Re: [mapserver-users] Help in plotting several tens of thousand 'pies'
Pies = Pie Chart? MapServer can do server-side pie charting -- http://mapserver.org/output/dynamic_charting.html, might that help? -Original Message- From: mapserver-users-boun...@lists.osgeo.org [mailto:mapserver-users-boun...@lists.osgeo.org] On Behalf Of Eichner, Andreas - SID Sent: Tuesday, January 20, 2015 1:31 AM To: 'Arun Cherian'; mapserver-users@lists.osgeo.org Subject: Re: [mapserver-users] Help in plotting several tens of thousand 'pies' We used to serve this data as a vector for smaller systems via GeoJSON and use Openlayers 2 to render on a slippery map. For a few hundred sites it was fine, no performance degradation or issues. When we started testing with larger real life samples, the browser would literally crawl. I understand it is because each vector feature adds to the DOM and there is a limit Do you need to display all at once? I've read that OpenLayers can use different strategies to fetch data. Retrieving everything when the layer is created is of course the simplest one. A more sophisticated solution would be to use a BBOX filter and load data on demand. But this only makes sense if not every feature is required at the same time. ___ mapserver-users mailing list mapserver-users@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/mapserver-users ___ mapserver-users mailing list mapserver-users@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/mapserver-users
Re: [mapserver-users] Help in plotting several tens of thousand 'pies'
We used to serve this data as a vector for smaller systems via GeoJSON and use Openlayers 2 to render on a slippery map. For a few hundred sites it was fine, no performance degradation or issues. When we started testing with larger real life samples, the browser would literally crawl. I understand it is because each vector feature adds to the DOM and there is a limit Do you need to display all at once? I've read that OpenLayers can use different strategies to fetch data. Retrieving everything when the layer is created is of course the simplest one. A more sophisticated solution would be to use a BBOX filter and load data on demand. But this only makes sense if not every feature is required at the same time. ___ mapserver-users mailing list mapserver-users@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/mapserver-users
[mapserver-users] Help in plotting several tens of thousand 'pies'
Hello, I was hoping the experience of the members here would help in something I was researching. A bit of background. We have cellular data for wireless operators in a DB. The data is referred to as a 'System' and consists of around 50k 'sites' and each site has 3 or more 'cells' on it. It would in a map perspective look like a small circle with several pies around it. So all in all looking at a few hundred thousand polygons to plot. We used to serve this data as a vector for smaller systems via GeoJSON and use Openlayers 2 to render on a slippery map. For a few hundred sites it was fine, no performance degradation or issues. When we started testing with larger real life samples, the browser would literally crawl. I understand it is because each vector feature adds to the DOM and there is a limit. We have used mapserver to provide an OSM map for our base layer, and I was thinking of serving the system vector data as raster/tiles. A few questions I have are below.Apologies for the long post. Any comment appreciated. 1. Is there a way to easily draw a pie? We store center, azimuth and other 'metadata' for the pie in the DB and create a polygon on the fly in Openlayers, is there a faster way to do it in mapserver when creating the raster? 2. Vector features can be 'clicked' or selected, can the same be done for raster layers, so we know which site/cell is selected? Based on the site clicked, we fetch data from another DB table to open a popup. 3. Client side users have the option to apply their own coloring scheme to the pies, how would that be done at the server side, sending a request for re-rendering the pies? Would this create a scenario where several users hit the server with a lot of re-render requests? Is this the right way to go about it? A lot of the neat features of vectors are because all the data is readily available on the client side, but that is also the reason for the performance hit when we load a few thousand sites via GeoJSON. Thanks, Arun ___ mapserver-users mailing list mapserver-users@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/mapserver-users
