Currently, Lumen does not appear to function completely with Forward Rendering and produces quite a lot of artifacting. Will this be addressed?
I do honestly hope so because it would make for quite an amazing VR experience
Nope for VR Lumen | Inside Unreal - YouTube
And nope for Forward Rendering. Same video, but I don’t have the timestamp.
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What is the state of lumen + forward rendering in 2024?
No plans for lumen with forward rendering, from what I can tell it’s just too complex from a pipeline perspective and too few users. There is now lumen for deferred on mobile though.
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I think as an addition to my previous comment: lumen is designed as an orthagonal feature to VSMs and especially nanite, and since nanite is by definition a deferred renderer, they pretty much all have to be. As mobile deferred rendering has become possible with memory bandwidth going up, I sort of wonder if forward rendering will just end up becoming deprecated from UE5 at some point in the next few years.
Quite a few people have actually gotten lumen working with VR, albeit with quite high system requirements.
For those unfamiliar with it, VR is normally rendered forward-shaded because forward shading in UE has a lesser base cost and doesn’t require all the large render targets that deferred rendering does, a consideration very important on a machine that is often very constrained and has to spit out a large resolution very fast.
I’ve seen a handful of people get the full UE5 featureset up and running on VR, including lumen, nanite, VSMs, and more. VR doesn’t need to be forward-rendered, it just is because it’s cheaper.
I have tried deferred rendering for VR but even for simple scene’s you loose a lot of performance. The people who get it running in VR usually run it at 45fps and rely on Oculus Asynchronous SpaceWarp to make it 90fps.
You also loose anti-aliasing because TAA or TSR degrades motion clarity, this is usually not a problem on desktop but it is in VR as the pixel size is bigger and the ghosting is pretty noticeable. With forward rendering you have access to MSAA which makes the image nice and crisp.
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This is quite concerning because at the rate things are added and deprecated, what engine version are VR developers supposed to be using?
I set up a small, very simple project with Groom plugin hair, lumen, forward rendering, MSAA. From the project settings there is 0 ways to see what options conflict. I can’t tell what works and what does not until I run into issues. I figured out the hairs of Groom glitch horribly when using MSAA. So basically nothing what I had in mind can be combined in one project and VR seems out of the question.
Well… Downgrading seems out of the question as well since EPIC has no LTS plans. I’m getting sick of this. This goes straight into the garbage bin. What other modern games are doing (RE, Horizon, etc) seems just 100% broken and nonexisting combined in unreal.
What I heard from people in VR communities (SkyrimVR is a big one) is that low FPS makes the game entirely unplayable for them because they end up with reprojection.
So did it get to the point where the engine is simply unusable for anyone?