GLNODE GLNODE Create a GL Node

Usage

Define a GL Node.  A GL Node is an object that can be displayed
in a GL Window.  It is defined by a triangular mesh of vertices.
It must also have a material that defines its appearance (i.e.
color, shininess, etc.).  The syntax for the 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.  
