I'm sure post-process shaders can be written to take the shutter vision into two separated viewports for some of them.

There's already DOSCulus around, but I don't think it emulates any headsets on the DOS side, it just displays non-stereoscopic copies of the DOS framebuffer in each eye of the Rift. It'd be a good starting point though.

It's worth noting the Oculus Rift & other modern headsets have significantly different eye geometry compared to older ones like the VFX-1. The VFX geometry is "flat" but the FOV is narrow enough it doesn't matter. The Rift uses barrel distortion, which would have to be added in post, to achieve a much wider FOV (I only have a Rift DK1 but I imagine every other current headset is similar.) The eye spacing is also way different. To make a VFX-1 game compatible with the Rift you'd have to chop the image down the middle and move the left & right eyes farther apart.

There's only one game I know of that supports both the Oculus Rift (DK1) and the Forte VFX-1 natively; it's called Gridfighter 3D and I wrote it. 😜 The Rift & VFX-1 render paths are exactly the same, but all of the eye geometry is variable, so I just moved the center & boundaries of each eye-image to the right place. I didn't do any barrel distortion on the Rift but I kept the FOV narrow so it looks fine. (Try starting the game in VFX-1 mode using a Rift and you'll see the problem.)

That issue seems similar to the triple-monitor support in DOOM : https://www.youtube.com/watch?v=s2TG7VCms3Q

You can see distortions in the walls near the seams, as if there was insufficient overlapping done.

Kind of, but it's not a matter of overlap - It's a necessity of projecting a 3D playfield onto a 2D surface (which then gets converted back to 3D by your brain.) It's the same reason wide-angle cameras (GoPro, etc.) take 'fish-eye' photos, because they're taken on a flat CCD & you view them on a flat display afterwards.

The distortion is minimized around the center of the display, so if you shrink the FOV down enough, a flat projection looks fine. The VFX-1 only has a ~45 deg. FOV; the stereo 3D effect works great but it's like looking at the world through a window (or a really bulky racing helmet.)

If you don't try to increase the FOV and just keep it at what a '90s headset would offer, you can totally get away with a flat projection on the Rift. But you'd still have to slice the image in half and move the eye centers into the right position. Not an insurmountable problem at all.

Great Hierophant wrote:

That issue seems similar to the triple-monitor support in DOOM : https://www.youtube.com/watch?v=s2TG7VCms3Q

You can see distortions in the walls near the seams, as if there was insufficient overlapping done.

That's probably due to Doom viewing angle been 90 degrees from each screen, which in real life doesn't really work

I came here with optimism looking for info on current modern VR headset working with older Dos games (System Shock, Doom, Dark Forces, Magic Carpet, etc)

I understand you won't get true VR but I was hoping for really good 3D stereoscopic effect.

I see or can find bits and pieces around the web (DOSculus, GZ3Doom, vorpX-DirectX only) but full info seems incomplete.

Since most run great with Dosbox, is there anyone working on a Dosbox version to work with many of the market VR headsets?
Or links or info of the like?

Thanks.

Good question, I wonder the same. As far as I know, some games/applications used a VESA-like middleware (3D BIOS ?) to interface with various VR glasses,
so it shouldn't be too hard to support that as well. Alternatively, it could be possible to use old VR glasses with an RS-232 cable in DOSBox.
(Provided, that someone still has a CRT monitor and that these shutter glass "tricks" on VGA work from within DOSBox/the host OS.)

Edit: Name of that driver/API was "LCDBios". See http://www.stereo3d.com/driverc.htm
Edit: That page is interesting, IMHO. Among other things, it also has a comparison table of old HMDs. Alas, it is dated also (~2004 ?)