AW: [OpenLayers-Users] WMS-C/TMS and WMTS

[Phil Scadden]

> Would be possible to show us the code snippets for TMS maptiles
> without a server using the file created by maptiler?
>
> I like to see e.g. overlay_getTileURL /  (your custom getURL to fetch
> the tile) function  with file protocol (file://) in local directory.
>

Sure. tms tiles in a directory on disk has relative of 
Content/outputs/Magnetics
lay.imageBounds is tms bounds in lat/long (so dproj is a 4326 projection 
and proj is 900913)
lay.minZoom and maxZoom and the zoom you specified when you created the 
TMS. I could do this the
"proper" OL way but its a pain to calculate and setup. This works just fine.

             tmsLayer = new OpenLayers.Layer.TMS(lay.name, 
'Content/outputs/', {
                 type: 'png',
                 alpha: true,
                 serviceVersion: '',
                 layername: 'Magnetics',
                 tileExtent: new OpenLayers.Bounds(lay.imageBounds.left, 
lay.imageBounds.bottom, lay.imageBounds.right, 
lay.imageBounds.top).transform(dproj, proj),
                 mapMinZoom: lay.imageMinZoom,
                 mapMaxZoom: lay.imageMaxZoom,
                 getURL: tms_getTileURL,
                 displayOutsideMaxExtent: true,
                 zoomOffset: 0,
                 isBaseLayer: lay.baselayer
             });

the getURL to use is:
function tms_getTileURL(bounds) {
     adjustBounds(bounds, this.maxExtent);
     var res = this.map.getResolution();
     var x = Math.round((bounds.left - this.maxExtent.left) / (res * 
this.tileSize.w));
     var y = Math.round((bounds.bottom - this.tileOrigin.lat) / (res * 
this.tileSize.h));
     var z = this.map.getZoom();
     z = this.serverResolutions != null ? 
OpenLayers.Util.indexOf(this.serverResolutions, res) : z + this.zoomOffset;
     if (this.tileExtent.left > this.tileExtent.right) {
         var b1 = new OpenLayers.Bounds(this.tileExtent.left, 
this.tileExtent.bottom, this.map.maxExtent.right, this.tileExtent.top);
         var b2 = new OpenLayers.Bounds(this.map.maxExtent.left, 
this.tileExtent.bottom, this.tileExtent.right, this.tileExtent.top);
         if ((b1.intersectsBounds(bounds) || 
b2.intersectsBounds(bounds)) && z >= this.mapMinZoom && z <= 
this.mapMaxZoom) {
             return this.url + this.serviceVersion + "/" + 
this.layername + "/" + z + "/" + x + "/" + y + "." + this.type;
         } else {
             return "images/none.png";
         }
     } else {
         if (this.tileExtent.intersectsBounds(bounds) && z >= 
this.mapMinZoom && z <= this.mapMaxZoom) {
             return this.url + this.serviceVersion + "/" + 
this.layername + "/" + z + "/" + x + "/" + y + "." + this.type;
         } else {
             return "images/none.png";
         }
     }
}

Note that instead of returning a null image, I am looking at css that 
gives blank tile when tileurlload fails. If I can get this to work, then 
it is easily to have merge TMS into one mozaic which dont have complete 
tile coverage.


-- 
Phil Scadden, Senior Scientist GNS Science Ltd 764 Cumberland St, 
Private Bag 1930, Dunedin, New Zealand Ph +64 3 4799663, fax +64 3 477 5232

Notice: This email and any attachments are confidential. If received in error please destroy and immediately notify us. Do not copy or disclose the contents.