Rotation problems

Troubleshooting General Help
1
  1. The below code rotates my camera node, but I assumed I would have to call cameraNode.setLocalRotation(vert); to rotate it, but I don't.


Quaternion vert = _cameraNode.getLocalRotation().fromAngleAxis(
             -FastMath.PI/_tank.getTurretElevation() , new Vector3f(1,0,0));



2)  I want to rotate in two directions at the same time but with this code it rotates only in the horizontal direction.

Quaternion vert = _cameraNode.getLocalRotation().fromAngleAxis(
             -FastMath.PI/_tank.getTurretElevation() , new Vector3f(1,0,0));
       
       Quaternion hor = _cameraNode.getLocalRotation().fromAngleAxis(
             FastMath.PI/_tank.getTurretHorizontal() , new Vector3f(0,1,0));

2

For your second question, you can multiply (Quaternion.multLocal) the vert quaternion by the hor quaternion to combine both rotations.

3

With multLocal only the horizontal works.  Nothing happens with the vertical.  However I think this may be involved with problem 1.  This is all of my code:


Quaternion vert = _cameraNode.getLocalRotation().fromAngleAxis( -FastMath.PI/_tank.getTurretElevation() , new Vector3f(1,0,0));
       
Quaternion hor = _cameraNode.getLocalRotation().fromAngleAxis( FastMath.PI/_tank.getTurretHorizontal() , new Vector3f(0,1,0));
       
Quaternion both = vert.multLocal( hor );
       
_cameraNode.setLocalRotation( both );



Vert works alone when that 1 line of code is all I have, but after I add the line where I assign hor.  Vert does nothing and only hor works.
4

You are not doing it correctly, getLocalRotation().fromAngleAxis() does not create a new quaternion so you are modifying the same quaternion as vert, which simply overwrites the vertical rotation. You need to multiply the rotation by a new quaternion.