topic How to change the projection when load esri dynamic map? in ArcGIS API for Flex Questions

How to change the projection when load esri dynamic map?

XintaoLiu — Thu, 11 Oct 2012 17:20:59 GMT

For example, if I want load this as base map:
<layer label="Topo" type="tiled or dynamic" visible="false" alpha="1" url="http://server.arcgisonline.com/ArcGIS/rest/services/World_Topo_Map/MapServer"/>

is it possible to change the projection coordinates system, e.g. to from Mercator to North Pole? Thanks!

Re: How to change the projection when load esri dynamic map?

XintaoLiu — Fri, 12 Oct 2012 13:07:05 GMT

Does anyone have any clues? Thank you!

Re: How to change the projection when load esri dynamic map?

BjornSvensson — Sat, 13 Oct 2012 05:28:28 GMT

is it possible to change the projection coordinates system, e.g. to from Mercator to North Pole?

No, you cannot change the projection of the tiled maps. The tiles have already been created, and there is no on-the-fly projection of them on the client.

Re: How to change the projection when load esri dynamic map?

XintaoLiu — Sat, 13 Oct 2012 12:34:48 GMT

No, you cannot change the projection of the tiled maps. The tiles have already been created, and there is no on-the-fly projection of them on the client.

Thanks for your reply. It's reasonable that we cannot change the projection of the tiled maps. But, how about the dynamic maps and feature layers? Can we change the projection on the client? Thank you!

Re: How to change the projection when load esri dynamic map?

RhettZufelt — Tue, 16 Oct 2012 14:53:04 GMT

I have not tried with "North Pole", but if you load "your" basemap intially OR set the WKID to North Pole, then you should be able to load the ESRI basemap if you load as type="dynamic". That way, it won't be limited to the pre-rendered tiles, and can project it on the fly. It is slower than loading as tiled, but it should put it in the correct location.

Just make sure the WKID is set BEFORE you load the ESRI map.

R_

Re: How to change the projection when load esri dynamic map?

BjornSvensson — Tue, 16 Oct 2012 15:14:13 GMT

I have not tried with "North Pole", but if you load "your" basemap intially OR set the WKID to North Pole, then you should be able to load the ESRI basemap...

I think that's a bad idea for several reasons, but the main one is probably that there are no tiles covering the poles. The Web Mercator projection does not cover the whole world, the max latitude shown is about 85 degrees north.

Re: How to change the projection when load esri dynamic map?

RhettZufelt — Tue, 16 Oct 2012 15:37:12 GMT

I think that's a bad idea for several reasons, but the main one is probably that there are no tiles covering the poles. The Web Mercator projection does not cover the whole world, the max latitude shown is about 85 degrees north.

Like I said, I hadn't tested it with North Pole, and now that I look, I see the ESRI topo service doesn't cover anything north of Greenland, tiled or not.

Bjorn,

Curious what the "other" reasons that make this a bad idea are? Is there a "better" method for pulling as ESRI basemap service into a map that is other than mercator?

R_

Re: How to change the projection when load esri dynamic map?

XintaoLiu — Wed, 17 Oct 2012 14:13:18 GMT

Like I said, I hadn't tested it with North Pole, and now that I look, I see the ESRI topo service doesn't cover anything north of Greenland, tiled or not.

Bjorn,

Curious what the "other" reasons that make this a bad idea are? Is there a "better" method for pulling as ESRI basemap service into a map that is other than mercator?

R_

Thank you so much for your replies! I appreciate that. It worth trying the solution to see the loading speed.

I am also curious that whether ESRI basemap services have other projections other than Mercator? If yes, it should be cool!