Class Name: Color Table Group

Superclass - SEDRIS Abstract Base

Definition

An interchangeable group of one or more Color Tables. The primary Color Table in the group is indicated by the primary_table_index. When a reference is made to a Color Table from somewhere in the transmittal (for example, from an Color Index component of a Polygon), the reference identifies the Color Table Group and the index within the Color Table. Which Color Table within the Color Table Group is not specified. By definition, a Color Index refers to a Primitive Color from the primary Color Table of the indicated Color Table Group. An alternate Color Table from within the Color Table Group can be chosen at the discretion of the end system or run-time system in order to meet the needs of the end system or run-time system.

Primary Page in DRM Diagram:

• 14

Secondary Pages in DRM Diagram:

• 10

Example

1. One Color Table Group in the transmittal, and that group has only one Color Table within the group. That Color Table is the one and only Color Table for the entire transmittal.
2. A Color Table Group with two Color Tables. One Color Table for normal, Out the Window (OTW) viewing, and another Color Table to change the appearance of the view to be a view as seen through Night Vision Goggles (NVG).
3. A Color Table Group with 3 Color Tables with the same usage of OTW. Why 3 tables? One Color Table defines the colors as originally created by the data modelers. The second Color Table has different shades of blue for the lakes and skies because a company VIP came through and didn't like the blues that were there. The third Color Table contains yet another set of blues for the lakes, and different shades of green for the trees and tanks, because the customer in charge of the program came through and didn't think the colors were realistic. In this particular example, it's left as an exercise to the reader to determine which Color Table will be listed first in the Color Table Group and thereby be the default, primary Color Table for the group.

FAQs

Can a transmittal in any way refer to a Color Table in a Color Table Group other than the primary Color Table?

No. The only Color_Table that can be referenced in any Color Table Group is the primary Color Table.

Since you can't refer to them, why bother to have alternate Color Tables within a Color Table Group?

Because in real life, many run-time systems do have multiple color tables they can switch between for various reasons, and these tables should be shared to promote interoperability. See the example section, below.

Constraints

• Color Table Size
• Valid ID Field

Associated by (one-way)

• optionally, some Color Indices

Composed of (two-way)

• one or more {ordered} Color Tables

Composed of (one-way metadata)

• optionally, an Access
• optionally, a Citation
• optionally, some Cross References
• optionally, a Description
• optionally, a Keywords
• optionally, a Point of Contact

Component of (two-way)

• one Color Table Library

Field Elements

Notes

Fields Notes

primary_table_index

 index of the primary <Color Table> component (from the ordered list of
 <Color Table> components in this <Color Table Group>)

table_size

 the size of any and all <Color Tables> within this <Color Table Group>