TITLE: Measuring rotation and translation differences between two matrices
QUESTION [5 upvotes]: I am developing a docking application in which I want to have for every step the difference between the target transformation matrix and the user's transformation matrix. Now I don't have any problem with the coding part but rather with the linear algebra part.
So let's say T is my target transformation matrix, and U is the user's transformation matrix.
To get the difference between the two matrices I do:
(U^-1) * (T) = Difference

Now my matrices are formed with translation, rotation and scaling.
My question would be how I should measure the total translation difference as well as the total rotation difference (not interested in the scaling part).
Thanks in advance,

REPLY [3 votes]: This is known as a Procrustes problem or one of it's generalizations, depending on how advanced you want to make it.