[OpenLayers-Dev] refreshing an image with new parameters

Marc Jansen jansen at terrestris.de
Wed Jan 6 04:48:50 EST 2010

Hi Art,

Maybe it would be best to create a new Layer-type for your problem. But 
using layerevents may help for now, e.g.:

graphic-events.register('moveend', window, function() {
  // set the URL of your layer

Hope that helps, it is untested.


Art Lembo wrote:
> I'm using Manifold GIS as a back-end GIS server.  It works really 
> great, except the WMS capabilities are horribly slow.  One thing that 
> is fast is the ability to generate an image of the GIS output by 
> passing a url to a Manifold IMS site: 
> var graphic = new OpenLayers.Layer.Image (
>    'My Map',
> 'http://blah,blah,blah/map.asp?[layers],[centerX],[centerY],[ScaleX],[ScaleY],[spatialSQL 
> process],etc...
> so, this works really fast (instantaneous), and gets me a layer inside 
> my OpenLayers site.  And, I can even pass it an analysis function and 
> it does that too.
> Now, when I zoom in or pan, obviously it just works with that initial 
> image (i.e. var graphic) that was grabbed from the init function.  So, 
> of course zoom-ins begin to pixelate rather quickly.
> I would like the ability to refresh the initial image every time I 
> zoom in or pan, using new centerX,centerY, and scales.  That is, some 
> function that gets thrown before the the image is redrawn.  
> I guess it is an image Refresh, but that doesn't quite do it.  My hope 
> is to:
> 1.  When the user zooms in I grab the new centerX, centerY, and scales 
> from the browser, and reconstruct the url to hit the server again and 
> show me an updated version, which will now be the zoomed in version of 
> the layers.
> Any advice?
> thanks!
> ------------------------------------------------------------------------
> _______________________________________________
> Dev mailing list
> Dev at openlayers.org
> http://openlayers.org/mailman/listinfo/dev


  Dipl.-Geogr. Marc Jansen
  - Anwendungsentwickler -

  terrestris GmbH & Co. KG
  Irmintrudisstraße 17
  53111 Bonn

  Tel:    ++49 (0)228 / 96 28 99 -53
  Fax:    ++49 (0)228 / 96 28 99 -57

  Email:  jansen at terrestris.de
  Web:    http://www.terrestris.de

  Amtsgericht Bonn, HRA 6835
  Komplementärin:  terrestris Verwaltungsgesellschaft mbH
  vertreten durch: Hinrich Paulsen, Till Adams  

More information about the Dev mailing list