I am trying to find the orientation of a framemarker around its z-axis.
The camera will be pointed head-on at the framemarker. I believe this means that the z-axis of the framemarker has the same direction as the camera axis.
I understand I can get the 3x4 pose matrix of a trackable and build a new 3x3 rotation matrix from it.
Are there utility functions to go straight from the 3x3 rotation matrix to rotation angles around x, y and z axes? Or do I need to program these myself?
Any help greatly appreciated. A code sample would be great.