Thank you for your help. If my polygon table is huge, it would have to consider all the polygon in space? Is there a way I can narrow down only polygons are that in the way between point A and B?
Suhr, Ralf wrote: > > Solving your problem is not realy hard but time expensive. > - install pgRouting > - create one table for the polygons > - create one table for holding linestrings > - write a function that: > - build all possible lines in one polygon (makeline from cross join > points from polygon) > - remove lines wich are outside the polygon > - write lines with extra attribute polygon_id in the linestring table > - run add_vertices (pgRouting function) > - create temporary table for your "two points" (linestring geometry) > - rerun the function for creating linstrings with the two points and all > polygon points > - finaly run shortest_path( join two tables ) > > > -----Ursprüngliche Nachricht----- > Von: [email protected] > [mailto:[email protected]] Im Auftrag von > tommy408 > Gesendet: Donnerstag, 25. Juni 2009 15:35 > An: [email protected] > Betreff: [postgis-users] Shortest path around polygons > > > > I'm really new to PostGIS. I need to solve this problem. Find the > shortest path around polygons from point A to point B. > > Here is a better description: http://alienryderflex.com/shortest_path/ > > How can I do it with PostGIS. Or if you can give me some hints to narrow > my search. > > Thank you. > -- > View this message in context: > http://www.nabble.com/Shortest-path-around-polygons-tp24203378p24203378.html > Sent from the PostGIS - User mailing list archive at Nabble.com. > > _______________________________________________ > postgis-users mailing list [email protected] > http://postgis.refractions.net/mailman/listinfo/postgis-users > _______________________________________________ > postgis-users mailing list > [email protected] > http://postgis.refractions.net/mailman/listinfo/postgis-users > > -- View this message in context: http://www.nabble.com/Shortest-path-around-polygons-tp24203378p24206683.html Sent from the PostGIS - User mailing list archive at Nabble.com. _______________________________________________ postgis-users mailing list [email protected] http://postgis.refractions.net/mailman/listinfo/postgis-users
