Mirroring the game output.

"atavener" wrote:
KuraIthys has basically covered it. But I'll add a note: a higher-resolution backbuffer will probably be desirable for quality anyway (if the framerate can be sustained) -- a low-res distorted resampling of a low-res source is part of why we see such bad pixelation and unreadable text. A higher res source, and sharper sampling than bilinear helps.

Anyway, my point is that we might have a higher resolution backbuffer to present, and not need to render a third view for a monitor.

However there are some advantages to a third render: using a lower FOV suitable for monitors, and possibly different perspective -- depending on whether you're imagining the use being demoing Rift to outside observers or making a game pleasant to watch for an audience (a 3rd person perspective might be useful for this -- Alone In the Dark style or even chase-cam).

The issue with it wasn't all to do with resolution though. The main problem is actually the aspect ratio; Unless you plan on showing the view from both eyes, or leaving a large part of the screen blank, you now have a situation where you're trying to display an image with an 8:10 ratio, on a display that is probably 16:9, 16:10, or 4:3.

That's either going to leave much of the screen blank, or result in some really extreme stretching of the image.
Neither of which is really something you want to do...

"Marbas" wrote:
Not an engine coder at all. Not sure if Unity support running the game in a side by side monitor setup, otherwise it may be possible to work something out with render to texture or just copying one of the already existing renders to the "other side". Anyways, If not in unity maybe some other engines with rift support that also work well with side by side monitor setups. I dont think you are stuck to low level engine coding for such a display scheme to work. Would definitely be a great feature for those rift-drivers like Vireo to have.

The problem is, most game engines won't render to multiple physical displays, or even multiple windows!
Of course, that's not to say there wouldn't be any.
Unity in parficular may have implemented functionality for that just because it supports Wii U development (amongst other things) where 2 screens is the norm, rather than something unusual.

If the engine natively supports rendering to multiple displays and/or windows, then you can probably do it without huge low-level changes.
If not though, you'll have a really hard time with it, because any final image rendered would then not be something you can show on anything other than the 'main' display. (which would be the rift). Mirroring the rift output wouldn't help, because that's done at an even lower level which the engine has no control over...