In C OpenGL, you can do something like this to use matrices for computation without affecting context: glMatrixMode (GL_MODELVIEW) ; glPushMatrix () ; glLoadMatrix (your_matrix) ; // do whatever you want with your your matrix // for exampl glMultMatrix (your_matrix2) ; ... // at the end of your calculations use glGetFloatv (GL_MODELVIEW_MATRIX, your_matrix_result) ; glPopMatrix () ; // nothing has changed !!! I'm not exactly sure how this is done with HOpenGL. i.e., how can I get the result of a matrix transformation not effecting the MODELVIEW, etc. matrices? Could someone give an example? Thanks, Jamin -- View this message in context: http://www.nabble.com/%28not-%29-using-preservingMatrix-tf2926697.html#a8181... Sent from the Haskell - HOpenGL mailing list archive at Nabble.com.