AMD GPUs to get Ray Tracing turned on for Mesa 23.2

Great to see that the MESA devs are able to allow for Raytracing support. However i guess the "out of the box" support will still be limited to games that use Vulkan as the graphics API. For DirectX 12 titles running through proton one might still need to set a startup command to get Raytracing enabled. Performance is also still weak with MESA RADV when it comes to raytracing. The only game that is enjoyable with raytracing on my end is Doom eternal in 1080p. I am using an RX 6700 XT.

I have an RX 5700 (Not sure if XT), that means it does not have Ray Tracing cores, right? Would I lose a lot of performance if I were to enable it on a game? I mainly want to play Cyberpunk with it.

Quoting: ripper81358Great to see that the MESA devs are able to allow for Raytracing support. However i guess the "out of the box" support will still be limited to games that use Vulkan as the graphics API.

Shouldn't be since it worked for Control which is DX12.


Last edited by Liam Dawe on 14 June 2023 at 8:35 pm UTC

Quoting: ripper81358For DirectX 12 titles running through proton one might still need to set a startup command to get Raytracing enabled.

Why would Valve limit this on their end now that it "just works" if they're the ones pushing forward a lot of this upstream development effort in the first place?

Proton Experimental is usually ready around the time the upstream features land, unless the Wine/Proton bits that need to be developed are particularly complicated...

...and where DX12 is involved, this development falls in the VKD3D lib, which translates DX12 to Vulkan and iirc has been very busy with RT already (after all the features where already around to use, just hidden behind flags)

for now it's hidden behing a flag in upstream VKD3D, but Valve can patch the copy shipped with proton or pass the flag automatically
https://github.com/HansKristian-Work/vkd3d-proton/releases

QuoteVKD3D_CONFIG=dxr now enables DXR 1.1 as well. dxr11 is kept for compat
[...]
NOTE: VKD3D_CONFIG=dxr11 is required to enable DXR 1.1 for now.

and they clearly have DXR 1.1 available already, just not sure if with any missing bits


Last edited by Marlock on 14 June 2023 at 9:11 pm UTC

Quoting: ArehandoroI have an RX 5700 (Not sure if XT), that means it does not have Ray Tracing cores, right? Would I lose a lot of performance if I were to enable it on a game? I mainly want to play Cyberpunk with it.

if games with RT support get too heavy on your machine, you'll still be able to toggle RT off via in-game settings

and most likely the driver will get a flag to force-disable RT too, since it's such a resource hog, in case a game doesn't let you tweak it the nice way

you should test it and see what happens

Quoting: Marlock

Quoting: ArehandoroI have an RX 5700 (Not sure if XT), that means it does not have Ray Tracing cores, right? Would I lose a lot of performance if I were to enable it on a game? I mainly want to play Cyberpunk with it.

if games with RT support get too heavy on your machine, you'll still be able to toggle RT off via in-game settings

and most likely the driver will get a flag to force-disable RT too, since it's such a resource hog, in case a game doesn't let you tweak it the nice way

you should test it and see what happens

Since the RX 5000 series has no hardware support for raytracing and therefore no support for the needed Vulkan extensions raytracing will most likely be disabled on systems without compatible hardware. Cyberpunk is a very demanding game even with raytracing disabled. It is also one of the games that makes heavy use of raytracing once it is enabled. You are lucky if you can get the game running at good quality and performance without raytracing.

Managed to make CP2077 work with ray tracing without hangs thanks to help from vkd3d-proton developers. It was just an unusual prefix mess up with Wine-staging at some point dropping an invalid nvapi64.dll in there that messes up CP2077 on AMD.

Performance of ray tracing is still not usable without upscaling even on 7900 XTX, but at least it's a fun experiment.


Last edited by Shmerl on 15 June 2023 at 5:12 am UTC

Quoting: ripper81358It is also one of the games that makes heavy use of raytracing once it is enabled. You are lucky if you can get the game running at good quality and performance without raytracing.

I must be very lucky indeed... I can play it at ~60FPS, more settings in high that in medium, and at 1440p since launch day... :O

Quoting: ArehandoroI have an RX 5700 (Not sure if XT), that means it does not have Ray Tracing cores, right? Would I lose a lot of performance if I were to enable it on a game? I mainly want to play Cyberpunk with it.

Actually, you can emulate ray tracing on older card. Of course, performance is bad, but you can somehow make it playable using lower resolution + FSR.

https://linuxgamingcentral.com/posts/portal-rtx-playable-on-amd/

RT is a huge fraud and marketing BS of Ngreedia, forced into existence by corporate power alone.

It's like a car manufacturer claim they can make "flying" cars now that lift up to 10 CM above ground and charging a lot more for it because they got to this "technology" sooner than competition! 10 CM above ground is as much a "flying car" as amount of "RT" today in recent games. 4090 ($1600 BTW) runs 20 fps with "real" RT (Cyberoverhyped 2077 Path Tracing).

RT is absolutely not ready and needs YEARS more to be able to enter mainstream video cards. So far majority of RT games have terrible performance even outside "RT" scenes. RT so far has destroyed game optimization because devs will assume people will just turn on DLSS/FSR not knowing what even are these (they add blur to games particularly when you move around, as opposed to native rendering) so they would not optimize as much as before.