introduction of two new option :

GmshSetOption("General", "Stereo", 1.);
GmshSetOption("General", "Camera", 1.); 

Camera : to use camera instead of rotation matrix 

Stereo : to turn on/off the stereo rendering (for device with left and
right views in the two buffers (left and right) of OpenGL : Works in utils/api_demos/mainGlut