filled contours with POLYFILL

[egraves(at)socrates.Berkeley.EDU (Ted Graves)]

Hi all,

I am drawing closed contours over an image, and would like to fill the contours with
a pattern which allows viewing of the image beneath (like a checkerboard).  I have an
array of vertices which i plot using PLOTS, then i tried passing the vertices to
POLYFILL to fill in the enclosed area.  I tried using a pattern of 

[ [255, 0  ]
  [0,   255] ]

to generate a checkerboard, but despite my finger crossing the zeroes in the pattern
are drawn as black and not left undrawn.  Is there any simple way to achieve the kind
of "holey" pattern i'm looking for with POLYFILL?  Or do i need to do something fancy
with POLYFILLV?

Thanks in advance,



Ted Graves
Magnetic Resonance Science Center, UCSF