Hi list, I have a question that could be more related to a jts-user list but hopefully someone can help me.
I have two set of Geometry objects (a set of Points and a set of Multipolygons) and I have to check which of them intersect to get the mapping of Polygon->Points. geometryObjectA.intersect(geometryObjectB) returns true or false and the simplest but quite inefficient solution is: two nested loops iterating over both sets and check each pair if it intersects. Since a point could be intersected by more than polygon (if it lies on a edge or even a vertex) no breaks could be used in the loops. Very inefficient, or? I'm neither an expert in algorithm optimization nor in jts and geotools libs therefore I'd like to know: Are there convenience functions in one of them that offer optimized algorithms for interection/union/.. tasks of geometry sets? If not: What should I do instead of iterating two times over these sets? The Multipolygons are quite complex (>1000 or even >10000 vertices and consisting of several polygons). I was thinking of first intersecting the Points with the envelope of the Multipolygons and only if this matches checking the Multipolygon itself. Other optimization ideas? Barking up the wrong tree? I was also thinking of storing the MultiPolygons in a (spatial) database, create an index and le the database do the intersection and hope that they have optimized it :-) Thanks for any help! Jürgen -- GRATIS für alle GMX-Mitglieder: Die maxdome Movie-FLAT! Jetzt freischalten unter http://portal.gmx.net/de/go/maxdome01 ------------------------------------------------------------------------------ _______________________________________________ Geotools-gt2-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users
