Hi, There are also use cases for density maps weighted by a value of some attribute like sum of dollars lost in traffic accidents. Barnes surfaces does not suit for this, nor unweighted density maps. I have been creating such visualisations with SAGA GIS and Sextante which both have functions for this but the result is a static image that does not suit well for a web map with large scale range. Discussion about this and one nice image in http://gis.stackexchange.com/questions/39074/whats-the-best-way-to-produce-a-density-map-from-weighted-points-in-qgis
It would be nice to be able to do something similar dynamically with Geoserver. -Jukka Rahkonen- ________________________________ Martin Davis wrote: +1 for everything Andrea said about Heatmaps - they are density maps, not interpolation surfaces. Also, the output values are in the range [0,1], which is another reason you saw only one color in your output. On Tue, Jan 8, 2013 at 6:17 AM, Andrea Aime <andrea.a...@geo-solutions.it<mailto:andrea.a...@geo-solutions.it>> wrote: On Tue, Jan 8, 2013 at 3:14 PM, Chris Haste <cha...@airdata.co.uk<mailto:cha...@airdata.co.uk>> wrote: Hi Andrea, I’m not sure I understand. Are you saying that I don’t have a sufficient number of points in my data? I have a regular grid of points covering the entire globe at 1.25 x 1.25 degree intervals. Is this not dense enough? I'm saying a heatmap shows a color based on the different concentration of points, not their value, so if the grid is regular it's normal that you get a solid color. If you want to interpolate a value contained in the attributes of the points instead you have to use the Barnes surface instead. See some docs here: http://suite.opengeo.org/docs/cartography/rt/barnes.html Cheers Andrea From: andrea.a...@gmail.com<mailto:andrea.a...@gmail.com> [mailto:andrea.a...@gmail.com<mailto:andrea.a...@gmail.com>] On Behalf Of Andrea Aime Sent: 08 January 2013 14:09 To: Chris Haste Cc: geoserver-users@lists.sourceforge.net<mailto:geoserver-users@lists.sourceforge.net> Subject: Re: [Geoserver-users] gs:Heatmap problems On Tue, Jan 8, 2013 at 3:03 PM, Chris Haste <cha...@airdata.co.uk<mailto:cha...@airdata.co.uk>> wrote: Hi List, I have been trying to use the new heatmap transformation in version 2.2.3 but I think I must be doing something wrong. I wish to display a layer defined using an SQL view. The query simply returns a Grid of points and for each point there is a temperature value, I am using the round function in the query to round the temperature value to the nearest integer. I am using the SLD below, copied from the example and modified to (hopefully) work with my data. However, the entire map is produced in one colour (#FFFF00) but when I query the map by clicking on it in an Openlayers preview it shows correct values for the Temperatures and different locations on the map yield different values. Any ideas? Heatmaps are about point density, if you want to interpolation function you should look at the Barnes surface transformation instead Cheers Andrea -- == Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information. == Ing. Andrea Aime @geowolf Technical Lead GeoSolutions S.A.S. Via Poggio alle Viti 1187 55054 Massarosa (LU) Italy phone: +39 0584 962313<tel:%2B39%200584%20962313> fax: +39 0584 1660272<tel:%2B39%200584%201660272> mob: +39 339 8844549<tel:%2B39%20%C2%A0339%208844549> http://www.geo-solutions.it http://twitter.com/geosolutions_it ------------------------------------------------------- *** This communication has been sent from World Fuel Services Corporation or its subsidiaries or its affiliates for the intended recipient only and may contain proprietary, confidential or privileged information. If you are not the intended recipient, any review, disclosure, copying, use, or distribution of the information included in this communication and any attachments is strictly prohibited. If you have received this communication in error, please notify us immediately by replying to this communication and delete the communication, including any attachments, from your computer. Electronic communications sent to or from World Fuel Services Corporation or its subsidiaries or its affiliates may be monitored for quality assurance and compliance purposes.*** -- == Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information. == Ing. Andrea Aime @geowolf Technical Lead GeoSolutions S.A.S. Via Poggio alle Viti 1187 55054 Massarosa (LU) Italy phone: +39 0584 962313<tel:%2B39%200584%20962313> fax: +39 0584 1660272<tel:%2B39%200584%201660272> mob: +39 339 8844549<tel:%2B39%20%C2%A0339%208844549> http://www.geo-solutions.it http://twitter.com/geosolutions_it ------------------------------------------------------- ------------------------------------------------------------------------------ Master SQL Server Development, Administration, T-SQL, SSAS, SSIS, SSRS and more. Get SQL Server skills now (including 2012) with LearnDevNow - 200+ hours of step-by-step video tutorials by Microsoft MVPs and experts. SALE $99.99 this month only - learn more at: http://p.sf.net/sfu/learnmore_122512 _______________________________________________ Geoserver-users mailing list Geoserver-users@lists.sourceforge.net<mailto:Geoserver-users@lists.sourceforge.net> https://lists.sourceforge.net/lists/listinfo/geoserver-users -- Martin Davis OpenGeo - http://opengeo.org<http://opengeo.org/> Expert service straight from the developers. ------------------------------------------------------------------------------ Master SQL Server Development, Administration, T-SQL, SSAS, SSIS, SSRS and more. Get SQL Server skills now (including 2012) with LearnDevNow - 200+ hours of step-by-step video tutorials by Microsoft MVPs and experts. SALE $99.99 this month only - learn more at: http://p.sf.net/sfu/learnmore_122512 _______________________________________________ Geoserver-users mailing list Geoserver-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/geoserver-users
