feature.xsd See ISO/DIS 19136 Clause 9. A GML feature is a (representation of a) identifiable real-world object in a selected domain of discourse. The feature schema provides a framework for the creation of GML features and feature collections. The basic feature model is given by the gml:AbstractFeatureType. The content model for gml:AbstractFeatureType adds two specific properties suitable for geographic features to the content model defined in gml:AbstractGMLType. The value of the gml:boundedBy property describes an envelope that encloses the entire feature instance, and is primarily useful for supporting rapid searching for features that occur in a particular location. The value of the gml:location property describes the extent, position or relative location of the feature. This abstract element serves as the head of a substitution group which may contain any elements whose content model is derived from gml:AbstractFeatureType. This may be used as a variable in the construction of content models. gml:AbstractFeature may be thought of as “anything that is a GML feature” and may be used to define variables or templates in which the value of a GML property is “any feature”. This occurs in particular in a GML feature collection where the feature member properties contain one or multiple copies of gml:AbstractFeature respectively. This property describes the minimum bounding box or rectangle that encloses the entire feature. gml:EnvelopeWithTimePeriod is provided for envelopes that include a temporal extent. It adds two time position properties, gml:beginPosition and gml:endPosition, which describe the extent of a time-envelope. Since gml:EnvelopeWithTimePeriod is assigned to the substitution group headed by gml:Envelope, it may be used whenever gml:Envelope is valid. deprecated deprecated deprecated deprecated The gml:locationName property element is a convenience property where the text value describes the location of the feature. If the location names are selected from a controlled list, then the list shall be identified in the codeSpace attribute. The gml:locationReference property element is a convenience property where the text value referenced by the xlink:href attribute describes the location of the feature. deprecated deprecated deprecated deprecated deprecated deprecated deprecated deprecated To create a collection of GML features, a property type shall be derived by extension from gml:AbstractFeatureMemberType. By default, this abstract property type does not imply any ownership of the features in the collection. The owns attribute of gml:OwnershipAttributeGroup may be used on a property element instance to assert ownership of a feature in the collection. A collection shall not own a feature already owned by another object. deprecated deprecated deprecated deprecated