Alternatives considered
TODO(goto): go over this.
ARML is an XML-based data format to describe an interact with AR scenes.
ARML
<arml>
<ARElements>
<!-- register the Tracker to track a generic image -->
<Tracker id="defaultImageTracker">
<uri xlink:href="http://opengeospatial.org/arml/tracker/genericImageTracker" />
</Tracker>
<!-- define the artificial marker the Model will be placed on top of -->
<Trackable>
<assets>
<!-- define the 3D Model that should be visible on top of the marker -->
<Model>
<href xlink:href="http://www.myserver.com/myModel.dae" />
</Model>
</assets>
<config>
<tracker xlink:href="#defaultImageTracker" />
<src>http://www.myserver.com/myMarker.jpg</src{{dead link|date=October 2016 |bot=InternetArchiveBot |fix-attempted=yes }}>
</config>
<size>0.20</size>
</Trackable>
</ARElements>
</arml>
KML is an XML-based data format …
KML
<?xml version="1.0" encoding="UTF-8"?>
<kml xmlns="http://www.opengis.net/kml/2.2">
<Document>
<Placemark>
<name>CDATA example</name>
<description>
<![CDATA[
<h1>CDATA Tags are useful!</h1>
<p><font color="red">Text is <i>more readable</i> and
<b>easier to write</b> when you can avoid using entity
references.</font></p>
]]>
</description>
<Point>
<coordinates>102.595626,14.996729</coordinates>
</Point>
</Placemark>
</Document>
</kml>
GeoRSS ...
GeoRSS
<?xml version="1.0" encoding="utf-8"?>
<feed xmlns="http://www.w3.org/2005/Atom"
xmlns:georss="http://www.georss.org/georss">
<title>Earthquakes</title>
<subtitle>International earthquake observation labs</subtitle>
<link href="http://example.org/"/>
<updated>2005-12-13T18:30:02Z</updated>
<author>
<name>Dr. Thaddeus Remor</name>
<email>[email protected]</email>
</author>
<id>urn:uuid:60a76c80-d399-11d9-b93C-0003939e0af6</id>
<entry>
<title>M 3.2, Mona Passage</title>
<link href="http://example.org/2005/09/09/atom01"/>
<id>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</id>
<updated>2005-08-17T07:02:32Z</updated>
<summary>We just had a big one.</summary>
<georss:point>45.256 -71.92</georss:point>
</entry>
</feed>