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Question about VR

Open xMorioh opened this issue 1 year ago • 2 comments

Hello there,

i am wondering if there is a proper way to setup PresentMon either CLI or GUI for VR.

As far as i know any VR game will display inside the VR Headset but also inside a Window on your PC Monitor which is a capture from the games VR eye render either left or right eye depending on the game.

In my Theory at least i think it is not simply possible to capture the Window since it perhaps gets VSync with tripple buffering forced on from Windows OS ?!

So would i need to overlay the GUI to the VR Headsets Display_s_ or is there perhaps a better way ? or can i perhaps get at least some reliable data with the Windowed display like GPU/CPU wait/busy but no proper Display Latency data ?

Would be great to hear back from you guys, and thank you for the great tool :)

xMorioh avatar Apr 05 '24 19:04 xMorioh

The short answer is no, this isn't properly supported.

If you target the game process and monitor window, that should work and might be useful as a first level of analysis.

However, it will miss any extra latency to display on the HMD. I think it will also miss any cpu/gpu cost associated with final warping which IIRC is done on a separate process.

I guess there is also the concern of VR reprojection, motion smoothing and a whole bunch of other VR specific things in the end that would interfere with proper data readouts.

So it's probably best to check if the game does have a non VR mode and test the games performance itself this way instead, leaving VR rendering out of the equation.

Well this pretty much answered my question, thank you :)

xMorioh avatar Apr 06 '24 10:04 xMorioh