Section: OpenGL Models
glnode command
is 
glnode(name,material,pointset)
where material is the name of a material that has already been
defined with gldefmaterial, pointset is a 3 x N matrix
of points that define the geometry of the object.  Note that the points
are assumed to be connected in triangular facts, with the points
defined counter clock-wise as seen from the outside of the facet.
FreeMat will compute the normals.  The name argument must
be unique.  If you want multiple instances of a given glnode
in your GLWindow, that is fine, as instances of a glnode are
created through a glassembly.