[OSGeo-Discuss] WMS and layer stacking.

Christopher Schmidt crschmidt at crschmidt.net
Wed Sep 15 07:40:30 PDT 2010


On Wed, Sep 15, 2010 at 04:33:04PM +0200, P Kishor wrote:
> On Wed, Sep 15, 2010 at 3:59 PM, Ian Turton <ijturton at gmail.com> wrote:
> > On Tue, Sep 14, 2010 at 2:59 PM, Bob Basques
> > <Bob.Basques at ci.stpaul.mn.us> wrote:
> >> All,
> >>
> >> does anyone know if there is a layer hierarchy setting in the WMS service,
> >> which layers are on top of which layers (Z value=)?
> >>
> >
> > There is an "opaque" hint in the capabilities document that suggests
> > that the layer should be a base layer. Other than that the layers are
> > just drawn in the order the client requests them and there is no
> > implied ordering from the capabilities file. For example GeoServer
> > returns the layers in alphabetical order by namespace then layer name.
> >
> 
> 
> I was quite under the belief that the layers were requested, delivered
> and drawn in the order they appeared in the map.addLayers([array])
> invocation.

You're discussing an implementation (OpenLayers), with multiple requests to
the WMS server being stacked in the client. 

This discussion is about the WMS "API".

WMS draws layers from bottom to top, from the beginning of the list in the
'layers' param to the end.

 layers=foo,bar,baz

will put foo first, then bar, then baz.

-- Chris

> 
> > Ian
> > --
> > Ian Turton
> > _______________________________________________
> > Discuss mailing list
> > Discuss at lists.osgeo.org
> > http://lists.osgeo.org/mailman/listinfo/discuss
> >
> 
> 
> 
> -- 
> Puneet Kishor http://www.punkish.org
> Carbon Model http://carbonmodel.org
> Charter Member, Open Source Geospatial Foundation http://www.osgeo.org
> Science Commons Fellow, http://sciencecommons.org/about/whoweare/kishor
> Nelson Institute, UW-Madison http://www.nelson.wisc.edu
> -----------------------------------------------------------------------
> Assertions are politics; backing up assertions with evidence is science
> =======================================================================
> _______________________________________________
> Discuss mailing list
> Discuss at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/discuss

-- 
Christopher Schmidt
Web Developer



More information about the Discuss mailing list