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The SEDRIS Data Representation Model
APPENDIX A - Classes Areal Feature |
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An instance of this DRM class specifies a <Primitive Feature> instance that encloses a bounded region, such as a forest or a built-up area.
Consider an <Areal Feature> instance representing a lake. It has a <Feature Face> instance, which defines its size, shape, and topological relationships; a <Classification Data> component that identifies it as a lake; <Property Value> components that describe its characteristics, such as bottom composition; and a <Label> component that identifies it as "Duck Lake".
No. Although in VPF, for example, the mere presence of Faces implies Level 3 topology, this is not the case in the DRM. <Areal Feature> instances may exist at any level of topology.
An <Areal Feature> instance can consist of multiple <Feature Face> instances. There is no requirement that the <Feature Face> instances be connected to one another.
For example, a forest that has a stream and a road passing through it commonly is represented as a single <Areal Feature> instance, but might require multiple <Feature Face> instances.
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