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My geoserver is providing few overlayers with specific informations such as poi's or fire-hydrants. I'm using scale dependent styling, so it's not rendering this features above specified scale, but it still tries to render it and returns empty tiles. I've found WMS 1.3.0 includes MaxScaleDenominator and MinScaleDenominator tags, which can be provided in the getCapabilities result to show the optimum visualization ranges for each layer. I want to use it to learn my application not to ask about tiles above specified scale (cause they're empty there) so it will improve performance and reduce bandwidth usage.

I searched all geoserver properties (general, layer, caching) and I was not able to find any place to set this feature up, so I don't think there is some place in web-gui (or there is??), but maybe there is some resolution to write it somewhere in configuration files?

This is some link to my geoserver, e.g. layer is osm:Hydranty_active

After some investigation I've found that in layer osm:Hydranty_active served by WMS this information is included, but the same layer served via gwc don't have it, so trouble will be with GWC not Geoserver

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  • I've found WMS 1.3.0 includes MaxScaleDenominator and MinScaleDenominator tags, which can be provided in the getCapabilities result to show the optimum visualization ranges for each layer. that's not the purpose of those elements, it's not about optimum, it's about the scales at which the data will show a map
    – nmtoken
    Commented Jun 6, 2019 at 16:20

2 Answers 2

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The scale limits which are used in SLD should be converted automatically into MinScaleDenominator/MaxScaleDenominator with WMS 1.3.0 and into ScaleHint in WMS 1.1.1. You can read examples from this demo server:

http://demo.opengeo.org/geoserver/wms?service=WMS&request=GetCapabilities&version=1.3.0

http://demo.opengeo.org/geoserver/wms?service=WMS&request=GetCapabilities&version=1.1.1

Scale range hints are per layer and they are included into the document if there is some scale range that does not display a layer with any style that is attached to the layer. If you have a special rule for fire hydrants on a general poi layer (draw capitals at all scales but use MaxScaleDenominator=20000 for fire hydrants) it is not possible to read the fire hydrant's scale range from GetCapabilities. However, it is possible to get that information by downloading the whole SLD with the GetStyles request

http://demo.opengeo.org/geoserver/wms?service=WMS&request=GetStyles&version=1.1.1&layers=osm:water_lines_low_zoom

Some background about GeoServer and scale hints is in http://jira.codehaus.org/browse/GEOS-5830.

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  • Thanx - Very usefull - I'll check it out cause this could be resolution.
    – Jendrusk
    Commented Oct 8, 2014 at 11:08
  • The trouble is not in place I was looking for it. Thanx 4 pointing that geoserver is working properly.. I have to write some issue to GWC.
    – Jendrusk
    Commented Nov 6, 2014 at 9:04
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There is no such feature, it's up to your client to look into the WMS capabilities document and get the valid scale ranges from there. You'll need a recent enough version of GeoServer to find the limits in there (I'm positive they are in 2.6.x, not sure about 2.5.x)

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  • Thanx - I know that's up to my client - I was asking about geoserver side, cause even if I'm using scale dependent styling there is no limits in capabilities. Maybe it's case of version (using 2.5). Added some links to my geoserver.
    – Jendrusk
    Commented Oct 8, 2014 at 10:59

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