Valve's GDC15 talk


I really enjoyed Valve’s chat at GDC on Advanced VR Rendering (GDC Vault - Advanced VR Rendering) by Alex Vlachos.

He mentions quite a few points which i took notice of and wanted to know if they were being implemented into Unreal 4.

We have the reprojection/timewarp already but Alex talks about Stenciling out and not rendering parts in the ‘overscan’ area to save processing time. He also talks about Normal maps in DXT5 and more interestingly, the normal mips being done in a better way to help with glossiness in minification scenarios.

Are any of these common to the development track for Unreal 4 ?

I understand the priority is not in VR at the moment, but is there a roadmap for specifically VR-benefiting developments ?

There’s another thread about getting distance-field raytraced shadows fixed which will be great and SLI rendering per eye sounds great in DX12 but I’d love to hear more from the UE4 team.

Thanks !

Matt Hermans

Seconded, excellent talk, amazing some of the performance gains being made (and others potentially yet to be discovered): 30% combined fps boost for those two seemingly (haha) straightforward techniques (“running start” and stencil mesh) would be a god-send.

I don’t doubt much of this will end up in UE4 in due time, if nothing else when UE4 reaches the inevitable point of supporting SteamVR / OpenVR (since Vlachos notes that all the above is included therein). Though from what I understand Oculus doesn’t plan to support OpenVR, so a little more heavy lifting may be required to get these optimizations implemented in Oculus Rift / GearVR games. But then as a layperson I don’t know what of this is better implemented in the VR hardware SDK, or in the game engine itself…

Can any Epic devs shed some insight? Thanks in advance!

Thanks for the reply !

I’d love to hear from the devs too as a lot of the VR engine conversations from Oculus is about their Unity integration. Other than them it’s Valve talking about their efforts but not much from Epic.

I’ve got a long history in the visual effects industry and I’ve played games all my life so this is a great time for me to cross over and bring my offline-heavy duty VFX methods to the real-time context of games and make VR experiences which bridge the gap.

Unreal was a big departure from the world of Maya/Max/Houdini but i’ve spent a heap of time figuring it all out but there’s an amazing lack of conversation/templates/roadmap from Epic despite them having such a capable engine.

Cheers !