geometryComplexes.xsd See ISO/DIS 19136 12.2. Geometric complexes (i.e. instances of gml:GeometricComplexType) are closed collections of geometric primitives, i.e. they will contain their boundaries. A geometric complex (gml:GeometricComplex) is defined by ISO 19107:2003, 6.6.1 as "a set of primitive geometric objects (in a common coordinate system) whose interiors are disjoint. Further, if a primitive is in a geometric complex, then there exists a set of primitives in that complex whose point-wise union is the boundary of this first primitive." A geometric composite (gml:CompositeCurve, gml:CompositeSurface and gml:CompositeSolid) represents a geometric complex with an underlying core geometry that is isomorphic to a primitive, i.e. it can be viewed as a primitive and as a complex. See ISO 19107:2003, 6.1 and 6.6.3 for more details on the nature of composite geometries. Geometric complexes and composites are intended to be used in application schemas where the sharing of geometry is important. GML is an OGC Standard. Copyright (c) 2007,2010 Open Geospatial Consortium. To obtain additional rights of use, visit http://www.opengeospatial.org/legal/ . A property that has a geometric complex as its value domain may either be an appropriate geometry element encapsulated in an element of this type or an XLink reference to a remote geometry element (where remote includes geometry elements located elsewhere in the same document). Either the reference or the contained element shall be given, but neither both nor none. A gml:CompositeCurve is represented by a sequence of (orientable) curves such that each curve in the sequence terminates at the start point of the subsequent curve in the list. curveMember references or contains inline one curve in the composite curve. The curves are contiguous, the collection of curves is ordered. Therefore, if provided, the aggregationType attribute shall have the value "sequence". A gml:CompositeSurface is represented by a set of orientable surfaces. It is geometry type with all the geometric properties of a (primitive) surface. Essentially, a composite surface is a collection of surfaces that join in pairs on common boundary curves and which, when considered as a whole, form a single surface. surfaceMember references or contains inline one surface in the composite surface. The surfaces are contiguous. gml:CompositeSolid implements ISO 19107 GM_CompositeSolid (see ISO 19107:2003, 6.6.7) as specified in D.2.3.6. A gml:CompositeSolid is represented by a set of orientable surfaces. It is a geometry type with all the geometric properties of a (primitive) solid. Essentially, a composite solid is a collection of solids that join in pairs on common boundary surfaces and which, when considered as a whole, form a single solid. solidMember references or contains one solid in the composite solid. The solids are contiguous.