Classic Doom and the Oculus Rift

[Blastfrog]

I'm really hyped for Luckey Palmer/John Carmack's new VR headset, and want to get one as soon as I can afford it. But how do you think classic Doom would fare with it? Obviously, the game's default FOV of 90 degrees would be perfectly suited for it, but what about vertically? A rendered screen on Doom at max screenblocks would show 67.5 degrees vertically, but the Oculus Rift has a vertical FOV of 112.5 degrees. While rendering the view would be just fine, how about HUD graphics like the weapon? Those were 2D images that only took 67.5 degrees of vertical FOV into account. A crappy half-solution would be to use the extra cut off space of these graphics from the press release beta which took 89.1 degrees of vertical FOV into account, but that still doesn't account for the remaining bottom 11.7 degrees of screenspace.

Besides that, how would you render it, and would you take looking up and down into account? Would you use the easier to manage, but far less accurate OpenGL, or would you use the more traditional, "canon" software rendering? Personally, I'd prefer a new software renderer following the original's lighting model as close as possible. Basically a true color software renderer that uses raytracing instead of raycasting to manage lens distortion correction and view pitch far easier than you could with raycasting. This would allow the original lighting model to be used, as well as (arguably necessary) rendering quirks like sprites being able to bleed through flats to work properly as well.


What are your thoughts on this?

[fraggle]

Field of view isn't an issue - you just adjust the field of view vertically and horizontally to match the specs of the device.

As far as the renderer goes, I think an OpenGL renderer with the ability to properly look up and down is something that's going to be pretty much essential for this. The y-shearing trick works well enough if you're playing normally, but for a VR headset it's not going to cut it.

[kingbob]

You move around so fast in Doom, you are going to get some serious neck injuries if you use a VR headset.

[chungy]

Well as far as software rendering goes, it wouldn't be terribly horrible to do like Vavoom and steal Quake's renderer; but it'd be just equally as "impure". OpenGL rendering is fine in 99.98% of cases.

Largely Doom is such a fast-paced game (as kingbob said), that VR for it is probably not too feasible. Doom 3 (as John Carmack has already been porting) is better suited to it for being slower paced. I'm sure the weapons display/aiming is a whole lot easier to handle too.

[Blastfrog]

fraggle said:

Field of view isn't an issue - you just adjust the field of view vertically and horizontally to match the specs of the device.

Of course FOV isn't an issue with the world render, but my concern was about the "FOV" of the HUD graphics, namely weapons. The problem is that if you rendered them in their correct place, they'd get cut off. I mentioned using the beta version graphics which had extra space on them, but even then, it still doesn't cover the full view. Another issue is how far apart should the weapon graphics be spaced? I was thinking about 16 map units might be good, but I'm not sure.