Class

• <DRM Feature Face Ring>

Superclass

• <DRM SEDRIS Abstract Base>

Subclass

• None.

Definition

An instance of this DRM class specifies the one-directional topological relationship from a <DRM Feature Face> instance to the ordered collection of one or more <DRM Feature Edge> instances that define one of its boundaries (outer or inner).

Class diagram

Figure 6.87 — DRM_Feature_Face_Ring

Constraints

• Face ring edge consistency
• Publishable object

Example(s)

• Consider a <DRM Areal Feature> instance L representing an environmental object classified as ECC_LAKE. The topology of L is represented by a regular <DRM Feature Face> instance, the outer boundary of which is defined by two <DRM Feature Edge> instances, one defining the north shore of the lake, the other defining the south shore.

  To indicate that these two <DRM Feature Edge> instances define the outer boundary of the lake, each is a component of an external <DRM Feature Face Ring> instance through a <DRM Edge Direction> link object that indicates its orientation with respect to the <DRM Feature Face Ring> instance. The <DRM Feature Face Ring> instance is in turn a component of the <DRM Feature Face> instance specifying the topology of L. These relationships are depicted in Figure 6.88:

  

  Figure 6.88 — <DRM Feature Face Ring> example