Need to know how to rotate a 3d vector

Hey, I have managed to get rotation and movement sorted out with force call backs now, but one problem remains. I would like to know if there any functions/methods that can be used to change my force vector (forwards force) so that moves the object forwards in the current orientation.

I have had a look at the Quatenion methods and dont really know if it has the methods im looking for. Is there any quick method of multiplying the 3d forward force vector by a 3d/4d matrix which will change the values in the first vector so that the force will always be in the correct direction.

Thanks for any help and replies.

Ryan.

1. if you want, just use the "addLocalForce" to add a force in the local space of the body.

2. to rotate a vector just multiply the quaternion by the vector:

Ogre::Vector3 rotated_vector = rotation_quaternion * vector_to_rotate;

Thanks for the reply, that formula will help a lot now.

Ryan.