PolyPolygon and PolyPolyline in GDI+   

I have a graphics app that uses GDI.   I would like to add support for color 
transparency.   All our GDI calls are in one place.  I would like to make a 
helper class that mimics all the drawing primitives:  Polygon, PolyPolygon, 
Rectangle, PolyLine, PolyPolyline, MoveTo, LineTo, etc.   Then I could update 
all our existing GDI calls to use the helper.   The helper class would 
determine if the primitive is using a transparent color or not and if so, use 
GDI+, otherwise, continue using GDI.

The problem is that there's not a one to one correspondence between GDI 
primitives and GDI+ primitives.  For example, GDI+ does not support 
PolyPolygon and PolyPolyline.   

1) Has anyone already created a helper class that maps GDI drawing calls to 
GDI+?
2) Where can I find a robust implementation of PolyPolyline and PolyPolygon 
for GDI+?

John

date: Thu, 27 Mar 2008 07:10:00 -0700   author:   John Lutz