topic Re: on-the-fly projections api 2.0 vs 2.1 w/ Tiled Map Service in ArcGIS JavaScript Maps SDK Questions

on-the-fly projections api 2.0 vs 2.1 w/ Tiled Map Service

GregCorradini — Fri, 17 Dec 2010 02:15:56 GMT

Hello,
Has anything changed from JS API 2.0 to 2.1 in regards to on-the-fly projections with TiledMapServiceLayers? Last time I checked only the dynamic map service layers used on-the-fly projections based on the map.spatialReference. Tiled map services didn't do on-the-fly projections. But this wep map is making me think that I missed something. As far as I can tell the only difference in the linked example is the 2.0 api. Was that feature supported in 2.0 with tiles?

Re: on-the-fly projections api 2.0 vs 2.1 w/ Tiled Map Service

derekswingley1 — Fri, 17 Dec 2010 15:01:02 GMT

Hi Greg,

I put together the app you referenced. There's no on-the-fly projection of a tiled map service. What makes you think there is? Tiled map services cannot be re-projected on the fly via the web APIs.

Re: on-the-fly projections api 2.0 vs 2.1 w/ Tiled Map Service

GregCorradini — Fri, 17 Dec 2010 19:29:02 GMT

Thanks for the reply Derek,

That's what I thought. I don't understand how your toggling works then. Where in your code are you switching projections for the topo and streets tiles? They are in two different projections. I've walked through the execution but I'm missing something obvious then.

Re: on-the-fly projections api 2.0 vs 2.1 w/ Tiled Map Service

derekswingley1 — Fri, 17 Dec 2010 20:11:41 GMT

All the base map services are in web mercator. Here are the urls for each service:

http://services.arcgisonline.com/ArcGIS/rest/services/World_Topo_Map/MapServer
http://services.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer
http://services.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer

And here's the JS file that is using them: http://apps4ca.appspot.com/js/np_app.js

Re: on-the-fly projections api 2.0 vs 2.1 w/ Tiled Map Service

GregCorradini — Fri, 17 Dec 2010 20:29:14 GMT

duh. I see my mistake. I assumed your streets map service was coming from here (where mine was) and that service is GCS_WGS_1984. My bad. Thanks for the heads up and the code. I'm going to use a lot of it 🙂

Re: on-the-fly projections api 2.0 vs 2.1 w/ Tiled Map Service

derekswingley1 — Fri, 17 Dec 2010 20:47:05 GMT

Glad to help, have fun!