Can anyone help me with an Splus v6.0(2) (Windows) problem: I simply want to
map shaded polygons that overlap. At the moment I'm using different colours
for each polygon, but you can't see the portions of the polygon that were
printed previously. Is there some way to set the polygon colour to
translucent?
Below are some comment from another user, who suggested writing code prog to
find overlapping portions of polygons and then to plot each portion
separately.
Thanks,
Peter Ward
Dept. of Biology
Dalhousie University ph. (902) 494 3910
Halifax B3H 4J1 fax (902) 494 3736
CANADA e-mail: ward@mathstat.dal.ca
Off the top of my head I don't know an easy way.
I know there are some routines around to tell whether a point is in or
out of a polygon. I can send you one I use if you want. Then maybe you
can adjust the color based on how many polygons are covering the area.
In effect you'd have to create new polygons that define the overlapping
areas and then give them a different color or a different numerical
value for the image function to color.
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