[OpenLayers-Dev] initResolutions issue (reformated...)

[Sébastien Roch]

ok I'll give more details this week-end, I have no much time now. I
just can tell that even if minScale/maxScale settings work, it doesn't
arrange the problem with the initialization of the layer resolutions.
I use my own controls for zooming and layer switching, but that
doesn't matter : some values are not properly set with the
configuration below, and are quite important in my sense.
I'll let you know more this week-end,
cheers,
Sebastien

On Nov 29, 2007 8:45 PM, Eric Lemoine <eric.c2c at gmail.com> wrote:
> On Nov 29, 2007 4:50 PM, Sébastien Roch <roch.sebastien at gmail.com> wrote:
> > Hi dev,
> > I'm working on a project with a lot of layers, which only appear at
> > some levels regarding each layer.
> > I got some problems with my map and layer configurations, and after
> > code reviewing, want to expose you the problem :
> > this is my map options:
> > {       controls : []
> >         units : "m",
> >         projection : "EPSG:21781",
> >         maxExtent: new OpenLayers.Bounds(484250,63254,837789,299902),
> >         scales: [1924725,300000,150000,60000,30000,15000,7500,6000,4000,2000],
> >         numZoomLevels : 10,
> >         theme : null // disable default theme (or default css is imported)
> > };
> >
> > and the options of a ka-map layer :
> > {       format : "image/png",
> >         buffer: 1,
> >         scales : [150000,60000,30000,15000,7500,6000,4000,2000],
> >         isBaseLayer: false,
> >         visibility: false
> > }
>
> One unrelated comment: shouldn't format be a param as opposed to an
> option? (I'm not sure about ka-map, for for a wms layer, format is a
> param not an option)
>
> Also, you use isBaseLayer:false. Do you really want that?
>
>
> > So what I want is having this ka-map layer displayed only at these
> > given scales. After having checked the code, I understood I can't just
> > use the minScale and maxScale options : as the option scales is set
> > for the map, the layer will inherit of it, and we jump then in a
> > if-bloc which doesn't care of minScale/maxScales... (see
> > Layer.js/initResolutions)
>
> I just looked at initResolutions() and actually the layer's options
> (resolutions, scales, maxScale, minScale, etc.) have precedence over
> the map's options. So, you should be able to set minScale and maxScale
> at the layer level.
>
> > I first thought I could repair that, but the problem is more tricky as
> > it appears :
> > the config above seems to work, but... if you zoomin to last zoom
> > level and type "myLayer.getResolution()", it returns "undefined"...
> > This because "map.getZoom" is taken as index to get the resolution of
> > the layer  -  but there is no resolution for this index in its
> > resolutions array!
>
> What control do you use for zooming?
>
> If you use the zoombar you should notice a change in its number of
> zoom levels when you switch your base layer. Do you?
>
> Could you tell more about your setup? In part. do you have both
> baselayers and overlays?
> --
> Eric
>