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

Class Name: State Related Features

Superclass - <Aggregate Feature>

Subclasses

This DRM class is concrete and has no subclasses.

Definition

An instance of this DRM class specifies a state related organization of <Feature Hierarchy> components where each <Feature Hierarchy> component represents a separate discrete state from a possibly continuous state value. Each discrete state corresponds to a branch of the <State Related Features> instance and is identified by the <State Data> link object for that branch. The state value itself is specified by the state_tag of the <State 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 <Feature Model> instance representing a road in various states of damage due to flooding. The topological connections of the road differ in each damage state due to bridges being washed away and various road segments being blocked due to obstructions such as fallen trees.

    Consequently, the <Feature Model> instance has a <State Related Features> component with state_tag = EAC_GENERAL_DAMAGE_FRACTION and active_state_value = 0.0 % (that is, initially the road is undamaged, before flooding takes place). This is depicted in Figure 6.66.

    State Related Features, Example 1

    Figure 66 — <DRM State Related Features> damage example

    The <State Data> link object for each branch indicates the range of percent damage for which that branch describes the feature topology of the road.

    If the active_state_value is controlled dynamically, the mismatch_behaviour field of the <State Control Link> instance specifies what happens if the active_state_value is greater than 50%.

FAQs

Are <State Related Features> instances the only way to represent multi-state environmental objects in the DRM?

No. <Control Link> instances can be used to provide a fine level of control over state by changing fields instead of representing states as different <Feature Representation> instances.

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

Field Elements

EDCS_Attribute_Code state_tag; 11
EDCS_Attribute_Value active_state_value; 12

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.

state_tag

The state_tag field specifies the state by which the <Feature Hierarchy> components are being differentiated and shall specify an EAC that qualifies as state applicable.

active_state_value

The active_state_value field specifies the default state. If the <State Related Features> instance has a <State Control Link> component, the value of the active_state_value field is obtained from that <State Control Link> instance.


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Last updated: July 26, 2006 Copyright © 2006 SEDRIS