Abstract head of the substitution group for DIGGS standalone surface geometries(diggs:PlanarSurface, diggs:MultiPlanarSurface, diggs:TriangulatedSurface,diggs:CompositeSurface). It excludes diggs:Shell, which is one boundary component ofa solid rather than a surface in its own right. A property that wants any realsurface, not the boundary piece of a solid, should reference diggs:AbstractSurfacerather than gml:AbstractSurface.
Database handle for the object. It is of XML type ID, so is constrained to beunique in the XML document within which it occurs. An external identifier for the object inthe form of a URI may be constructed using standard XML and XPointer methods. This is doneby concatenating the URI for the document, a fragment separator, and the value of the idattribute.
<element abstract="true" name="AbstractSurface" substitutionGroup="diggs:AbstractGeometricPrimitive" type="diggs:AbstractSurfaceType"><annotation><documentation>Abstract head of the substitution group for DIGGS standalone surface geometries (diggs:PlanarSurface, diggs:MultiPlanarSurface, diggs:TriangulatedSurface, diggs:CompositeSurface). It excludes diggs:Shell, which is one boundary component of a solid rather than a surface in its own right. A property that wants any real surface, not the boundary piece of a solid, should reference diggs:AbstractSurface rather than gml:AbstractSurface.</documentation></annotation></element>