The SEDRIS Data Representation Model
APPENDIX A - Classes
Reference Vector Control Link

Class Name: Reference Vector Control Link

Superclass - <Control Link>

Subclasses

This DRM class is concrete and has no subclasses.

Definition

An instance of this DRM class is a specialized <Control Link> instance providing the connection between an ordered aggregation of <Expression> instances and the target field values of one or more <Reference Vector> instances.

Primary Page in DRM Diagram:

Secondary Pages in DRM Diagram:

Example

  1. For the <Reference Vector> component of a <Polygon> instance the <Reference Vector> instance specifies its normal, so the <Expression> instances compute the three fields of the normal of a <Polygon> instance.

  2. A <Model> instance representing a lighthouse has a <Geometry Model> component with a <Union Of Geometry Hierarchy> component, to which is attached a <Spot Light> instance representing the lighthouse's light. The <Spot Light> instance has a <Lobe Data> component describing the shape of the light cone, in which a <Reference Vector> instance specifies the light direction. The SE_REFVEC_LIGHT_DIRECTION <Reference Vector> instance has a <Reference Vector Control Link> component to change the direction vector of the light so that the lighthouse light sweeps over an area rather than holding stationary.

FAQs

No FAQs supplied.

Constraints

Composed of (two-way) (inherited)

Component of (two-way)

Inherited Field Elements

SE_String description; 1

Field Elements

SE_Integer_Unsigned v0_expression_index; 2
SE_Integer_Unsigned v1_expression_index; 3
SE_Integer_Unsigned v2_expression_index; 4

Notes

Fields Notes

description

The description field specifies a text description of the purpose of the <Control Link> instance.

v0_expression_index

The v0_expression_index field specifies which <Expression> component, if any, controls the value of the first array element of the unit_vector field of the affected <Reference Vector> instances. If the value is zero, the value of the first array element of the unit_vector field of those instances is not controlled; otherwise, the value is a one-based index into the ordered aggregation of <Expression> instances.

v1_expression_index

The v1_expression_index field specifies which <Expression> component, if any, controls the value of the second array element of the unit_vector field of the affected <Reference Vector> instances. If the value is zero, the value of the second array element of the unit_vector field of those instances is not controlled; otherwise, the value is a one-based index into the ordered aggregation of <Expression> instances.

v2_expression_index

The v2_expression_index field specifies which <Expression> component, if any, controls the value of the third array element of the unit_vector field of the affected <Reference Vector> instances. If the value is zero, the value of the third array element of the unit_vector field of those instances is not controlled; otherwise, the value is a one-based index into the ordered aggregation of <Expression> instances.


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Last updated: July 26, 2006 Copyright © 2006 SEDRIS