I am studying bullet.I've written a program based on OpenGL which can move the character with the mouse click on the screen like Warcraft.I want to know that i got the angle that the character needs to rotate, how can i apply the rotation in the bullet world?
The demo is
btMatrix3x3 orn = m_ghostObject->getWorldTransform().getBasis();
orn *= btMatrix3x3(btQuaternion(btVector3(0,1,0),-0.01));
m_ghostObject->getWorldTransform ().setBasis(orn);

and how to calculate the quaternion?
who can help me!!