Does RTX ray-traced Global Illumination always produce noise?

[I Create Art!]

Hi, I'm considering buying a RTX card for 1 reason only, I am tired of building lighting & I never want to press that button again, I know that soft shadows are working but from everything I have seen so far real time global illumination is very noisy and its not yet ready, I have watched videos of the hybrid solution but that will require building lighting right?

Anyway I've never tried it so I dont actually know what state its in, so my question is does RTX ray-traced Global Illumination always produce noise, or is that just the path tracer?

[darthviper107]

Raytracing will have noise, that's why there's the denoiser, most likely if you still see noise then you can increase the quality settings at a cost of performance.

[Frenetic Pony]

Yes, and also you will still need to build lighting, even with an RTX card.

The good news is, at some point maybe this year you'll have a preview lighting button that gives you an accurate preview of baked lighting of whatever you're pointing the camera at right now. So workflow will be much easier, and the lightbaker is being re-written too, to be much faster and give better results. But that's not coming till 4.23 at the very earliest, so I'd consider waiting for now, see how backporting DXR to older cards goes or what AMD comes up with 2 months from now. Buying an expensive RTX card right at this moment won't give you what you're looking for yet.

[Tim Hobson]

For game development purposes, shadows and AO makes the most sense for performance reasons. Reflections can be expensive, but are manageable depending on your target hardware. Currently Translucency and RTGI are disabled by default and considered experimental since they still require additional work. That shouldn't stop you from enabling them, testing them out, but they aren't production-ready for games.

[darthviper107]

Yes, and also you will still need to build lighting, even with an RTX card.

The good news is, at some point maybe this year you'll have a preview lighting button that gives you an accurate preview of baked lighting of whatever you're pointing the camera at right now. So workflow will be much easier, and the lightbaker is being re-written too, to be much faster and give better results. But that's not coming till 4.23 at the very earliest, so I'd consider waiting for now, see how backporting DXR to older cards goes or what AMD comes up with 2 months from now. Buying an expensive RTX card right at this moment won't give you what you're looking for yet.

Using raytracing does not require lightmaps, it's designed to be real-time. In the future the editor will likely be able to utilize raytracing cards for lightmap baking. For right now, it's mostly going to be useful for people to make quick high quality renders for images or video, most users don't have capable graphics cards so you can't just switch over to raytracing entirely at this time.

[SonKim]

I think archviz people well love the ray tracing stuff especially for rendering stills images, the fps merely drops to 5. You can see an example of 3 bounce of GI and 20 spp using RTGI. Kudos to the rendering team, you guys are my heroes!

PS> Everything is real-time in the image, NO BAKING.

[Frenetic Pony]

I think archviz people well love the ray tracing stuff especially for rendering stills images, the fps merely drops to 5. You can see an example of 3 bounce of GI and 20 spp using RTGI. Kudos to the rendering team, you guys are my heroes!

PS> Everything is real-time in the image, NO BAKING.

Yeah this should be mentioned, if it's just stills you're looking for then raytracing might indeed be what you're looking for at the moment.

[William K]

I think archviz people well love the ray tracing stuff especially for rendering stills images, the fps merely drops to 5. You can see an example of 3 bounce of GI and 20 spp using RTGI. Kudos to the rendering team, you guys are my heroes!

PS> Everything is real-time in the image, NO BAKING.

whats the point when they wont look half as good as an offline renderer and the 5 fps minus wont run it in realtime then why in the world would you use ue raytracing for this especially when pgotorealism is everything in archviz.

[ZacD]

Because realism isn't everything?

People have been using game engines for interactive arch vis and for film/video work long before they were even remotely realistic.

And you can now easily compare a path traced render to the ray traced version.

[SonKim]

whats the point when they wont look half as good as an offline renderer and the 5 fps minus wont run it in realtime then why in the world would you use ue raytracing for this especially when pgotorealism is everything in archviz.

You know you can output render passes from UE4 and comp it to make it look better? It's still a viable workflow compare to dealing with lightmass issue and long render times. The quality and speed of the RTGI will only get better!

I'm working on a new scene, lets see how far I can take it.

[I Create Art!]

I think I may go for the cheap GTX 1060 For now just to check it out the DXR features since I need to replace my current GPU, later in year I'll probably get a RTX 2080 Laptop. But I hear RTGI is the most expensive feature with games like Metro Exodus running at 9fps average at max settings on 1440p resolution on GTX 1060, but that's not so terrible for testing.