Hi All, I think shapely is astonishingly cool, and I'm using it for preprocessing groundwater model input. I had somehow overlooked the shapely.ops.polygonize function, and I seriously need to be able to manufacture polygons from collections of shapes. What I want to do is have the user digitize line-strings that, when interescted, map out polygons. However, I don't want them to have to exactly digitize the nodes where they line-strings intersect. When I tried polygonize(), it only works if my line-string end points connect. I need something that's more like a "clean-and-build" operation. Also, in addition to the polygons (they map out domains of varying aquifer properties), I need the modified line-strings that bound the polygons, as I impose analytic functions along the line segments, and a way to identify the "left" and "right" polygons for each modified line-string. I'll throw away the dangling ones...
Anyhow. has anyone implemented this in a more generic way? If it exists, that would be great. If not, should I just use LineString.intersect() to find intersections, split strings, and then send the resulting strings to polygonize? Then I can scan the modified line-strings, looking for "left" and "right" by moving a bit to the side of a segment and asking which polygon the point is in. If a line-string has the same polygon on both sides, they're dangles and I throw them away. Has anyone done this already? If not, will my strategy work? If I need to implement it, I will, and I'll gladly release it under LGPL. THANKS! --vic -- Vic Kelson [email protected]
_______________________________________________ Community mailing list [email protected] http://lists.gispython.org/mailman/listinfo/community
