We just put up another “demo” site – this time working with Sanborn to provide visualization for their wildfire risk model outputs they have created for the Texas Forest Service. For information on the data, there is contact information on the “About” tab.
From a technical stand-point, we added a few new features to this viewer…
Dealing with Multiple Tile Layers
The viewer is pulling in multiple tile services, representing multiple layers in a map, as opposed to a single “fused” tile layer. This is the first time I’ve implemented multiple layers using the ArcGIS Server Tile Cache code, and it turns out it’s currently a bit of a pain. For this site, we’ve got 7 tile layers, and to do that with the current tile server code, I needed to create 7 map services (mxd’s), and then configure 7 tile services in the TileServer. Clearly this should be streamlined. For example, the url http://204.133.225.164/tileservice/txfirewfsi/023131001.ashx pulls a specific tile from the txfirewfsi tile service. (shown below)
However, I’m thinking that it would be nice to be able to add a layer name in the url -’parcels’ in this case - http://204.133.225.164/tileservice/txbasemap/parcels/023133.ashx. This way you could specify the fused tiles, or just a specific layer.
Adjusting Layer Transparency
This was easy, if not obvious. Adding in a Dojo.slider, and hooking up some events was pretty simple. However, it turns out that changing the .Opacity property of a VETileSourceSpecification has no effect after the layer has been added to map. Instead you need to delete the layer and re-add it with the new opacity. Since the browser is caching the tiles, this is actually very fast.
Virtual Earth 3D
This was also the first time I tried throwing things into 3D mode. It took a few quick tweaks in the javascript, and some different CSS for the markers, but for the most part – it “just worked”.
There are a few issues with the dojo menus that I’m going to sort out so I’ll save the Url for the 3d page until that’s dialed.
So, this took about 3 days to pull together — if you are looking under the covers, the code is VERY “demo” and has some issues – there are a few weird things with the layer list checkboxes and I have not really tested in IE7, and all bets are off with IE6. I’d love to hear thoughts & ideas though.
