# Oculus DK2 Rotation Problem

I’m doing a simple game-experience (simulation of tank) using Oculus DK2 and I have a problem with rotation. I want to use oculus rotation data to the rotation of the tank cannon in the Y-axis (horizontal rotation for cannon) and in the X-axis (raising and lowering the barrel). I noticed that as I turn Oculus only in the Y axis it also changes the value of the X axis which causes undesirable effect of lowering the barrel. I need synchronize cannon 1:1 with real Oculus rotation.
Can you advise me what should I do so that the X-axis value did not change with the rotation oculus in the Y-axis?

Thank You,
Raf

Can you post an example of the issue you are having?

The thing about rotations, especially ones that we try to keep continuous such as those rxyz in the Oculus Rift CHOP is that you can’t pull out the values on their own. They are a set of 3 values that represent a orientation. Just looking at RY doesn’t mean you will get the correct rotation because it also depends on the RX and RZ value to reach the final position.
For example a 90 degree rotation around Y is the same thing as a -90 rotation around Z followed by a 90 degree rotation around X. There is nothing saying the Oculus Rift CHOP will output 90 in RY in that case.
I think what you will want to do is put the orientation into a Null COMP and then pipe that into a Blend COMP and turn off the RX and RZ rotations there. That should give you a more proper Y rotation.
It’s also possible the rotation order you are using doesn’t line up with RX RY RZ that the Oculus Rift CHOP is outputting since you have a RX rotation inside a COMP that has RY applied (I’d have to check the order of operations there)

Thank you for your answer. Blend CHOP solution seems to be right, I check it out today. During the tests I noticed that, for example eyeL_21 channel seems to give rotations Oculus its axis regardless of the rotation of the other axes. I’ll check which of these solutions will be the most appropriate in this case.
Greetings

Hi, I am new to td and having this issues also. When you say ’ put the orientation into a Null COMP and then pipe that into a Blend COMP and turn off the RX and RZ rotations there.’

Is that put the rx, ry, rz into a null COMP’s rotations, then pipe that to a Blend COMP, and toggle the mask buttons to isolate RY? When I toggle any of mask buttons, I get no rotations at all. I am not sure how to work this Blend Comp. I’ve attached my attempt

And if it were working, how do I reference the output RY of the COMP in say a CHOP, like the blend CHOP? I havn’t found a tutorial on that yet