I agree, don't see any evidence of using KML at different zoom levels - for the main layers.
The only evidence of KML I can see from the source code, is for displaying pocket queries. I'm not a premium member, so don't have access to PQs to see how they work. It appears, to just load one page at a time. So little danger of reaching the file size limits. On Thu, Jul 28, 2011 at 1:28 AM, Michael Geary <m...@mg.to> wrote: > Where do you see them using a KML layer? I don't see any evidence of that. I > watched the traffic at several zoom levels, both less than and greater than > 11, and I see the same map.tile image downloads at every zoom level. > That would also be a very odd way to program this map: Why support two > completely different methods of displaying markers instead of one? > I do see that they avoid making the map.info JSON calls when you roll over a > marker at small zoom levels, which makes sense. > -Mike > > On Wed, Jul 27, 2011 at 3:03 PM, amnesia7 <col.gib...@gmail.com> wrote: >> >> Great, thanks a lot. >> >> So it sounds like they use kml/kmz to overlay the icons/markers onto >> the map using the kmlLayer by Google at low zoom levels (1-11). >> >> I think when you get down to zoom levels 12-20 they start using tile >> overlays that create transparent map tiles with just the icons/markers >> on to position icons on the map over the normal google maps. When you >> mouseover a map marker on the map at these zoom levels it grabs the >> info/json file about the icons for the particular map tile being >> hovered over. >> >> At lower zoom levels it doesn't offer any info about the individual >> icons, only zoom seems to be available. >> >> I still wonder about the full world view. If they are using a kml/kmz >> approach; how many points can be contained within the 10Mb/3Mb limit >> set by google? Has anyone any idea, I'm curious? Does the kmlLayer- >> google-thing offer a listener for when an icon/marker is clicked so >> that the info window can be done using ajax rather than the info >> needing to be part of the kml file to allow for more points with >> minimal data about each? >> >> Apart from the nicer icons/markers that they've used at the higher >> zoom levels is there another reason to justify the extra effort >> required in their approach with map tiles for higher zoom levels? >> >> Col >> >> >> On Jul 26, 5:50 pm, Michael Geary <m...@mg.to> wrote: >> > You can see what they are doing by opening the Network tab in your >> > browser's >> > debugger (e.g. Firefox or the native debugger in Chrome or Safari). Move >> > the >> > map around and you'll see a number of image GET requests like this one: >> > >> > http://www.geocaching.com/map/beta/map.tile?x=2625&y=5716&z=14 >> > >> > As you can see, they have generated (or generate on the fly) their own >> > map >> > tiles containing the marker images. >> > >> > When you move the mouse over one of the markers, they issue a GET >> > request >> > for some JSON data: >> > >> > http://www.geocaching.com/map/beta/map.info?x=2635&y=5725&z=14 >> > >> > There must also be one other bit of code/data that lets them know when >> > the >> > mouse is actually over a marker or not (because they don't issue those >> > map.info requests until the mouse is actually over a marker). I didn't >> > investigate that bit, but you could track it down with the same methods. >> > >> > -Mike >> > >> > >> > >> > On Tue, Jul 26, 2011 at 9:21 AM, amnesia7 <col.gib...@gmail.com> wrote: >> > > Can anyone explain how the new beta geocaching site might have managed >> > > to get all those markers displayed? >> > >> > >http://www.geocaching.com/map/beta/ >> > >> > > I assume they're using a kml file merged into maps by Google some how >> > > but isn't there a 3Mb limit on the zipped kml or 10Mb limit on the >> > > unzipped version? Wouldn't the number of geocaches all over the world >> > > blow that limit when they zoom out to show full map? >> > >> > > Would they be limiting the number of entries that are actually >> > > displayed when zoomed out somehow (server-side?) since when zoomed out >> > > there could actually be quite a few entries within the same area of >> > > the map covered by the icon itself? >> > >> > > There are probably other maps that have the same issue of displaying >> > > millions of entries that goes beyond the kml filesize limit but this >> > > was the example I found and was wondering how they could do that since >> > > I have a lot of markers to display and was interested to know how this >> > > had been achieved. >> > >> > > Thanks >> > >> > > -- >> > > You received this message because you are subscribed to the Google >> > > Groups >> > > "Google Maps JavaScript API v3" group. >> > > To post to this group, send email to >> > > google-maps-js-api-v3@googlegroups.com. >> > > To unsubscribe from this group, send email to >> > > google-maps-js-api-v3+unsubscr...@googlegroups.com. >> > > For more options, visit this group at >> > >http://groups.google.com/group/google-maps-js-api-v3?hl=en. >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Google Maps JavaScript API v3" group. >> To post to this group, send email to >> google-maps-js-api-v3@googlegroups.com. >> To unsubscribe from this group, send email to >> google-maps-js-api-v3+unsubscr...@googlegroups.com. >> For more options, visit this group at >> http://groups.google.com/group/google-maps-js-api-v3?hl=en. >> > > -- > You received this message because you are subscribed to the Google Groups > "Google Maps JavaScript API v3" group. > To post to this group, send email to google-maps-js-api-v3@googlegroups.com. > To unsubscribe from this group, send email to > google-maps-js-api-v3+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/google-maps-js-api-v3?hl=en. > -- You received this message because you are subscribed to the Google Groups "Google Maps JavaScript API v3" group. 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