Class Name: Sound Instance Control Link

Superclass - <Control Link>

Subclasses

Definition

An instance of this DRM class is a specialized <Control Link> used to provide the connection between an ordered aggregation of <Expression> instances and the target fields of a <Sound Instance>.

The active_sound_value_expr_index field is a 1-based index into the ordered aggregation of <Expression> instances, and is used to select the specific <Expression> that defines the <Sound Instance>'s active_sound_value field.

Primary Page in DRM Diagram:

• 17

Secondary Pages in DRM Diagram:

• 21

Example

1. A <Model> of a lighthouse has a <Geometry Model> with a <Union Of Geometry Hierarchy>, to which is attached a <Sound Instance> representing the foghorn. The <Sound Instance> has a <Sound Instance Control Link> that turns the foghorn on or off, depending on the weather.

FAQs

What does a <Sound Instance Control Link> control?

A <Sound Instance Control Link> controls the active_sound_value stored in its <Sound Instance>, so that the <Sound Instance> can be turned on and off.

Can a <Sound Instance Control Link> be used to change which <Sound> is accessed by a <Sound Instance>?

No. The link to the <Sound> is an association within the transmittal, and associations cannot be changed dynamically.

Constraints

Composed of (two-way)(inherited)

• one or more {ordered} <Expression> instances

Component of (two-way)

• one or more <Sound Instance> instances

Inherited Field Elements

Field Elements

Notes

Fields Notes

description

 This is a text description of the given <Control Link>
 instance's purpose.

active_sound_value_expr_index

 This specifies the <Expression> component, the value of which
 controls the value of the active_sound_value field of the
 affected <Sound Instance> instance(s). If the controlling
 <Expression> is evaluated to SE_TRUE, the affected <Sound Instance>
 instances are on.