It might be easier to do this in a custom function in GeoTools rather than in PostGIS - then you could pass in the scale env variable along with the feature that you are drawing.
Ian On Mon, 3 Aug 2020 at 10:15, Richard Duivenvoorde <[email protected]> wrote: > Hi, > > In QGIS there is something what we call 'Geometry-generators': you > actually generate a geometry based on some other geometry and some > parameters, coming from 'expressions'. > > In this way it is for example possible to create some kind of polygon > based on a point layer. > My goal: create rotated 'wedges/sectors' with a data-based rotation from a > point layer (talking about GSM 'beams' here), but (tricky part): size > depending on the current map scale... > > My plan to mimic this in a Geoserver WMS: > - have a point layer in postgis > - create a postgis function to create a wedge (taking the attribute in > account) > - create a SQL view layer which creates a geom by calling this function > > Question: is it possible for geoserver to 'insert' the scale (as being > requested in the WMS request) into this function-call as parameter. > Something like $SCALE or $SCALE_DENOMINATOR or so, which is to be replaced > by Geoserver BEFORE handling over the query to postgis? > > Looking into the docs[0], it looks like it would be possible with a > (client site added) parameter. But in this case the 'scale'-information > should come from the WMS-request-info (as it is not possible to change the > client apps for us). > > Mmm, now I am afraid this is maybe hard as it makes it impossible to > 'cache' this view... > > Anyone idea's? > > Regards, > > Richard Duivenvoorde > > > [0] https://docs.geoserver.org/stable/en/user/data/database/sqlview.html > > > > > > _______________________________________________ > Geoserver-users mailing list > > Please make sure you read the following two resources before posting to > this list: > - Earning your support instead of buying it, but Ian Turton: > http://www.ianturton.com/talks/foss4g.html#/ > - The GeoServer user list posting guidelines: > http://geoserver.org/comm/userlist-guidelines.html > > If you want to request a feature or an improvement, also see this: > https://github.com/geoserver/geoserver/wiki/Successfully-requesting-and-integrating-new-features-and-improvements-in-GeoServer > > > [email protected] > https://lists.sourceforge.net/lists/listinfo/geoserver-users > -- Ian Turton
_______________________________________________ Geoserver-users mailing list Please make sure you read the following two resources before posting to this list: - Earning your support instead of buying it, but Ian Turton: http://www.ianturton.com/talks/foss4g.html#/ - The GeoServer user list posting guidelines: http://geoserver.org/comm/userlist-guidelines.html If you want to request a feature or an improvement, also see this: https://github.com/geoserver/geoserver/wiki/Successfully-requesting-and-integrating-new-features-and-improvements-in-GeoServer [email protected] https://lists.sourceforge.net/lists/listinfo/geoserver-users
