[ka-Map-users] selecting multiple layers

David Bitner osgis.lists at gmail.com
Thu Jul 28 09:51:36 EDT 2005

What version of ka-map are you using?  In the cvs version there is the
option to display your layers as vertically stacked.  What this does
is if you have your mapfile set to provide transparent pngs is it
renders every group that you have defined in your mapfile to be
rendered separately.  The end effect is instant on and off when you
check or uncheck your groups.  Do note that only those layers that are
not marked as a group are dragged around by the mouse, the other
layers then fill in once you've stopped.

On 7/26/05, Lorenzo Becchi <lorenzo at ominiverdi.com> wrote:
> Hi,
> I really apreciate your work with KaMap.
> We tried to do our personal version here:
> We developed our system to check or unckeck layers visibility. You have
> to check layers an click on "ricarcola" button to see changes. Acting
> like this it works great.
> Problems arise when you zoom in or out in a map that shows certain
> layers at certain scales.
> In our case a layer called CTR is shown only under 1:500.000 resolution.
> When you zoom in twice (1:250.000) in the center of Lucca (LU) province
> it has to appear a tile for the Tecnical Regional Map (CTR) because we
> set it visible in the map at this zoom factor. You can see  CTR in the
> Legend but the tile doesn't appear.
> If you move (scroll?) in the map, far from that point, and you came
> back to the LU center the tile appears. It appears also if you click on
> "ricarcola" button.
> What we did:
> 1) create a page ("layers.php") that calls the mapserver each time a
> zoom is clicked (or by default) and gives back a list of visible layers
> at the new zoom factor (js function getLayers()). This list is paired
> with the javascript session list and we finally get which layer is on
> and which layer is off (js function setLayersCsv()).
> the result is shown right side of "zoom out" button ("Layerz").
> 2) we modified js function setTile() to pass onLayers variable set by
> setLayerCsv().
> we where expecting that setLayerCsv was as fast as the
> zoomIn->initializeLayers->setTile series but first tiles coming still
> maintain "old" onLayers. After a while tiles are coming with the right
> combination of layer.
> We tried to put a delay in zoom functions after setLayerCsv() and
> before initializeLayers() but it has to be a long delay (6 seconds at
> least) to work fine.
> any suggestions?
> I hope this explication is understandable.
> thanks
> Lorenzo
> _______________________________________________
> ka-Map-users mailing list
> ka-Map-users at lists.maptools.org
> http://lists.maptools.org/mailman/listinfo/ka-map-users

More information about the ka-Map-users mailing list