maybe they just disabled them by default to be more in pair with Lumen, which does not cast them.
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NvRTX Caustics has this function implemented: https://github.com/NvRTX/UnrealEngine/tree/NvRTX_Caustics-5.2
Are you seeing any obvious screen-space artifacts? I can’t really tell in that photo if it’s the lumen scene or not, but if refraction now supports lumen that is a game-changer. That’s actual refraction available in real-time.
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RT translucency and refraction was definitely on (notice the inverted refraction in the full bottle compared to the empty one). No artifacts besides the limited trace distance (notice the distant terrain is missing in the full bottle). There is now a cvar for showing GI and emissives under ray traced translucency. Separate options for reflection vs translucent.
I think it was on by default for translucent, but off for reflections. But when I enabled it for translucent reflections, they also began to show indirect lighting.
It definitely seems lower resolution than elsewhere, because I did get some light leaking. Not sure if it’s lumen being sampled though, or something else (like a dedicated low res RTGI).
Regardless of how it is done, RT translucency with refraction can indeed now be integrated into scenes using Lumen with much more visual consistency.
I’d still use rastered translucent for anything that doesn’t require refraction, since there is a visible decrease in GI quality when viewed through RT translucency. But for use cases like highly refractive objects it is not noticeable, and artifact free - unlike screen space refraction.
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Very cool! Is this as of 5.3, or main?
It’s sampling Lumen Translucency Volume, same one which is used for GI on translucencies. And indeed it’s lower quality than what we use for opaque stuff. Idea is to switch at some point to single layer refraction, similar as we do with single layer reflection.
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Not available on 5.3 I take it? I just tried to replicate @BananableOffense 's work and it appears to be the same light-leaking RT translucency.