topic Re: Load tiles of map through UTM projection in Map Projections Questions

Load tiles of map through UTM projection

Maryameslamy — Wed, 17 Feb 2016 06:52:15 GMT

Hi Dear

I want to Use UTM projection to Load My Tiles. I did it formerly through Mercator projection. This is my code to create tiles in mecator projection.

private const double cornerCoordinate = 20037508.3427892

private const int WKID = 102100;

TileInfo = new TileInfo()

{

Height = 256,

Width = 256,

Origin = new MapPoint(-cornerCoordinate, cornerCoordinate) { SpatialReference = new ESRI.ArcGIS.Client.Geometry.SpatialReference(WKID) },

Lods = new Lod[20]

};

double resolution = cornerCoordinate * 2 / 256;//180.0000 * 2 / 256;

the values in cornerCoordinate and WKID parameters is specialized for mercator projection. So, and it is my questions:

1: what are the values for cornercoordinate and WKID for UTM projection?

Unfortunately, I can not achieve suitable information in the net, please, Guide me.

thanks in advance

Re: Load tiles of map through UTM projection

NeilAyres — Wed, 17 Feb 2016 07:32:50 GMT

What is WKID 102100?

I can find no reference to it in my docs. The closest 102101 and up is a bunch of coordsystems for Norway.

As for the corner coordinate, only you would know that?

Worldwide UTM zones (WGS84 based) are numbered 326 + zone number for the northern hemisphere and 327 + zone number for us in the south.

Re: Load tiles of map through UTM projection

Maryameslamy — Wed, 17 Feb 2016 07:47:01 GMT

thanks Dear Neil

WKID = 102100 is an special reference for mercator projection. fortunately this WKIDworks correctly.

these links are related to it.

ESRI:102100: SR-ORG Projection -- Spatial Reference

http://www.faqoverflow.com/gis/253.html

I will appreciate you, if you clarify corner coordinate conception and its value (20037508.3427892) for me.

thanks in advance

Re: Load tiles of map through UTM projection

NeilAyres — Wed, 17 Feb 2016 10:12:31 GMT

So 102100 is actually 3857 and has been like that since v10.0. That's why I can't find a reference to it.

So what is this :

(20037508.3427892)

Is that one big long number with 7 decimals or actually 2 numbers separated by ".".

A "Coordinate" implies at least 2 numbers, an X & a Y.

And which corner is it? LL, LR, UL, UR???

Re: Load tiles of map through UTM projection

Maryameslamy — Wed, 17 Feb 2016 10:44:40 GMT

thanks a lot.

yes, you are right. these two values are equal.

please, look at this link

arcgis-toolkit-sl-wpf/WebTiledLayer.cs at master · Esri/arcgis-toolkit-sl-wpf · GitHub

that is a remarkable link to get beneficial information for loading tile layer.

in this code line

this.FullExtent = new ESRI.ArcGIS.Client.Geometry.Envelope(-cornerCoordinate, -cornerCoordinate, cornerCoordinate, cornerCoordinate)

{

SpatialReference = new SpatialReference(WKID)

};

and so it is equal to (Xmin,Ymin,Xmax,Ymax).

(Xmin,Ymin) Left Up

(Xmax,Ymax) Right Down

But as mentioned in this link, the values of cornerCoordinate and WKID are set only mecator projection. I do not handle this code for UTM projection.

Best regards

Mary