Hopefully Lumen works for foliage. All UE5 demos intentionally avoid foliage, but in the real world, the majority of games have dense foliage nowadays. Trees, grass, you name it.
SVOGI did it perfectly, you can see how beautiful forests look in Kingdom come: deliverance and it was extremely fast. Hopefully lumen isn’t worse than something almost a decade old.
If lumen doesn’t work with foliage, it’ll be a major limitation.
I could experience some weirdness when not looking at it, it stops using the light information and all GI becomes “dark”, I don’t know if it was expected
And also it “ghosts” all background as they were illuminated by the light source
Also in the same scene, I got a drop of 50% of the FPS with Lumen enabled:
UE4:
UE5:
What about stereo support for VR? I know performance is nowhere ready for VR framerate requirements, but I’m just talking about the ability to test it out. From a technical, not performance standpoint, will VR be enabled in 5.0, or will I just see Lumen out of one eye?
Yeah, I could totally see the VR performance not being an issue anymore in 2 years or so, specially with upscaling technologies and foveated rendering.
We experimented with EA but had to use fake lighting for this cinematic.
Ray Traced Reflections are deprecated and generally don’t integrate properly with many of the engine’s features, like translucency and skylight. We are only developing Lumen Reflections going forward.
Clear chrome/mirror material reflections look blurry for some reason. In Early Access Lumen reflections looked a bit sharper. But in both versions (Early Access and Preview) Lumen reflections look very splotchy.
Thanks for pointing this out, we will investigate. There’s no reason that a mirror reflection on an opaque material should look blurry with Lumen Reflections using Hardware Ray Tracing.
Will there be an update for double-sided surfaces and foliages?
The Two Sided Foliage shading model support from Lumen GI didn’t make it into Preview 1, but will be in Release 5.0, and this makes foliage look much brighter.
Currently, Landscape grass types and painted foliages do not seem to support Lumen.
For a foliage type to cause occlusion you have to enable ‘Affect Distance Field Lighting’ on the Foliage Type. It’s off by default to avoid destroying performance with high instance counts like grass, but should be enabled on bushes and trees.
Lumen does not seem stable in natural environments.
This is very concerning, can you give me more information on when that happens, or a video of what it looks like? A project to reproduce it would be even better. I will test in some heavy foliage scenes and see what I can find.
I don’t expect Lumen Reflections to match Reflection Captures (one is offline and the other is realtime) but it should look much better than that. I will investigate what is happening to lose the normal detail on metals, thanks for pointing that out and the screenshots to demonstrate.
Yes, that’s what we have at this time. It supports glossy reflections only and cannot provide mirror reflections. It also leaks through walls within 2 meters.
That is not expected. First, check the Lumen Surface Cache viewmode to make sure those areas have Surface Cache coverage. If those walls have coverage, then it is most likely the issue described here.
And also it “ghosts” all background as they were illuminated by the light source
This is caused by Screen Traces picking up translucency in the foreground. We don’t currently have a solution but will be working on it in the future.
Also in the same scene, I got a drop of 50% of the FPS with Lumen enabled:
You should expect an fps drop when enabling dynamic GI, it costs something. If you drop down the Global Illumination scalability to Medium, Lumen GI will be disabled, for GPU’s that can’t afford it.
We don’t support VR or splitscreen yet for 5.0. Splitscreen will be in a future release, however it’s uncertain whether we can make a version of Lumen fast enough for VR requirements.
This is very concerning, can you give me more information on when that happens, or a video of what it looks like? A project to reproduce it would be even better. I will test in some heavy foliage scenes and see what I can find.
I can send you the “Beech Forest” scene. Please send me your contact information via private message.
For some reason, with Hardware Raytracing enabled, Surface Cache reflections look fine but switching to Hit Lighting the Skylight illuminates an interior scene very brightly (as if it was an outdoor scene) and there’s no GI in the reflections. This scene is using a Sky Atmosphere with Real Time Capture enabled. With Real Time disabled and Hit Lighting enabled, the environment looks better (not as good as with Surface Cache and Real Time Capture) but the reflections still have no GI.
Surface Cache:
Hit Lighting (Real Time Capture SkyLight ON):
Hit Lighting (Real Time Capture SkyLight OFF):
but switching to Hit Lighting the Skylight illuminates an interior scene very brightly
Good catch, that one will be fixed in Release 5.0. There were several other issues with Hit Lighting preventing it from being the higher quality reflections that it’s supposed to be.
Thank you for your response!
Re translucency mode - if Ray Tracing is depreciated feature from now on, does it mean that we should always use Raster type in translucency setting rather than Ray Tracing?
Because at the moment it seems that despite of Reflection issues Refraction looks much more realistic when Translucency set to Ray Tracing. In Raster mode Refraction doesn’t look as realistic in addition to very lowres and blurry reflections.
Thanks
Thank you again for opening this space for feedback @
I found a small “issue” regarding Lumen GI and Stationary SkyLight, it seems both aren’t compatible. All my SkyLights were Stationary, and when I disable Lumen GI through Scalability, my Skylight stops working and becomes black, but it works if I set to Movable.
It happens the same during runtime:
I’m not sure if Stationary SkyLights were changed, before using Movable was making the shadows being “grayish”, but now using Movable seems fine, which makes this whole “issue” not a big problem because I can just use Movable again, but anyway I don’t know if it was supposed to happen.
top ue5 preview 5.0 launcher version
bottom ue5 preview 5.0 source code version build with win 11 sdk
both using same project same level same setting (windows 11)
why launcher is ugly and source code is good ?
First of all excuse my poor english…
After testing and old Archviz EA2 project in Preview version, all I can say is that you are doing an amazing job.
We spend an incredible amount of time dealing with different problems in early access and after opening the level in Preview version the improvement is incredible.
Preview is far from perfect but it is great to see this huge evolution.
We tested unreal 5 just for archviz videos with RTX3090 and framerate was not taken in account.
All we wanted to know was if Lumen could be used for archviz instead of baking… It´s close, pretty close.
Hit lightning for reflections was not working properly so we had to use surface cache.
GI is much better in Preview.
Reflections and translucent materials need some more work, as we all know, but it´s fair to say that you are changing the game and making a lot of lifes easier. At least mine.
We all want a final product as soon as possible and most times we forget to give you the credit you desserve for this amazing software.
Reflections fixed / improved means no more baking for us, with little to no noticeable quality difference.
With Lumen we can show our clients the evolution of our designs with a great quality and 10 times faster than baking light.
Thanks for your work .
Re translucency mode - if Ray Tracing is depreciated feature from now on, does it mean that we should always use Raster type in translucency setting rather than Ray Tracing?
Sorry I was saying Ray Traced Reflections are deprecated, not Ray Traced Translucency.
Ray Traced Translucency doesn’t yet work together with Lumen GI, so you’ll get unshadowed skylight. That’s something we hope to improve, but it will be a long way out.
