The SEDRIS Data Representation Model
APPENDIX A - Classes
Line

Class Name: Line

Superclass - <Linear Geometry>

Subclasses

This DRM class is concrete and has no subclasses.

Definition

An instance of this DRM class specifies a sequence of connected line segments, each implicitly specified between the i, i+1 pair of <Base Vertex> components.

Primary Page in DRM Diagram:

Secondary Pages in DRM Diagram:

Example

  1. Consider a <Line> instance L representing a string of 30 evenly spaced lights along one side of a runway.

    To specify what L represents, it has a qualified <Classification Data> component C with tag = ECC_AERODROME_LIGHTING, where C has a <Property Value> component with
    meaning = { SE_ELEM_CODE_TYP_ATTRIBUTE, {EAC_AERONAUTICAL_LIGHT_TYPE}}
    value = { SE_PDV_ENUMERANT_CODE, { EEC_AEROLGTTY_RUNWAY }}.

    L also has a <Light Rendering Properties> component with an appropriate <Flashing Light Behaviour>. L's own field values are count = 30 and suppressLast = SE_FALSE, so that L is rendered as a string of 30 evenly spaced flashing lights.

FAQs

No FAQs supplied.

Constraints

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_Short_Integer_Unsigned count; (notes)
SE_Boolean suppressLast; (notes)

Notes

Composed of Notes


Union_Of_Primitive_Geometry

 A <Primitive Geometry> contains a <Union Of Primitive Geometry>
 instance as a component only when that <Primitive Geometry>
 can be decomposed into nested <Primitive Geometry>, as (for
 example) a <Polygon> can be decomposed into subfaces.

Fields Notes


count

 A value of zero (0) indicates that the given <Linear Geometry>
 instance is to be rendered as solid.

 Otherwise, the interpretation of the count depends on whether
 a <Light Rendering Properties> component is present for
 the given <Linear Geometry> instance.

 - If a <Light Rendering Properties> component is present, then
   count is the number of evenly spaced light points to be
   rendered along the <Linear Geometry>.

 - If no <Light Rendering Properties> component is present, then
   count is the number of evenly spaced line segments to be
   rendered along the <Linear Geometry>.

suppressLast

 If count is greater than zero, this flag indicates whether the
 last segment / point in the sequence is suppressed or rendered.

Prev: Light Source Control Link. Next: Linear Feature. Up:Index.

Last updated: May 15, 2003 Copyright © 2003 SEDRIS™