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HTC Vive camera projection / alignment

Hey guys,
I’m currently working on my HTC Vive camera integration and I’m facing some kind of camera alignment problem.

The problem:
I grap the camera frames of my HTC Vive via “OpenVR” / “VR Expansion Plugin” and project it via a dynamic material on a plane.
This plane floats 100 units in front of my camera. See here:

https://forums.unrealengine.com/filedata/fetch?filedataid=121828&type=thumb

Now you can see, that there is a huge gap between the real and the pretended position of my controller in the image:

https://forums.unrealengine.com/filedata/fetch?filedataid=121830&type=thumb

Wanted behavior:
Valve managed to build a really good solution for it (you can see this in SteamVR). Both controllers are nearly perfect aligned to the image.
They use a some kind of concave plane (instead of a flat one) for the projection.

https://forums.unrealengine.com/filedata/fetch?filedataid=121829&type=thumb

My Questions:
Maybe I’m a bit naiv, but I guess that I can solve this problem properly if I know the following specs:

  • The distance / height I have to put my projection plane (in relation to my camera)
  • The width, height and bending parameter for the concave plane.
  • Valve’s OpenVR API offers three kind of camera images: distorted, undistortedand and maximum undistorted
    Will it be enough to grap one of those images or do I have to make a manual distortion with the image?

Thank you guys!!! :slight_smile:

Links:
OpenVR: https://github.com/ValveSoftware/openvr
VR Expansion Plugin: https://forums.unrealengine.com/development-discussion/vr-ar-development/89050-vr-expansion-plugin