Members
    Line loop primitive where each vertex (or index) after the first connects a line to
the previous vertex, and the last vertex implicitly connects to the first.
    Line strip primitive where each vertex (or index) after the first connects a line to the previous vertex.
    Lines primitive where each two vertices (or indices) is a line segment.  Line segments are not necessarily connected.
    Points primitive where each vertex (or index) is a separate point.
    Triangle fan primitive where each vertex (or index) after the first two connect to
the previous vertex and the first vertex forming a triangle.  For example, this can be used
to model a cone or circle.
    Triangle strip primitive where each vertex (or index) after the first two connect to
the previous two vertices forming a triangle.  For example, this can be used to model a wall.
    Triangles primitive where each three vertices (or indices) is a triangle.  Triangles do not necessarily share edges.
