Question about Confuted and Silvercord's 3D rotation tutorial.

Hi all.

I've been reading through the Rotation Tutorials on this site at Part Three: Rotation About an Arbitrary Axis, and there's one point I'm not clear on.

It says I should

Quote:

-Calculate the Perpendicular component, multiply it by the cosine of the angle you are trying to rotate through

-Calculate the cross product between the vector you are trying to rotate about and the vector you are rotating, multiply it by the sine of the angle

-Add the results together

-Add the component of the vector you are trying to rotate that is parallel to the vector you are rotating about

and then supplies a very handy rotation matrix.

My question: Does multiplying my orientation vector by this matrix apply the above steps? Or should I do the steps and then apply the matrix to the result?

If I do have to do these steps first, could someone please elaborate on the last one - "Add the component of the vector you are...." - I don't get it.

Thanks for any help.