The SEDRIS Data Representation Model
APPENDIX A - Classes
Quadrant Related Features

Class Name: Quadrant Related Features

Superclass - <Aggregate Feature>

Subclasses

This DRM class is concrete and has no subclasses.

Definition

An instance of this DRM class specifies an aggregation of <Feature Hierarchy> components in which each <Feature Hierarchy> component represents a branch of a quadrant. The quadrant represented by a branch is specified by the <Quadrant Data> link object associated with that branch. The bounding region that the <Feature Hierarchy> components occupy is defined by the <Spatial Extent> component of the <Quadrant Related Features> instance.

Primary Page in DRM Diagram:

Secondary Pages in DRM Diagram:

This class appears on only one page of the DRM class diagram.

Example

  1. Consider a region of terrain that is organized into quadrants, where the SE_QUADRANT_RIGHT_FRONT quadrant consists of ocean, and the other three quadrants consist of the terrain bordering the ocean. The ocean quadrant is not represented in the producer's system. The region is represented in the DRM by a <Quadrant Related Features> instance with three <Union Of Features> components as depicted in Figure 6.49. Since the remaining quadrant had no <Feature Representation> instances, it is not represented.

    Quadrant Related Features, Example 1

    Figure 49 — <DRM Quadrant Related Features> ocean example

  2. Consider a <Quadrant Related Features> instance linked to a <Union Of Features> instance representing its SE_QUADRANT_RIGHT_FRONT quadrant, using a <Quadrant Data> link object. The <Quadrant Data> link object's quadrant value is SE_QUADRANT_RIGHT_FRONT as depicted in Figure 6.50

    Quadrant Related Features, Example 2

    Figure 50 — <DRM Quadrant Related Features> example

FAQs

If a <Quadrant Related Features> instance has less than four components, why is the data being represented using a <Quadrant Related Features> instance at all?

A <Quadrant Related Features> instance is used when the environmental data to be represented logically lends itself to a quadrant related organization. However, since a given quadrant within such an organization might not contain <Primitive Feature> instances, a <Quadrant Related Features> instance can have fewer than four components.

Where is the <Spatial Extent> component?

A <Quadrant Related Features> instance automatically has a <Spatial Extent> component, because it is a <Feature Hierarchy> instance.

Constraints

Associated to (one-way) (inherited)

Associated by (one-way) (inherited)

Composed of (two-way) (inherited)

Composed of (two-way)

Composed of (two-way metadata) (inherited)

Component of (two-way) (inherited)

Inherited Field Elements

SE_Boolean unique_descendants; 9
SE_Boolean strict_organizing_principle; 10

Notes

Associated to Notes


Feature_Representation

An association between two <Feature Representation> instances indicates that the environmental object(s) that they represent have the semantic relationship indicated by the <Base Association Data> link object on the association relationship.


Geometry_Hierarchy

An association between a <Geometry Hierarchy> instance and a <Feature Representation> instance indicates that the environmental object(s) that they represent have the semantic relationship indicated by the <Base Association Data> link object on the association relationship.


Property_Grid

An association between a <Property Grid> instance and a <Feature Representation> instance indicates that the environmental object(s) represented by the <Feature Representation> instance and the <Property Grid> instance (or some specific cell data within that <Property Grid> instance) have the semantic relationship indicated by the <Base Association Data> link object on the association relationship. Each associated <Property Grid> instance indicates whether the entire <Property Grid> instance or only some specific cell data within it is participating in the relationship in question.

Associated from Notes


Feature_Representation

An association between two <Feature Representation> instances indicates that the environmental object(s) that they represent have the semantic relationship indicated by the <Base Association Data> link object on the association relationship.


Geometry_Hierarchy

An association between a <Geometry Hierarchy> instance and a <Feature Representation> instance indicates that the environmental object(s) that they represent have the semantic relationship indicated by the <Base Association Data> link object on the association relationship.


Property_Grid

An association between a <Property Grid> instance and a <Feature Representation> instance indicates that the environmental object(s) represented by the <Feature Representation> instance and the <Property Grid> instance (or some specific cell data within that <Property Grid> instance) have the semantic relationship indicated by the <Base Association Data> link object on the association relationship. Each associated <Property Grid> instance indicates whether the entire <Property Grid> instance or only some specific cell data within it is participating in the relationship in question.

Composed of Notes


Image_Mapping_Function

The <Image Mapping Function> components support texture mapping information for geometry that is to be derived from the <Aggregate Feature> instance by the consumer. These <Image Mapping Function> instances shall use <Image Anchor> components to specify the mapping.


Presentation_Domain

A <Presentation Domain> component is needed for <Aggregate Feature> instances that are significant only for a particular domain, such as radar.

Fields Notes

unique_descendants

If the value of the unique_descendants field is SE_TRUE, each descendant shall be unique in the sense that it shall appear in only one branch of this aggregation. Each descendant is a <Feature Representation> instance within the component tree rooted at the <Aggregate Feature> instance. If unique_descendants is SE_FALSE, at least one <Feature Representation> instance appears in more than one branch of the aggregation.

strict_organizing_principle

If the value of the strict_organizing_principle field is SE_TRUE, each branch of this aggregation strictly complies with the organizing principle for its particular subclass. If this value is SE_FALSE, at least one branch does not strictly comply with the given organizing principle. See the organizing principle constraint for each specific subclass for details.


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Last updated: July 26, 2006 Copyright © 2006 SEDRIS