Vive Tracker in Unreal

[thoeme77]

Hi all,

 

I was trying to create a mixed reality setup in Unreal Engine 4 using the HTC Vive Tracker to track the real world camera. But I stumpled upon a problem, which I wasn't able to solve by myself. 

While using the "Get Tracked Device Location and Orientation" node within Unreal I've realized that the output of the coordinate system is Y-up (Pitch, Yaw, Roll) instead of Z-up (Roll, Pitch, Yaw - used by Unreal)

Which led to the problem that when I was setting my virtual cameras orientation to the orientation of the tracker, that (depening on method I tried) always one or two axis were wrong/inverted. I've also tried both methods (just in case) for setting the world and relative orientation of the virtual camera to the trackers orientation.

 

Can you provide me with a method with which I'm able to convert the coordinate system in Blueprint or am I doing something completly wrong anyways? Or is it enough to reset the tracker after mounting it on the camera? (I wasn't able to test this myself because I found out how to do that today) 

[jpomichter]

I found a solution on the Unreal Forums. In your Tracker Blueprint, place a CombineRotators node in between your Get Tracked Device Position and Orientation node (or GetWorldRotation node)  and the SetRelativeLocationAndRotation (or SetRelativeRotation. Plug the return value from the Get node into the B input of the CombineRotators. set the A values as: X = 0, Y = 90, z = 0. Here's the link to the forum thread...

 

https://answers.unrealengine.com/questions/744900/htc-vive-tracker-in-unreal.html