[android-developers] Re: How do you display many points on a map?
Right. And thanks. Incorporating these suggestions has definitely moved things along. Only draw what can be seen on the screen (pay attention to the map bounds) and only up to a usable number of points. Seems obvious, but when you're learning the low level stuff, it's easy to lose sight of high-level design principals. Adhering to those principals, I figured out I can define my own Overlay that can draw a sufficient number of points. The clustering idea sounds interesting, but well beyond me, at least for the time being. I didn't realize there was a separate Maps API group. Now I know. I'm investigating if you can control when Overlays are asked to draw, so I'll head over there for my questions about that... On Jun 30, 12:30 am, "Maps.Huge.Info (Maps API Guru)" wrote: > The standard way of handling the "toomanypoints" problem is to use a > clustering system, either server based or client based. Clustering > converts themanymarkers that can appear in one area, usually > determined by a matrix, into a single marker. > > Another method is to limit what is loaded into the map by using the > map bounds as a selection criteria. As the map moves, newpointsare > loaded and ones out of view are dropped. > > Still another method is to use an image overlay instead of > individualpointsand develop your own method to make thepointsactive. There > are several strategies to accomplish this but essentially, the meta > data associated with the image is loaded into an array that is > analyzed as the pointer moves. This method works better than > individual markers as there are far fewer objects and DOM nodes > created. > > If you're interested in learning more about these methods, I suggest > visiting the Google Maps API discussion group and research the > archives. There's a lot of information on these specifics on that > forum. > > -John Coryat --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~--~~~~--~~--~--~---
[android-developers] Re: How do you display many points on a map?
The standard way of handling the "too many points" problem is to use a clustering system, either server based or client based. Clustering converts the many markers that can appear in one area, usually determined by a matrix, into a single marker. Another method is to limit what is loaded into the map by using the map bounds as a selection criteria. As the map moves, new points are loaded and ones out of view are dropped. Still another method is to use an image overlay instead of individual points and develop your own method to make the points active. There are several strategies to accomplish this but essentially, the meta data associated with the image is loaded into an array that is analyzed as the pointer moves. This method works better than individual markers as there are far fewer objects and DOM nodes created. If you're interested in learning more about these methods, I suggest visiting the Google Maps API discussion group and research the archives. There's a lot of information on these specifics on that forum. -John Coryat --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~--~~~~--~~--~--~---
[android-developers] Re: How do you display many points on a map?
2009/6/29 guinyard > > I understand the notion of overlays and all, but what if I want to > display thousands of points on a map? The map becomes unresponsive > after a few hundred OverlayItems are added. What's the best approach > for doing this? If they are passive points, that don't accept user input you should be able to draw an image. If they are active points that do accept user input then you need to work out what is seen on screen and what isn't and limit the number of points shown in general --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~--~~~~--~~--~--~---
