[OpenLayers-Users] Greetings and help (open layers layers)

[Christopher Schmidt]

On Thu, Mar 13, 2008 at 12:53:19PM +0000, Cole Henley wrote:
> Hi all
> 
> New to this list after spending some time working on Open Layers (with
> the glamorous assistance of Andrew Larcombe). Work as a webbie for a
> governement heritage agency in Scotland and looking to move to OL for
> the delivery of our map-based services.
> I am primarily a front-end developer/designer (back and front end) but
> no coding pro so able to get head round a lot of OL (love the ability
> to control with CSS) but hitting a few brick walls which wanted to
> sound out to the mailing list in the next couple of days if that is
> okay.
> 
> First up is a question about how layers are styled and displayed in OL.
> I have been thinking about using CSS to insert a transparent PNG over
> the base map layer to provide some basic watermarking at the
> client-side but always seems to end up with the image over the map
> features, irrespective of the z-index set (looking at the OL FAQ these
> should be determined through the z-index property[1]).
> 
> Can anyone advise on how best to use style (with CSS or JS) to insert
> an image between the map layer and feature layers?

There is no good way to do this. The reason is that in order to work in
the same 'z-index plane' (cross browser), you have to be *inside* the
LayerContainer div, inside the map, and when you do that, your images
used for ater marking become 'draggable': when the layer container div
is dragged, all of the items inside of it move. 

I can't think of a workaround for this off the top of my head.

Regards,
-- 
Christopher Schmidt
MetaCarta