# What kind of Coordinate system is Cesium using?

**URL:** <https://community.cesium.com/t/what-kind-of-coordinate-system-is-cesium-using/3073>\
**Category:** CesiumJS\
**Created:** [September 16, 2015, 9:44pm UTC](https://community.cesium.com/t/what-kind-of-coordinate-system-is-cesium-using/3073 "2015-09-16T21:44:40Z")\
**Posts on this page:** 7\
**Page:** 1

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**Author:** ![wilson1256](https://avatars.discourse-cdn.com/v4/letter/w/dfb087/32.png) [@wilson1256](https://community.cesium.com/u/wilson1256)\
**Post date:** [September 16, 2015, 9:44pm UTC](https://community.cesium.com/t/what-kind-of-coordinate-system-is-cesium-using/3073/1 "2015-09-16T21:44:40Z")

</div>

I am loading a KML file into Cesium and trying to load the KML point position by clicking on it. I am using the code below to get the coordinate：

var handler = new Cesium.ScreenSpaceEventHandler(viewer.scene.canvas); handler.setInputAction(function(click) {

var pickedObject = viewer.scene.pick(click.position);   
var positionUnformat = pickedObject.id.position.getValue(viewer.clock.currentTime);

}, Cesium.ScreenSpaceEventType.LEFT\_DOUBLE\_CLICK);

However, the coordinate i got from this code seems like to be different from what is actually written in the KML file. It is not the true position and altitude of the real world. How can I get the position coordinate correct? Or I have to transform the value to get the right answer?

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**Author:** ![falco103](https://avatars.discourse-cdn.com/v4/letter/f/e495f1/32.png) [@falco103](https://community.cesium.com/u/falco103)\
**Post date:** [September 17, 2015, 1:14am UTC](https://community.cesium.com/t/what-kind-of-coordinate-system-is-cesium-using/3073/2 "2015-09-17T01:14:32Z")

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Cesium uses radians by default for angular measurements. You'll need to convert the coordinates you see using Cesium.Math.toDegrees(yourRad)

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**Author:** ![Matt\_Amato](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/matt_amato/32/1993_2.png) [@Matt\_Amato](https://community.cesium.com/u/Matt_Amato)\
**Post date:** [September 17, 2015, 1:24am UTC](https://community.cesium.com/t/what-kind-of-coordinate-system-is-cesium-using/3073/3 "2015-09-17T01:24:40Z")

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The position you are getting is in Earth-fixed Cartesian coordinates, so those numbers are in meters. You can easily convert this to longitude/latitude/height. See the “Show Cartographic Position on Mouse Over” example for the details: [http://cesiumjs.org/Cesium/Apps/Sandcastle/index.html?src=Picking.html&label=Showcases](http://cesiumjs.org/Cesium/Apps/Sandcastle/index.html?src=Picking.html&label=Showcases)

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<div class="post-metadata">

**Author:** ![wilson1256](https://avatars.discourse-cdn.com/v4/letter/w/dfb087/32.png) [@wilson1256](https://community.cesium.com/u/wilson1256)\
**Post date:** [September 18, 2015, 3:24pm UTC](https://community.cesium.com/t/what-kind-of-coordinate-system-is-cesium-using/3073/4 "2015-09-18T15:24:44Z")

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Hi Matthew,  
Thanks for your answer. I can get the proper longitude and latitude right now, however I still can not get the correct altitude. The value of the altitude is always zero. Do I have to load the height map by setting something before I can get the value of KML file altitude?

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**Author:** ![Matt\_Amato](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/matt_amato/32/1993_2.png) [@Matt\_Amato](https://community.cesium.com/u/Matt_Amato)\
**Post date:** [September 22, 2015, 12:26am UTC](https://community.cesium.com/t/what-kind-of-coordinate-system-is-cesium-using/3073/5 "2015-09-22T00:26:56Z")

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Is the data being clamped to the ground? Otherwise the height should be correct. If it’s being clamped, then the value is expected to be 0. Can you post the Placemark snippet and style from the KML file?

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<div class="post-metadata">

**Author:** ![wilson1256](https://avatars.discourse-cdn.com/v4/letter/w/dfb087/32.png) [@wilson1256](https://community.cesium.com/u/wilson1256)\
**Post date:** [September 22, 2015, 3:40pm UTC](https://community.cesium.com/t/what-kind-of-coordinate-system-is-cesium-using/3073/6 "2015-09-22T15:40:24Z")

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Yes, here is the whole part of the KML file omitted the description part:

\<kml xmlns:gx="[http://www.google.com/kml/ext/2.2](http://www.google.com/kml/ext/2.2)" xmlns:atom="[http://www.w3.org/2005/Atom](http://www.w3.org/2005/Atom)" xmlns="[http://www.opengis.net/kml/2.2](http://www.opengis.net/kml/2.2)"\>  
&nbsp;&nbsp;\<Document\>  
&nbsp;&nbsp;&nbsp;&nbsp;\<Folder\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\<name\>BusinessRule1\</name\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\<Style id="BR1Stl"\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\<IconStyle\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\<Icon\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\<href\>blackcircle.png\</href\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\</Icon\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\<scale\>0.7\</scale\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\</IconStyle\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\<LabelStyle\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\<scale\>0.8\</scale\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\</LabelStyle\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\</Style\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\<Placemark id="103215"\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\<name\>51-AIRPORTSGIS-103215\</name\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\<styleUrl\>#BR1Stl\</styleUrl\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\<description\>....\</description\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\<Point\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\<altitudeMode\>absolute\</altitudeMode\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\<coordinates\>-76.43594397,36.77823129,33.3030576\</coordinates\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\<extrude\>1\</extrude\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\</Point\>  
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;\</Placemark\>  
&nbsp;&nbsp;&nbsp;&nbsp;\</Folder\>  
&nbsp;&nbsp;\</Document\>  
\</kml\>

Is the data clamped to the ground? How can I know that?

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<div class="post-metadata">

**Author:** ![Scott\_Reynolds](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/scott_reynolds/32/2014_2.png) [@Scott\_Reynolds](https://community.cesium.com/u/Scott_Reynolds)\
**Post date:** [September 23, 2015, 3:13pm UTC](https://community.cesium.com/t/what-kind-of-coordinate-system-is-cesium-using/3073/7 "2015-09-23T15:13:26Z")

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absolute indicates that the data is not to be clamped to the ground. See [this](https://developers.google.com/kml/documentation/altitudemode) for more information.

Scott