Forward render w/ raytracing (4.23)

Engine fails to load on an empty project with Forward render and raytracing enabled.
Are these not intended to be used together?

Hey Richard !

Indeed, Raytracing is only supported with the Deferred Renderer and there is no current plans to support it on the Forward Renderer.

Thanks Antoine, good to know.

Really, no plans at all? Not even for ambient occlusion (something which currently cannot be used in forward in Unreal and is very much missed)?

Barring that, do you have any plans to make the raytracing denoiser work on your current ambient occlusion implementation (since it’s the ugly dithering that disqualifies ambient occlusion from being used in forward currently)?

I agree that having raytraced AO supported in forward would be great.

But, in theory you can use AO with forward currently, because since recently, SSAO in UE4 does support smoothing. You need to set r.AmbientOcclusion.Compute 1, and r.AmbientOcclusion.Compute.Smooth 1. That will smooth the SSAO output and remove the ugly dithering. Only problem is, there’s a bug currently that makes the engine crash when trying to use AO smoothing together with MSAA: Unreal Engine Issues and Bug Tracker (UE-80268). So currently, you can only use it if you aren’t using MSAA. That bug will hopefully be fixed in 4.24.

Thanks, that sounds good, but I think I’ll wait until there’s an actual UI for it.

Console commands in the Unreal Editor feel iffy… because how sticky are they really? Do they get saved? Where do they get saved? Can you see a list of commands you changed from the default value somewhere?

Hopefully what you describe will end up in the project preferences, or even better, post process volume settings (because usually, AO doesn’t just have smoothing on or off… there’s usually sampling levels and blur passes associated with it, that has a performance/quality balance you need to set).

Theres SSAO/Baked ao in forward already. Forward is pretty much vr only at this point.

Put them in Config/DefaultEngine.ini and you’re golden. That’s where the project settings window takes its values from and saves them to (most of them anyways).