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Specification]. As a convention, the vertices of the Polygon especially the vertices of the exterior LinearRing should
be specified in counter‐clockwise direction to correctly define the VisualAsset’s front face. See Orienting VisualAssets for details.
Requirement
http:www.opengis.netspecarml2.0reqmodelGMLGeometriesLinearRingorder A LinearRing’s coordinate tuples shall be specified in counter‐clockwise order.
XML Example:
gml:Polygon gml:id=myPolygon gml:exterior
gml:LinearRing gml:posList
47.48 13.14 48.49 14.15 48.49 14.13 47.48 13.14 gml:posList
gml:LinearRing gml:exterior
gml:interior gml:LinearRing
gml:posList 48.00 14.00 48.01 14.01 48.01 13.99 48.00 14.00
gml:posList gml:LinearRing
gml:interior gml:interior
gml:LinearRing ...
gml:LinearRing gml:interior
gml:Polygon
7.4.1.2 Trackable and Tracker
7.4.1.2.1 class Tracker
The src and uri properties are specified in xlink:href attributes, see the XSD below.
XSD:
xsd:complexType name=TrackerType xsd:complexContent
xsd:extension base=ARElementType xsd:sequence
xsd:element name=uri maxOccurs=1 minOccurs=1 xsd:complexType
xsd:attribute ref=xlink:href use=required xsd:complexType
xsd:element xsd:element name=src maxOccurs=1 minOccurs=0
xsd:complexType
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xsd:attribute ref=xlink:href use=required xsd:complexType
xsd:element xsd:sequence
xsd:extension xsd:complexContent
xsd:complexType xsd:element name=Tracker type=TrackerType
substitutionGroup=ARElement
XML Example:
-- a generic image Tracker -- Tracker id=myGenericImageTracker
uri xlink:href=http:www.opengis.netarmltrackergenericImageTracker Tracker
-- a generic image Tracker operating on a set of image targets supplied via a zip file --
Tracker id=myGenericImageTrackerWithZip uri xlink:href=http:www.opengis.netarmltrackergenericImageTracker
src xlink:href=http:www.myserver.commyTargetsmyTargets.zip Tracker
-- a custom Tracker -- Tracker id=myCustomTracker
uri xlink:href=http:www.myServer.commyTracker src xlink:href=http:www.myServer.commyTrackablesbinary.file
Tracker
7.4.1.2.2 class Trackable
XSD:
xsd:complexType name=TrackableType xsd:complexContent
xsd:extension base=ARAnchorType xsd:sequence
xsd:element name=config maxOccurs=unbounded minOccurs=1 xsd:complexType
xsd:sequence xsd:element name=tracker maxOccurs=1 minOccurs=1
xsd:complexType xsd:attribute ref=xlink:href use=required
xsd:complexType xsd:element
xsd:element name=src type=xsd:string maxOccurs=1 minOccurs=1
xsd:sequence xsd:attribute name=order type=xsd:int use=optional
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xsd:complexType xsd:element
xsd:element name=size type=xsd:double maxOccurs=1 minOccurs=0
xsd:sequence xsd:extension
xsd:complexContent xsd:complexType
xsd:element name=Trackable type=TrackableType substitutionGroup=ARAnchor
XML Example:
-- using the trackers specified above -- -- a png image tracked with the generic image tracker --
Trackable id=myBirdTrackable config
tracker xlink:href=myGenericImageTracker srchttp:www.myserver.commyTrackablesbird.pngsrc
config size0.2size -- in real word dimensions, the bird image is 20 cm
wide -- Trackable
-- a jpg image tracked with the generic image tracker operating on a zip file--
Trackable id=myBirdTrackableInZip config
tracker xlink:href=myGenericImageTrackerWithZip srcimagesbird.pngsrc
config size0.2size
Trackable -- a jpg image tracked with the generic image tracker operating on a zip
file-- Trackable id=myCustomBirdTrackable
config tracker xlink:href=myCustomTracker
srcbirdsrc -- the custom tracker is supposed to understand the ID bird in the Trackers binary container --
config size0.2size
Trackable —a Trackable that can be tracked in two different ways, preferably with a
custom implementation that takes a binary file, and if this configuration is not available, a generic imagetracker should be used--
Trackable id=myTrackable config order=1
tracker xlink:href=myCustomSuperSpeedyTracker srchttp:www.myserver.commyTrackablesbird.datsrc
config
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—fallback -- config order=2
tracker xlink:href=myGenericImageTracker srchttp:www.myserver.commyTrackablesbird.pngsrc
config size0.2size
Trackable
7.4.1.3 class RelativeTo Requirement