Ring, RingType, curveMember OrientableSurfaceType, OrientableSurface, baseSurface

80 Copyright © 2007 Open Geospatial Consortium, Inc. All Rights Reserved. A ring is used to represent a single connected component of a surface boundary as specified in ISO 19107:2003, 6.3.6. Every gml:curveMember references or contains one curve, i.e. any element which is substitutable for gml:AbstractCurve. In the context of a ring, the curves describe the boundary of the surface. The sequence of curves shall be contiguous and connected in a cycle. If provided, the aggregationType attribute shall have the value ―sequence‖. NOTE This definition allows for a nested structure, i.e. a gml:curveMember may be a gml:CompositeCurve which in turn may be constructed from other gml:CompositeCurves as a curve members.

10.5.11.2 RingPropertyType

complexType name=RingPropertyType sequence element ref=gml:Ring sequence complexType A property with the content model of gml:RingPropertyType encapsulates a ring to represent a component of a surface boundary.

10.5.11.3 PolyhedralSurface

element name=PolyhedralSurface type=gml:SurfaceType substitutionGroup=gml:Surface gml:PolyhedralSurface implements ISO 19107 GM_PolyhedralSurface see D.2.3.4 and ISO 19107:2003, 6.4.35. A polyhedral surface is a surface composed of polygon patches connected along their common boundary curves. gml:patches encapsulates the polygon patches of the polyhedral surface. All patches shall be polygon patches.

10.5.11.4 TriangulatedSurface

element name=TriangulatedSurface type=gml:SurfaceType substitutionGroup=gml:Surface gml:TriangultedSurface implements ISO 19107 GM_TriangulatedSurface see D.2.3.4 and ISO 19107:2003, 6.4.37. A triangulated surface is a polyhedral surface that is composed only of triangles. There is no restriction on how the triangulation is derived. gml:patches encapsulates the triangles of the triangulated surface. All patches shall be triangle patches.

10.5.11.5 TinType, Tin

complexType name=TinType complexContent extension base=gml:TriangulatedSurfaceType sequence element name=stopLines type=gml:LineStringSegmentArrayPropertyType minOccurs=0 maxOccurs=unbounded element name=breakLines type=gml:LineStringSegmentArrayPropertyType minOccurs=0 Copyright © 2007 Open Geospatial Consortium, Inc. All Rights Reserved. 81 maxOccurs=unbounded element name=maxLength type=gml:LengthType element name=controlPoint complexType choice element ref=gml:posList group ref=gml:geometricPositionGroup minOccurs=3 maxOccurs=unbounded choice complexType element sequence extension complexContent complexType element name=Tin type=gml:TinType substitutionGroup=gml:TriangulatedSurface gml:Tin implements ISO 19107 GM_Tin see D.2.3.4 and ISO 19107:2003, 6.4.39. A tin is a triangulated surface that uses the Delauny algorithm or a similar algorithm complemented with consideration of stoplines gml:stopLines, breaklines gml:breakLines, and maximum length of triangle sides gml:maxLength. gml:controlPoint shall contain a set of the positions three or more used as posts for this TIN corners of the triangles in the TIN. See ISO 19107:2003, 6.4.39 for details.

10.5.11.6 LineStringSegmentArrayPropertyType

complexType name=LineStringSegmentArrayPropertyType sequence minOccurs=0 maxOccurs=unbounded element ref=gml:LineStringSegment sequence complexType gml:LineStringSegmentArrayPropertyType provides a container for line strings. 10.5.12 Surface patches 10.5.12.1 AbstractSurfacePatchType, gml : AbstractSurfacePatch complexType name=AbstractSurfacePatchType abstract=true element name=AbstractSurfacePatch type=gml:AbstractSurfacePatchType abstract=true A surface patch defines a homogenous portion of a surface. gml:AbstractSurfacePatch implements ISO 19107 GM_SurfacePatch see D.2.3.4 and ISO 19107:2003, 6.4.34. The gml:AbstractSurfacePatch element is the abstract head of the substitution group for all surface patch elements describing a continuous portion of a surface. All surface patches shall have an attribute interpolation declared in the types derived from gml:AbstractSurfacePatchType specifying the interpolation mechanism used for the patch using gml:SurfaceInterpolationType see 10.5.12.3.