Vulcan does not display Side-by-side VR, while OpenGL does

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Shade_N53
Posts: 2
Joined: Sun Jan 09, 2022 10:40 pm
Graphics Processor: nVidia with Vulkan support

Vulcan does not display Side-by-side VR, while OpenGL does

Post by Shade_N53 »

The problem. Side by side (aka SBS) is not displayed when Vulkan is selected. Crosshair is not in place in both Vulkan and OpenGL when VR options are not set to Normal.

The setup. I'm using Moonlight app to stream the game to my smartphone inserted into VR headpiece. I'm using GZDoom, tested this in earlier version and the newest, 4.7.1 (the output is the same).

Details. GZDoom supports SBS rendering with correct aspect ratio, currently set up in Options > Full Options Menu (OMG WHY?!!) > Display Options > OpenGL Options > Stereo 3D VR > 3D mode: Side-by-side Full. There are no other options to this render method, as far as I know.
Selecting OpenGL renderer at the starting dialog will display the correct render:
Spoiler:
Yet, if I use the more modern Vulkan renderer, it will only display one eye:
Spoiler:
which is obviously incorrect.
My concern is there are talks of OpenGL being dropped sometime in the future, so in newer versions I might lose access to this only VR option available. Perhaps there is something I can do to render SBS in Vulcan?

Also, the crosshair appears to be drawn much closer to the camera than most world objects, drastically reducing its visibility and usability overall: you have to aim between two blurry blobs instead of putting it on target. I don't know if there's a render distance option for it -- I haven't find any.

I don't know if it's a bug or I don't set up something right in GZDoom itself, so I'm posting this here. Any useful advice?
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Graf Zahl
Lead GZDoom+Raze Developer
Lead GZDoom+Raze Developer
Posts: 47988
Joined: Sat Jul 19, 2003 10:19 am
Location: Germany

Re: Vulcan does not display Side-by-side VR, while OpenGL do

Post by Graf Zahl »

The feature is not implemented in the Vulkan backend right now.
Shade_N53
Posts: 2
Joined: Sun Jan 09, 2022 10:40 pm
Graphics Processor: nVidia with Vulkan support

Re: Vulcan does not display Side-by-side VR, while OpenGL do

Post by Shade_N53 »

Graf Zahl wrote:The feature is not implemented in the Vulkan backend right now.
Oh, I see. Thanks for the quick reply.
And can something be done about the second part, the crosshairs being located too close in VR?

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