Geographic Help and advice Methods Stack Exchange
I’ve to develop a webapp that’ll have got to show a large number of polygons over a webpage, with complex filtering methods. The source info not ever variations (I’ll purely reload a fresh version for the DB virtually every couple months).
I will very likely use OpenLayers for the client-side. I developed a prototype that drawed the characteristic as vectors in javascript, but I might love to switch to server-side rendering for significantly better operation. I could very likely do my app connecting immediately OpenLayers to your very few many different WMS levels in GeoServer (postgis backend) with CQL filters, enjoyreplicachristianlouboutin.com but I have the feeling GeoServer isn’t really tremendously adaptable when applying a combination of elaborate filters and dynamic styling of my WMS
Through the developer standpoint, a more confortable/flexible procedure seems to use GeoDjango and its spatially-enabled data types to make a dynamic (subject material and styling) KML file of my details. A (quite possibly naive) beautiful alternative is going to be to integrate WMS rendering (and maybe caching) layer relating to the OpenLayers consumer
1) Openlayers sends user question to “intermediate layer”
two) This levels ahead question to your GeoDjango application, christian louboutin replica receive a KML file and render it as WMS and return it to OpenLayers.
(alternatively, OL could also talk precisely to GeoDjango it sould make use of a middleware to postprocess its KML result just before returning it).
As my data almost never ever improvements, http://www.replicanewchristianlouboutin.com I could then profit from a caching device this kind of as GeoWebCache involving OL
I understand Google Maps API do server-side rendering of KML files when they’re colossal, but it can be a black box tied for their JS library, and I might in reality love to do a thing very similar with OL.
I have completed several queries, but was not able to find any device with the “intermediate layer”. WMS servers these kinds of as GeoServer/Mapserver can utilize a KML data source, but it really looks constrained into a static file somewhere with the filesystem, instead of from the dynamic URL.
Does a tool similar to this exists ? Or is my technique easily incorrect ? Thanks in advance,
Very first I preferably should explain to that i’m not seasoned with KML and GeoDjango (mainly I do not know very well what are classified as the abilities of GeoDjango) in spite of this I might propose you to check out SLD specification and exactly how it is really utilised with Openlayers + Geoserver stack (I presently did few implementations for dynamic styling based upon the attribute values and rendered maps by means of Geoserver WMS and SLD).
Regarding your workflow : it appears alright but I couldn’t perceive the piece “get a KML file and render it as WMS” considering the fact that generally WMS is usually a program that results in visuals dynamically based on your vector or raster info. In vector data circumstance it really is possible to delegate rendering to WMS with some precise variations that may be according to rules in accordance to info set.
I see. Probably there is usually greater options nevertheless it looks such as you can do all the manipulations in GeoDjango on server side then you can easlily feed the GeoServer using your dataset. Then you really can use default types or by way of SLD it is possible to make styled map requests to WMS. For filters you are able to use the identical tactic : It is possible to use OGC filtering abilities and when they are not adequate can make use of your server side remedies That is much more or a lot less can be done using the “Openlayers – GeoWebCache – GeoServer – PostGIS” stack as capdragon outlined. yteslax Jun thirty ’11 at thirteen:22
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