Abstract Class Name: Feature Topology

Superclass - <SEDRIS Abstract Base>

Subclasses

• <Feature Edge>
• <Feature Face>
• <Feature Node>

Definition

The objects that define both the geometric (i.e., location, shape) and topological (i.e., adjacency) aspects of <Features>, including <Feature Nodes>, <Feature Edges>, and <Feature Faces>. A topological surface consists of a collection of <Feature Topology> instances related to one another through a variety of topological relationships.

Primary Page in DRM Diagram:

• 12

Secondary Pages in DRM Diagram:

• 11

Example

1. In a collection of <Feature> instances representing a transportation network, the <Feature Face> instances represent built-up areas, airfields, railroad yards, and parking lots, the <Feature Edge> instances represent their boundaries as well as roads, railroads, and runways, and the <Feature Node> instances represent road intersections and railroad crossings.

FAQs

Why is <Feature Topology> defined separately from <Geometry Topology>?

<Feature Topology> includes both the geometric and the topological aspects of <Features>, while <Geometry Topology> includes only the topological aspects of <Geometry>, which are completely optional.

Constraints

• <<No Attribute Conflicts>>

Composed of (two-way)

• zero or one <Feature ID> instance
• zero or more <Property Value> instances

Component of (two-way)

• zero or more <Union Of Feature Topology> instances

Inherited Field Elements