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includes dual along referents located elsewhere in the same document. Either the reference or the contained element shall be given, but neither both nor none.
9.5 Linear Referencing Offset
9.5.1 Target namespace
All schema components specified in this subclause are in the target namespace: http:www.opengis.netgml3.3lro
9.5.2 Introduction
Linear Referencing Offset includes the specification of linearly referenced locations which can have lateral and vertical offsets in their distance expressions.
9.5.3 LRMWithOffset
complexType name=LRMWithOffsetType complexContent
extension base=gmllr:LinearReferencingMethodType sequence
element name=offsetUnits type=gml:UomIdentifier element name=positiveLateralOffsetDirection
type=gmllro:LateralOffsetDirectionType default=right minOccurs=0
element name=positiveVerticalOffsetDirection type=gmllro:VerticalOffsetDirectionType default=up
minOccurs=0 sequence
extension complexContent
complexType element name=LRMWithOffset type=gmllro:LRMWithOffsetType
substitutionGroup=gmllr:LinearReferencingMethod gmllro:LRMWithOffset implements ISO 19148 LRO_LRMWithOffset see ISODIS 19148, 6.4.2.
A gmllro:LRMWithOffset specifies the manner in which measurements are made along and optionally laterally offset from a linear element.
The element gmllro:offsetUnits specifies the offset units of measure used by the Linear Referencing Method as a gml:UomIdentifier. It is mandatory for Linear Referencing Methods that allow offsets.. This
applies to measurements made laterally, vertically or along a vector from the linear element to an offset location.
The optional element gmllro:positiveLateralOffsetDirection gives the
gmllro:LateralOffsetDirectionType value used as the positive direction for the Linear Referencing Method for lateral measures perpendicular to the linear element. It is only applicable to Linear Referencing
Methods that allow offsets. Allowable values are specified by the gmllro:LateralOffsetDirectionType codelist. The default value is right.
The optional element gmllro:positiveVerticalOffsetDirection
gives the gmllro:VerticalOffsetDirectionType value used as the positive direction for the Linear Referencing
Method for vertical measures perpendicular to the linear element. It is only applicable to Linear Referencing
46 Copyright © 2012 Open Geospatial Consortium
Methods that allow offsets. Allowable values are specified by the gmllro:VerticalOffsetDirectionType codelist. The default value is up.
9.5.4 LRMWithOffsetPropertyType