I'm trying to get a better grip in the gl commands to send to jit.gl.sketch. So: In the Jitter tutorials, we're told how to rotate an sketched shape, and to do so we need to use 'glmatrixmode modelview, glpushmatrix, ..., gl popmatrix'. However, the glrotate command seems to work without these. Why do we need the push and popmatrix commands? Like I said, just trying to understand! I can't quite get the explanation the tutorials give. Thanks for your help.