[Qgis-developer] Question on inverted polygon renderer

[Bernhard Ströbl]

Hi Hugo,

let me explain: I use mapcache to preproduce tiles of my background 
layers rendered by QGIS server. Thus sometimes labels get cut because 
they are rendered too close to the edge of the requested map.
I was attracted by Régis "Label features of layers only for objects 
intersecting the mask region" and was thinking if one could use that to 
address my problem, especially if it goes into core (needs to be for 
server I reckon). There won't be a dedicated mask layer, of course, but 
I imagined server creating the mask feature otf from the bbox parameter 
of the GetMap request (minus a distance set in OWS server tab).
If you integrate this into core and there might be a chance to use it as 
I described I would be happy if you integrated it in a way that would 
allow to enhance QGIS server to use it.

Bernhard

Am 17.06.2014 10:22, schrieb Hugo Mercier:
> Hi,
>
> Le 17/06/2014 09:32, Régis Haubourg a écrit :
>> Hi Bernard,
>> plugin is coming this week I think.
>
> Yes, it is already available at https://github.com/Oslandia/mask_plugin
> A 1.0 version for the official qgis repository is on its way.
>
>>
>> Bernhard Ströbl wrote
>>> Thinking about QGIS server: Would there be a chance to use what you
>>> describe to keep labels staying away from the edge of the requested map?
>>>
>>> Bernhard
>>
>> current implementation adds a In_mask(srid) expression, that can be used
>> anywhere in style or labeling settings. If QGIs server fill current mask
>> geometry with a bbox, slightly smaller than true extent, you will avoid
>> drawing labels to close from the edges. I'm not sure this is the best design
>> option, it sounds more like a hack to me.
>> I will let Hugo explain detailed implementation.
>
> Well, I don't know exactly what is the problem with the labeling part of
> the server. This label filtering feature has not been designed for such
> a use-case. The current implementation of "atlas with mask" relies on
> signals that are catched within a plugin to update the mask layer.
> We could imagine something similar for the server, but I agree that
> would be a hack.
>
> The problem you have might be somehow related to how qgis clips vectors
> before rendering them, as Nyall pointed out
> (http://hub.qgis.org/issues/9757)
>
> _______________________________________________
> Qgis-developer mailing list
> Qgis-developer at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/qgis-developer
>


__________ Information from ESET Mail Security, version of virus signature database 9957 (20140617) __________

The message was checked by ESET Mail Security.
http://www.eset.com