[Qgis-developer] Feedbacks about Qgis Server

[Marco Bernasocchi]

On 11/15/2011 11:04 AM, Marco Hugentobler wrote:
> Hi Michael
>
>>> The issue with the different scales are really annoying, so why dont we
>>> make the 96 dpi the default? Do you really think it is much slower?
>> Much slower, no, but I know for sure that decreasing tile sizes in one of
>> the first optimisation you do when you deliver map on the web. But I am not
>> sure decreasing DPI Tto 72 will make a big change though...
> QGIS (desktop) reads the dpi from the system and uses this dpi for the WMS
> requests. The WMS server cannot know about the clients dpi, therefore relies
> on the DPI parameter from the request.
>
> Is it possible to get the system DPI with javascript? If yes, we should use
> that value. If not, 96 seems better to me since most screens have a similar
> resolution (at least closer to 96 than 72).
maybe hacky but it might be an hint:
html:
     div id="dpiDiv" style="height:1in;"

script:
   alert(document.getElementById("dpiDiv").offsetHeight+"dpi");

Ciao Marco
> Regards,
> Marco
>
> Am Dienstag, 15. November 2011, 10.21:53 schrieb kimaidou:
>> Hi Andreas,
>>
>> Thanks for your answer.
>>
>>
>> 2011/11/14 Andreas Neumann<a.neumann at carto.net>
>>
>>> Many of the issues you raise here were also identified before or at the
>>> recent developer meeting. See also http://www.qgis.org/wiki/**
>>> QGISWebClientIdeas<http://www.qgis.org/wiki/QGISWebClientIdeas>
>> I have read this page quite "live" during the hackfest (it was a rainy
>> week-end down here in Montpellier). It has some very interesting things
>>
>>> The issue with the different scales are really annoying, so why dont we
>>> make the 96 dpi the default? Do you really think it is much slower?
>> Much slower, no, but I know for sure that decreasing tile sizes in one of
>> the first optimisation you do when you deliver map on the web. But I am not
>> sure decreasing DPI Tto 72 will make a big change though...
>>
>>> BTW - we already get 96dpi images, only OL seems to calculate the scale
>>> with 72dpi. We even try to detect the dpi when loading the client. Not
>>> sure if this works properly ... Thanks anyway for the hint. I will test
>>> it.
>> We spend half a day to understand why the layers did not have the correct
>> behaviour regarding min and maxScale. After some deep thinking, it appeared
>> it was relative to DPI . I can confirm for sure that using the OL option
>> OpenLayers.DOTS_PER_INCH = 96 and asking tiles in 96 DPI works. No more
>> problems (we tested it on a very complete and complex Qgis project)
>>
>>> An improved GetLegendGraphics with user configurable sizes is already
>>> requested and will be a paid development/improvement from Sourcepole.
>> Great news.
>>
>>> GetCapabilities improvements: at the meeting we decided to use a web map
>>> context (similar to GetCapabilities) but more configurable to transport
>>> settings we want, e.g the initial layer visibility, etc.
>> I think it is a good idea :)
>>
>>
>> Regards,
>> Michael
>