[josm-dev] Automatic tiles downloading in WMSPlugin

[Petr Dlouhý]

On Fri, 19 Sep 2008 11:29:06 +0200, Bodo Meissner <bodo at bodo-m.de> wrote:

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> Petr Dlouhý wrote on 19.09.2008 08:49:
>> On Thu, 18 Sep 2008 22:51:47 +0200, Bodo Meissner <bodo at bodo-m.de>  
>> wrote:
>
>> How do you define the coordinates and resolution of the tile to be
>> downloaded?
>>
>>> It didn't change. I am still passing Bounds and pixelPerDegree and
>>> projection to grabber.
>
> Hello Petr,
>
> maybe I misunderstood an earlier message.
> I asked about the situation when I zoom out, then scroll to the desired
> place and then zoom in again. I do not want tiles in lower resolution
> for the new location. Second problematic case: I know one WMS server
> that returns white images when I zoom in too much, so I don't want any
> automatic download with this high resolution. IIRC you said that the
> image resolution for download is selected when the downloading starts
> and remains the same if I zoom in or out. So I tought I select the
> desired resolution by zooming in as necessary and then enable automatic
> downloading. Is this correct?
>

I add "change resolutin" button in context menu of the WMS layer. The
resolution is set (accordingly to current zoom level) on the
initialization of relevant layer or by that button.

>
> My question about Bounds and pixelPerDegrees is this: Where do the
> values come from? Do you use the bounds and pixelPerDegree values of the
> currently visible area on the screen as the old version did or do you
> use a fixed pixelPerDegree value and/or bounds rounded up to some fixed
> tile size that are selected at some specific time or event?
>

The pixelPerDegree is set when changing resolution and Bouds are counted
to fit in the images[][] - infinite (cycled) array of images of size
ImageSize×ImageSize.

>
>
> Bodo
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-- 
Petr Dlouhý