Real-Time Physics Simulation Forum

One:I want to use btSliderConstraint->getFrameOffsetA()->getBasis()->setEulerZYX(btScalar _x,btScalar _y,btScalar _z),but I didn't understand the meanings of _x、_y、_z? Also,I dind't know how to use it to set sliding direction?

Two:I want to use btConeTwistConstraint->setMotorTarget(btQuaternion(btScalar _x,btScalar _y,btScalar _z,btScalar _w)),but I didn't understand the meanings of _x、_y、_z,_w? And ,How can I use it?

I was eager to get help,Thanks!