# OpenGL How can I get the roatation in PhysX in opengl

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Can someone tell me how to get the rotation from PxRigidDynamic class in PhysX I'm using PhysX-3.2.4. I tried to look the docs in nvidia and also tried to used m_helicopter->getGlobalPose().q.getAngle() and m_helicopter->getGlobalPose().q.x which the m_helicopter is a PxRigidDynamic but they both returning not radius or degree , thanks

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getGlobalPose returns a PxTransform, and it's q member is a PxQuat(ernion).

You can directly convert a PxTransform to a 4x4 matrix with:

PxMat44 tempMat = PxMat44(xform);

Or you can convert the quaternion to an axis-and-angle rotation with:
float angle;
PxVec3 axis;

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Just curious how can I get the rotation from the first method ? becasue on the internet seems mixed up a lot of stuff which is not openGL , it will be great it you can point me to the right direction , thanks

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What are you trying to do, exactly.

The first method gives you a 4x4 transformation matrix, which contains the rotation and translation. You can use this directly as your object's "world" matrix in GL/D3D.

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Im making the heading indicator which need the rotation from the helicopter ,and also the second method you told me it seems the maximum is only 6.18 not 6.28 for some reason that i dont understand

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[X.x  Y.x    Z.x    Tx]

[X.y Y.y    Z.y     Ty]

[X.z  Y.z    Z.z     Tz]

[0     0       0       1]

You can get the helicopters right, up and forward vectors from the matrix itself. Those are 3 vectors in world coordinates. Whatever you are doing with heading would deal with the Zx, Zy, Zz vector.

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