another non Win7 desktop app...

[CandidAstrius]

I'm sorta curious why none of the desktop apps being offered actually support Win7, what is it that makes it so difficult to include?

just did a quick search.

https://www.netmarketshare.com/operating-system-market-share.aspx?qprid=10&qpcustomd=0

and Win7 still accounts for 47% of all desktop OS's

Would absolutely love to use one of these programs, and i know, one day in the distant future, MS will figure out how to finally force the upgrade allowing me too use this or one of the other ones, ( perhaps the new gen hardware requirement, but having just upgraded my box, I'm not going to have to worry about that for a year or two.) But in the meantime, i'm stuck using this lame old flat non VR screen for the majority of my desktop needs...

[Rishar]

*Not a Dev*

The biggest issue seems to be the API that's used isn't in Windows 7. It was introduced in Windows 8. WDDM 2.0. With Windows 7, you don't get a lag free experience and requires a lot more effort to program it for. It's not that it's impossible, but it would basically require them to have a seperate team working on just Windows 7 as it's a completely different beast to make this work with and probably still won't work as well.

A dev from BigScreen
"You see your desktop inside BigScreen instantly, with no lag/latency, at perfect framerate, with low performance cost. To achieve this, we use new APIs in WDDM 2.0 available only on Windows 8 and 10. Supporting Windows 7 requires more engineering effort and that screen would look laggy, and lower fps. We might still add support in the future, or at least let Windows 7 users look around in BigScreen and watch other people's screens."

Virtual Desktop is a good example. It *does* run on Windows 7. But it's a bit laggy in the process. Not to mention that MS is locking their Hololens to Windows 10 and AMD's/Intel's new CPU's. The only real option is to upgrade or...fall behind. And I think more and more we're going to see VR games only support Windows 8/10 and eventually, only 10.

[MyDream]

Rishar is absolutely correct. The low overhead screen grabbing API (called Desktop Duplication) was introduced with Windows 8.

It is not without downsides, though. For example it captures the screen at the refresh rate of the monitor (eg 60 Hz), while the HMDs run at 90 Hz. To work around this, we hook into running DX games and capture them at 90 Hz manually.

The Windows 7 desktop compositor can be hooked into too, and we have prototyped it, but there are some subtle problems with it. Since we are just 2 developers working on Light, we decided to focus more on the room simulator aspect.

[Rishar]

Since it captures at 90Hz, would it work better if you have a 144Hz monitor then?

[MyDream]

During DX9 or 11 gaming, Light captures at the HMD rate, so the monitor refresh doesn't matter. During regular desktop navigation though, a faster monitor would indeed make the experience a bit better.