>> Do you have a short draft how you want to detect that two areas are >> touching? > When two nodes follwing each other from one polygon are inside the other. Or > on the outline of it. > > Yeah, and you will have to test some 100 thousands of nodes, if they lie inside one of a 10 thousands polygons. This will be as a number of thumb 10 ^ 9 tests (or add some more zeroes) of tests if the is node in polygon area, which is not a cheap test by itself.
You will need at least some tricks with quadtrees or bounding box checks to achieve reasonable runtimes. In general I really like the idea of merging polygon areas. I have mentioned it already in this mailing list. But up to now I haven't found any practicable solution. The algorithm should merge two polygons even if there is some space between it. Think of a map of small woods or lakes, which should be combined to a bigger one and simplified, while zooming out of the map. They are *not* overlapping or touching in most of the cases. I don't want discourage you, if you think, you have some working solution, please let us know. Regards, Johann _______________________________________________ mkgmap-dev mailing list [email protected] http://www.mkgmap.org.uk/mailman/listinfo/mkgmap-dev
