RigidBody Rotation

Medo Mex · 2012-11-30T06:16:26

Lets say that I have a tank and want this tank to rotate and look at another area, how do I complete the following code to make the tank rotate 'slightly' every time this method is called? void RotateLeft(float timeElapsed) { btCollisionObject* obj = dynamicsWorld->getCollisionObjectArray()[0]; btRigidBody* body = btRigidBody::upcast(obj); if (body && body->getMotionState()) { btTransform worldTrans; worldTrans = body->getCenterOfMassTransform(); // ***** Need the rest of the code to rotate the tank ***** } }

Math and Physics Programming

Started by Medo Mex November 29, 2012 11:40 AM

11 comments, last by Medo Mex 11 years, 5 months ago

BCullis

1,955

November 29, 2012 10:11 PM

A little digging in the bullet docs revealed:
btMatrix3x3::setEulerYPR ( const btScalar & yaw,
const btScalar & pitch,
const btScalar & roll
)

So I'm assuming you could use that to create a btMatrix3x3, and then apply that to a btTransform's origin that can be applied to the btRigidBody.

If someone could update the two commented lines with the appropriate code, it will be exactly what I want.
[/quote]

No one is here to just write your code for you. You're explicitly asking people to do that. Try and have a little courtesy, it's a forum for information sharing, not task orders.

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alh420

5,995

November 29, 2012 10:29 PM

You got pretty much exactly what you wanted in the first post.
Here its modified with setting yaw, pitch and roll:

btMatrix3x3 orn = m_pRigidBody->getWorldTransform().getBasis(); //get basis of world transformation
btMatrix ypr;
ypr.setEulerYPR(0.2f,0.1f,0.1f);
orn *= ypr //Multiply it by rotation matrix, yaw, pitch, roll
m_pRigidBody->getWorldTransform().setBasis(orn); //set new rotation for the object

Edit: