[Tilecache] TC called if OL maxextent bigger than a particular layer's ?

[Eric Lemoine]

On Wednesday, June 23, 2010, Yves Moisan <yves.moisan at boreal-is.com> wrote:
>
>
> Right.
>
> Using a fake baselayer might be a workaround.
>
>
> Hi Eric,
>
> Thanx for chiming in.  You mean using a dummy base layer for which I would not have a TC defined ?

Yes.

new OpenLayers.Layer("_dummy_", {
    isBaseLayer: true,
    displayInLayerSwitcher: false,
    maxExtent: ...
});

(maxExtent can also be defined in the map options.)

> The idea basically is to still show the TC layer, for the extent it is defined, and not request unecessary (in fact undefined) tiles.

No tiles outside the TC layer's maxExtent will be requested.

> I understand I could show features on a super (dummy) base layer and maybe make the TC baselayer available at a certain scale

Just in case this is unclear: in the workaround I'm suggesting the
dummy base layer is a regular base layer (as defined above), and the
TC layer is an overlay.

> (though I wonder how seeding would work then : zoomLevel 0 would be 2 or 3 in reality), but I don't see how users can see the portion for which there is a tilecached layer.  I think we'll resort to defining a new OL map object altogether.

-- 
Eric Lemoine

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