[Gear VR] Vulkan API support soon ?

My guess is that until all S6 phones get N support, Vulkan support isn't coming. In USA, T-Mobile is still lacking N support for S6 (still listed as "under development").

On top of that Android 7 is a performance hog, so S6 + Android 7 + Vulkan might run similarly to S6 + Android 6 without Vulkan. Plus on top of that Android 7 is plagued with issues on Gear VR (vertical tearing, etc.)

I just saw in the news that T-Mobile Galaxy S6 is finally getting Android 7. My guess is that it will complete the line up of Gear VR devices running Android 7.

Well, now I have a choice to either update to Android 7 or keep postponing the update. I'd really like to know whether Vulkan support is coming soon to Gear VR. I don't want to update to Android 7 just to end up in the world of pain (VR performance wise).

vrdaveb said:

Google's compositor works differently from Gear VR's and they don't necessarily have to wait for front buffer access and multiple queues to arrive.

Just curious, but what does Gear VR's compositor do differently vs. Google's that FB access and multiple queues are required? Is it related to a feature exclusive to Gear VR?

@imperativity

Any news in this department ? Will Oculus Go run mobile Vulkan ? (with support for UE4)

@imperativity 

motorsep said:

@imperativity

Any news in this department ? Will Oculus Go run mobile Vulkan ? (with support for UE4)

Very interesting in this too!

So, this happened: https://arstechnica.com/gadgets/2018/03/vulkan-1-1-adds-multi-gpu-directx-compatibility-as-khronos-looks-to-the-future/

I really hope Oculus Go will have support for Vulkan out of the box and UE4 would be able to provide support for Go with Vulkan.

@motorsep

I'm hopeful, but the release notes are kind of vague. There are two features Vulkan needs to support for Gear VR rendering to work: front buffer rendering & multiple queues with different priorities (link to OC3 talk source). If anyone more knowledgeable can give us confirmation that these are part of Vulkan 1.1, that would be a huge milestone for seeing API support in Gear VR.

However, I very highly doubt that it will ship in time for Go's launch. Qualcomm still needs to provide a patch for SD821, then Oculus would need to release updates to both their native SDK as well as (more importantly) Unity & UE4 integrations. We'd also inevitably be faced with lots of issues when using Vulkan in Gear VR, even if we solely targeted Go. It's the integration I'm the least confident in TBH; they can't even give us bug-free stereo overlays/compositor layers, as expressed multiple times by @Norman3D.

I no longer expect Vulkan to be a big player in Gear VR in the immediate (<1 year) future of game development. It's an even bigger undertaking than Multiview, even without the carrier factor on Go. What I'm much more excited for is @rpalandri's scaled bin multi-resolution rendering. Qualcomm already has an extension for it - they were the ones to suggest it to Oculus - and devs can turn it on practically with a flag in the manifest. It has the potential to render the center of the screen at panel limited resolutions (1.5x/1536px) at much lower than the existing 2.25x rendering cost.

@firagabird Well, UE4 has no forward ES3.1 support for Go/Gear VR, which means I can't use ASTC compression for mobile VR. Plus Vulkan would reduce drawcalls by much (at least that's what it does on PC). So IMO Vulkan is essential for UE4 mobile VR devs (in part because Epic isn't going to implement forward path for ES3.1 and ES3.1 doesn't solve drawcalls overhead).

motorsep said:

UE4 has no forward ES3.1 support for Go/Gear VR, which means I can't use ASTC compression for mobile VR.

This reinforces my point. UE4 has bigger concerns than implementing brand new features/integrations. ES3.1 support with forward rendering should be a hassle-free setup, and yet your experience shows otherwise. If the engine devs can't fix such vital aspects of the mobile VR dev's workflow, what do you think will happen when they try adding an additional complexity with Vulkan support?

I'm not saying Vulkan isn't huge for Gear VR; it absolutely is. However, I'd much rather have all of the Mobile SDK's existing features accessible in both the big engines without major issues. Plus, Vulkan support in UE4 is hardly essential to make incredible games for the platform. Just look at Daedalus, Witchblood, or Face Your Fears, all built in UE4 and without Vulkan.

One last thing: According to @imperativity in this thread, forward rendering in ES3.1 should be working. If you have issues with it working, you should follow up with him as well as file a formal bug report. However, what's clear is that Epic did implement the forward path for ES3.1.