Hi all,

I've been working with Qt in conjunction with OpenVR in order to make an overlay for virtual reality. My understanding is that OpenVR runs the Qt application and requests that Qt render widgets to a texture that can then be displayed by OpenVR. It seems that some widgets in Qt, specifically QTableWidget, perform normally in a standard desktop application, but very poorly in virtual reality. A developer from OpenVR has suggested this may be an issue with the way that Qt renders widgets to texture.

For anyone that has access to an OpenVR-compatible headset like the HTC Vive or Oculus Rift, I've attached an archive containing source code and binaries (built both for desktop and VR) of a simple Qt application (created in Qt Creator) which implements a simple QTableWidget filled with 50 rows of simple data to demonstrate the difference in performance between desktop and VR applications. You should notice that in VR, application responsiveness drops significantly with noticeable lag when trying to interact with the application. Other elements such as QPushButtons and QLabels perform as expected in VR.

Thanks!

EDIT August 13, 2016: Issue seems linked to scrollbars in general. When using any widget that includes a scrollbar, I've noticed that performance drops whenever the scrollbar handle is anywhere other than the absolute top or bottom of the scrollbar. Adding to this, the hanging execution that occurs during this "lag" immediately ends if the user points the cursor outside of the Qt window in VR. I'm suspicious that the issue has something to do with input polling, as well.