[GRASS5] Polygon Simplification... (d.area revisited)

Glynn Clements glynn.clements at virgin.net
Tue Dec 11 10:48:18 EST 2001


Alex Shevlakov wrote:

> I guess this is to enable functions like R_polygon_abs
> to handle islands?

R_polygon_abs wouldn't be the right place for it. However, it would
allow d.area to tesellate the shape into a set of convex polygons,
each of which would be passed to R_polygon_abs.

The input to R_polygon_abs is just a list of points, which implies a
single continuous path. Complex shapes (with islands) comprise
multiple paths, requiring either a list of lists of points, or
distinct moveto/lineto operations (as in PostScript).

Also, doesn't v.report need something like this for area computations?

-- 
Glynn Clements <glynn.clements at virgin.net>



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