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GeneralGridAxis generalGridAxis
generalGridAxis GeneralGridAxis
offsetVector0.667 -0.667offsetVector coefficients
0 0 2 3 3 3 4 4 5 6
7 7 8 8 9 9 8.5 9.5 9 10
coefficients gridAxesSpannedx ygridAxesSpanned
sequenceRule axisOrder=+1 +2LinearsequenceRule GeneralGridAxis
generalGridAxis ReferenceableGridByVectors
Figure 9 — ReferenceableGridByVectors – curvilinear grid with coefficient arrays
10.6 ReferenceableGridByTransformation
element name=ReferenceableGridByTransformation type=gmlrgrid:ReferenceableGridByTransformationType
substitutionGroup=gmlrgrid:AbstractReferenceableGrid complexType name=ReferenceableGridByTransformationType
complexContent extension base=gmlrgrid:AbstractReferenceableGridType
choice element name=transformation type=gml:TransformationPropertyType
70 Copyright © 2012 Open Geospatial Consortium
element name=concatenatedOperation type=gml:ConcatenatedOperationPropertyType
choice extension
complexContent complexType
ReferenceableGridByTransformation encodes one type of CV_ReferenceableGrid as defined in ISO 19123, using a gml:Transformation or gml:ConcatenatedOperation to specify the relationship between positions in the
grid and corresponding positions in another CRS.
The choice in ReferenceableGridByTransformation encodes an association to a coordinate Transformation or Concatenated Operation that georeferences this ReferenceableGrid. This Transformation or Concatenated
Operation shall reference the grid CRS for this gml:AbstractReferenceableGrid, as either its sourceCRS or targetCRS. If a grid is referenced to more than one other CRS, or is referenced to the same other CRS by
multiple Transformation versions, different grids and different coverages shall be used.
10.7 gridCRS
element name=gridCRS type=gmlrgrid:GridCRSPropertyType complexType name=GridCRSPropertyType
sequence element ref=gml:AbstractCRS
sequence complexType
A grid coordinate reference system for positions in a ReferenceableGrid that uses a defined coordinate system congruent with the coordinate system described by the GridEnvelope and axisLabels of gml:GridType.
That is, this defined coordinate system shall have the same grid axis positions and origin as the GridEnvelope, with the same axisLabels, but need not define the same or any limits on the grid size. In addition to this
defined coordinate system, a gridCRS shall have a defined datum, whose origin may be a specific grid point in a specific quadrilateral grid coverage that uses this gridCRS.
The gridCRS is a composition association to the definition of the CRS for this AbstractReferenceableGrid. This CRS may be a DerivedCRS, EngineeringCRS, ImageCRS, or CompoundCRS.
NOTE The proposed OGC Best Practices Paper 09-085r1 recommends that this gridCRS always be a
DerivedCRS.
10.8 Coverages using ReferencableGrid
