i do some research on how coordinate systems are handled in openGL.
here is a example how [rotateXYZ] works.
it does the same, by using a marix stack, but not in GL but outside, in pd - per pedes 
i guess one could say this is reinventig a wheel, but it actually has a purpose.
if you rotate a coordinate system with [rotateXYZ] you loose the world coordinates of the objects in the co.sys. - this is bad if you want to select that object.
this patch outputs world coordinates.
and i think its a useful example that helps to understand how the stuff works on base level.
if some people are interested in this, ill include some examples on this things in gem_engine.
id also recommand you to use this patch with it, though its not necessary.
download here...www.3rd-eye.at