Class Name: Feature Node

Superclass - <Feature Topology>

Subclasses

Definition

An instance of this DRM class is a zero-dimensional <Feature Topology> instance used to represent the location of a <Point Feature> and / or the endpoints of one or more <Feature Edge> instances.

Primary Page in DRM Diagram:

• 12

Secondary Pages in DRM Diagram:

• 8

Example

1. The location of a small building might be represented by a single <Feature Node>.

2. The intersection of two roads would be represented by a <Feature Node>.

FAQs

When are <Feature Node> instances required?

<Feature Node> instances are required whenever either <Point Feature> or <Feature Edge> instances are present, regardless of the feature topology level.

Are there any geometric constraints on the <Location> that is associated with a <Feature Node>?

Yes. At all feature topology levels greater than zero, different <Feature Node> instances cannot share the same <Location>.

Constraints

• <<No Attribute Conflicts>>
• <<Connected Edge Restrictions>>
• <<Contained Node Restrictions>>
• <<Non Crossing Associations>>

Associated by (one-way)

• zero or more <Feature Edge> instances (notes)

Associated with (two-way)

• zero or one <Feature Face> instance (notes)
• zero or more <Feature Node> instances
• zero or more <Point Feature> instances

Composed of (two-way)(inherited)

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

Composed of (two-way)

• zero or more {ordered} <Connected Feature Edge> instances
• one <Location> instance
• zero or more <Same As Feature Node> instances

Component of (two-way)(inherited)

• zero or more <Union Of Feature Topology> instances

Inherited Field Elements

Notes

Associated with Notes

Feature_Edge

 The other half of this relationship is supplied by the
 <Connected Feature Edge> component of the given
 <Feature Node> instance.

Feature_Face

 This identifies the <Feature Face> that contains the given
 <Feature Node> instance, if one exists.