The SEDRIS Data Representation Model
APPENDIX A - Classes
Property Set Index

Class Name: Property Set Index

Superclass - <SEDRIS Abstract Base>

Subclasses

This DRM class is concrete and has no subclasses.

Definition

An instance of this DRM class specifies the means of referencing the contents of a <Property Set> instance that is contained in a <Property Set Table> instance.

A <Property Set Index> instance specifies an index into the primary <Property Set Table> component of the <Property Set Table Group> instance to which it is associated. The <Property Set Table Group> instance specifies which of its <Property Set Table> components is being used, while the <Property Set Index> instance specifies which <Property Set> component within that primary <Property Set Table> instance is being referenced.

Primary Page in DRM Diagram:

Secondary Pages in DRM Diagram:

Example

  1. Consider a <Property Set Table Group> instance, such that the kth <Property Set> component of its primary <Property Set Table> component consists of <Colour> components and <Image Mapping Function> components for sandy ground under normal, OTW viewing conditions.

    A terrain <Polygon> instance that references this set does so by having a <Property Set Index> component that is associated to the <Property Set Table Group> instance and the index value of which is set to k.

FAQs

Does a <Property Set Index> instance specify a one-based index?

Yes.

Consider a DRM object, the properties which are specified by a <Property Set Index>. How can a consumer get access to the actual property objects being referred to?

A consumer can access the actual property objects contained within the <Property Set Table>, as though they had been directly attached to the object. See SE_InitializeComponentIterator()'s directly_attach_table_components parameter, and SE_GetComponent()'s directly_attach_table_components parameter.

Constraints

Associated to (one-way)

Composed of (two-way)

Component of (two-way)

Inherited Field Elements

This class has no inherited field elements.

Field Elements

SE_Integer_Positive index; 2

Notes

Composed of Notes


Property_Set_Index_Control_Link

If a <Property Set Index> instance is subject to dynamic control (that is, if its index value can vary), it has a <Property Set Index Control Link> component to express that control mechanism.

Fields Notes

index

The index field specifies which <Property Set> instance is being referenced within the primary <Property Set Table> component of the associated <Property Set Table Group> instance. For a <Property Set Index> instance with a <Property Set Index Control Link> component X, the value of the index field is obtained from X.


Prev: Property Set. Next: Property Set Index Control Link. Up:Index.

Last updated: July 26, 2006 Copyright © 2006 SEDRIS