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

Class Name: Time Related Features

Superclass - <Aggregate Feature>

Subclasses

This DRM class is concrete and has no subclasses.

Definition

An instance of this DRM class is an aggregation of <Feature Hierarchy> instances, in which each branch is a representation of the same environmental entity at a different point in time, as indicated by the corresponding <Time Constraints Data> 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. A lake that varies in size significantly with the seasons could be represented as a <Time Related Features> instance, with two (or more) component <Union Of Features> instances, each containing a single <Areal Feature> representing the lake.

FAQs

No FAQs supplied.

Constraints

Associated by (one-way)(inherited)

Associated with (two-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; (notes)
SE_Boolean strict_organizing_principle; (notes)

Field Elements

SE_Time_Data_Type time_data_type;

Notes

Associated with Notes


Feature

 An association between two <Feature> instances indicates
 that they are alternate representations of the same
 environmental object.

Geometry_Hierarchy

 An association between a <Geometry Hierarchy> instance and a
 <Feature> instance indicates that the <Geometry Hierarchy>
 and the <Feature> are alternate representations of the same
 environmental object.

Property_Grid

 An association between a <Property Grid> instance and a
 <Feature> indicates that the <Feature> and the <Property Grid>
 (or some specific cell data within that <Property Grid>) are
 alternate representations of the same environmental object.
 Each associated <Property Grid> will indicate which is the case.

Composed of Notes


Image_Mapping_Function

 This relationship exists to support "attributes for derived objects."
 That is, these components are used only to specify texture mapping
 information for geometry that is to be derived from the
 <Aggregate Feature> by the consumer. These <Image Mapping Functions>
 shall use <Image Anchor> components to specify the mapping.

Presentation_Domain

 This is needed because in many cases, an <Aggregate Feature> may be
 significant only for a particular domain, e.g. radar.

Fields Notes


unique_descendants

 If this value is SE_TRUE, each 'descendant' of this aggregation -
 that is, each <Feature> object that exists in the component tree
 rooted at the given <Aggregate Feature> - shall be unique, in the
 sense that it shall appear in only one 'branch' of this aggregation.
 If unique_descendants is SE_FALSE, at least one <Feature> object
 appears in more than one 'branch' of the aggregation.

strict_organizing_principle

 If this value 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: October 1, 2002 Copyright © 2002 SEDRIS™