Well, my client requests that my application be able to turn off the clustering feature (not the OpenLayers clustering, but the logical concept of it, anyway), and to turn it back on again. Consider a very dense GPS tracking system for someone in a car or on foot. If you log the coordinates every second, it starts adding up fast and in about an hour you're pushing 4000 points. Clustering helps the rendering so the application can retain some performance by drawing 50 points rather than 4000 points. Secondly, its hard to see any kind of trend or path that the target took with clustering on because the real points are obfuscated by bigger points that represent more than one of those points.<br>
<br>So this is what I ended up doing. To "turn off" clustering, I just have my application edit the threshold of the cluster to something insane like 1000, then perform map.zoomIn(); then map.zoomOut(). I do this in succession because, as you say, zooming in will redraw the clustering. And since the user didn't request a zoom, we zoom back out.<br>
<br><div class="gmail_quote">On Wed, Oct 7, 2009 at 3:38 AM, Christopher Schmidt <span dir="ltr"><<a href="mailto:crschmidt@metacarta.com">crschmidt@metacarta.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div class="im">On Tue, Oct 06, 2009 at 04:27:21PM -0800, Jonathan Sawyer wrote:<br>
> Christopher et al,<br>
><br>
> Clustering works for me :) However, is there a way to turn off clustering<br>
> dynamically? I.e., call a function to deactivate it, zoom in or out without<br>
> clustering, then turn it back on, all without having to drop and reload<br>
> layers?<br>
<br>
</div>Not really. SOme people have done it though, I believe. Though I'm not sure<br>
why you'd want to deactivate-zoom-reactivate? That doesn't make sense to me,<br>
since on zoom, the clusters will recalculate...<br>
<br>
-- Chris<br>
<div><div></div><div class="h5"><br>
> Thanks again in advance!<br>
><br>
> Jon<br>
><br>
> On Mon, Oct 5, 2009 at 10:27 PM, Christopher Schmidt <<br>
> <a href="mailto:crschmidt@metacarta.com">crschmidt@metacarta.com</a>> wrote:<br>
><br>
> > On Mon, Oct 05, 2009 at 04:07:27PM -0800, Jonathan Sawyer wrote:<br>
> > > Hi everyone,<br>
> > ><br>
> > > I have a feature class of points that displays a breadcrumb trail of GPS<br>
> > > points for a target. When zoomed out to the full extent of the map,<br>
> > > OpenLayers renders 1000+ points in a tiny little area, thus reducing<br>
> > > performance of my application. Is there a way I can tell OpenLayers to<br>
> > > render just one point for a bunch of points within a given radius of the<br>
> > > point? For example, when zoomed out to the full extent, I would rather<br>
> > have<br>
> > > 1 to 3 points rendered rather than 1000+, but then be able to see every<br>
> > > point applicable when zoomed in.<br>
> ><br>
> > Clustering.<br>
> ><br>
> > <a href="http://openlayers.org/dev/examples/strategy-cluster.html" target="_blank">http://openlayers.org/dev/examples/strategy-cluster.html</a><br>
> ><br>
> > > Thanks in advance for any help.<br>
> > ><br>
> > > Jon<br>
> ><br>
> > > _______________________________________________<br>
> > > Users mailing list<br>
> > > <a href="mailto:Users@openlayers.org">Users@openlayers.org</a><br>
> > > <a href="http://openlayers.org/mailman/listinfo/users" target="_blank">http://openlayers.org/mailman/listinfo/users</a><br>
> ><br>
> ><br>
><br>
><br>
> --<br>
> Jonathan Sawyer<br>
> Geographic Information Network of Alaska (GINA)<br>
> University of Alaska Fairbanks<br>
<br>
</div></div><font color="#888888">--<br>
Christopher Schmidt<br>
MetaCarta<br>
</font></blockquote></div><br><br clear="all"><br>-- <br>Jonathan Sawyer<br>Geographic Information Network of Alaska (GINA)<br>University of Alaska Fairbanks<br>