oops, already found something missing: the constants for the magic numbers in the GLatLng GFLineSegment.GetIntersection(GFLineSegment) function in the GLatLng constructors (the stuff in capital letters that begins with MN_). just set them as you please, any number outside the phi/lambda-degrees-interval will do; i usually use 1001, 1002 and so on.
On Jul 15, 1:26 pm, Götz Freytag <[email protected]> wrote: > the method proposed by Andrew Leach only works, if the outer polygon > is concave, though. what you should do iot test whether *any* regular > polygon lies entirely within another, is to check for each edge of > polygon p if there is an intersection with any of the edges of polygon > q. if you find at least one (two, actually) intersection(s), then the > polygons obviously have got an intersection-area. if there is no > intersection, then polygon p lies either entirely within or outside of > polygon q. in this case you would have to use Mike William's > GPolygon.Contains(GLatLng) method like polygon_p.Contains > (polygon_q.getVertex(0)); if this returns true and there are no > intersections of edges, then polygon p contains polygon q. > > On Jul 14, 3:29 pm, Andrew Leach <[email protected]> > wrote: > > > On Jul 14, 12:13 pm, Prabu Proxy <[email protected]> wrote: > > > > Suppose I have 2 Gpolygons. They may overlap with each other or one > > > inside of another, but are not identical. How could i find out whether > > > the 2 Gpolygons are intersects or inside to one another? > > > Use Mike's EPoly extension:http://econym.org.uk/gmap/epoly.htm > > > Loop through all the vertices of one polygon; for each vertex, test > > whether the other polygon contains it. If it does, increment a > > "contains" variable. If it doesn't, increment a "not-contains" > > variable. [The names of those variables are up to you] > > > At the end of the loop, if your "contains" variable is the same as the > > number of points checked, the polygon is entirely contained within the > > other. If the "not-contains" variable is the same, the polygon is > > entirely outside the other. > > > Note that with this method, if you have two concentric polygons and > > test whether the outer one is contained by the inner one, the result > > will be that it isn't. You shouldn't assume that there is no > > intersection until you have tested the other way round as well. > > > Andrew --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Google Maps API" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/Google-Maps-API?hl=en -~----------~----~----~----~------~----~------~--~---
