ISO/IEC 18023-1:200x(E) — Table 6.68 DRM_Elliptic

Table 6.68 — DRM_Elliptic_Cylinder

Property

Description

Class

<DRM Elliptic Cylinder>

Superclass

<DRM Volume Geometry>

Subclass

None.

Definition

An instance EC of this DRM class specifies a closed cylindrical volume with an elliptical cross-section. The <DRM 3D Location> component of EC specifies the centre of the bottom face of EC, where “top” and “bottom” are determined by the spatial reference frame in which EC is specified.

Let E be the ellipse specified by the bottom face of EC. The line passing through the foci of E is termed the major axis of E. The direction of the major axis of E is specified by the component <DRM Reference Vector> of E with vector_type = MAJOR_AXIS.

The line passing through the centre of E and perpendicular to the major axis of E is termed the minor axis of E. The direction of the minor axis of E is specified by the component <DRM Reference Vector> of E with vector_type = MINOR_AXIS.

Class diagram

Figure 6.79 — DRM_Elliptic_Cylinder

Inherited field elements

Field name	Range	Field data type
None

Field elements

Field name	Range	Field data type
major_axis_length ¹	(0.0...)	Long_Float
minor_axis_length ²	(0.0...)	Long_Float
height ³	(0.0...)	Long_Float

Associated to (one-way) (inherited)

None.

Associated to (one-way)

None.

Associated by (one-way) (inherited)

None.

Associated by (one-way)

None.

Associated with (two-way) (inherited)

None.

Associated with (two-way)

zero or one <DRM Geometry Node> instance⁴

Composed of (two-way) (inherited)

zero or one <DRM Classification Data> instance
zero or more {ordered} <DRM Property Set Index> instances
zero or more <DRM Property Table> instances
zero or more <DRM Property Table Reference> instances
zero or more <DRM Property Value> instances
zero or more <DRM Colour> instances
zero or more {ordered} <DRM Image Mapping Function> instances
zero or one <DRM Light Rendering Properties> instance
zero or one <DRM Presentation Domain> instance
zero or one <DRM Rendering Priority Level> instance
zero or one <DRM Rendering Properties> instance
zero or more <DRM Tack Point> instances
zero or one <DRM Union Of Primitive Geometry> instance⁵

Composed of (two-way)

one <DRM 3D Location> instance⁶
exactly 2 <DRM Reference Vector> instances⁷

Composed of (two-way metadata) (inherited)

zero or one <DRM Time Constraints Data> instance

Composed of (two-way metadata)

None.

Component of (two-way) (inherited)

one or more <DRM Union Of Primitive Geometry> instances

Component of (two-way)

None.

Constraints

Clarifications

¹ This is in metres.

² This is in metres.

³ This is in metres.

⁴ For a given instance E of <DRM Elliptic Cylinder>, this corresponds to the <DRM 3D Location> component of E.

⁵ A <DRM Primitive Geometry> contains a <DRM Union Of Primitive Geometry> instance as a component only when that <DRM Primitive Geometry> can be decomposed into nested <DRM Primitive Geometry>, as (for example) a <DRM Polygon> can be decomposed into subfaces.

⁶ For a given instance of <DRM Elliptic Cylinder>, this specifies the centre of the bottom face, where “bottom” is determined by the spatial reference frame in which the <DRM Elliptic Cylinder> is specified.

⁷ For a given instance E of <DRM Elliptic Cylinder>, these are the elliptic cross-section axes of E, such that one <DRM Reference Vector> component has vector_type = MAJOR_AXIS, the other has vector_type = MINOR_AXIS, and the two vectors thus specified are mutually perpendicular.

Example(s)

The physical extent of certain underwater acoustic phenomena such as cold water eddies and fish schools are best described by <DRM Elliptic Cylinder> instances.