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Google Maps Points do not appear until low zoom levels

I'm working on a (Perl) program that uses the Google Maps API and a KML file to pull data from a database that creates points on the map. I have that much done, but the points only appear after I zoom pretty much all the way in, to a zoom level where only one point is showing.

The default zoom only shows my small city (3-5 miles) so I thought all the points would be able to show. Does anybody know how to get all of the points to show up at city-wide level as开发者_JS百科 opposed to only showing up when zoomed all the way in?

Any help is greatly appreciated. Thanks!

Edit: Added a JavaScript tag because I've seen a lot of work done with Google Maps using JS, and considering the problem really isn't language-specific, I figured some of those developers might be able to offer some insight.


Try to incorporate the <Lod> tag in your KML, which is child of a <Region>. You can define this once per placemark you get from your DB. or only once per query (defined by minLat, maxLat, minLong, maxLong). In the first case the LodPixels is a constant whereas in the latter case you must calculate it as a function of the region size. It sure works in Google Earth and may work as well in Maps. Look here to see it work in Earth API (JS)

....
<Region>
    <LatLonAltBox>
        <north>###</north>
        <south>###</south>
        <east>###</east>
        <west>###</west>
        <minAltitude>###</minAltitude>
        <maxAltitude>###</maxAltitude>
    </LatLonAltBox>
    <Lod>
        <minLodPixels>###</minLodPixels>
        <maxLodPixels>###</maxLodPixels>
        <minFadeExtent>###</minFadeExtent>
        <maxFadeExtent>###</maxFadeExtent>
    </Lod>
</Region>
....
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