ISO/IEC 18023-1:200x(E) — Table 6.295 DRM_Union_Of_Geometry

Table 6.295 — DRM_Union_Of_Geometry_Hierarchy

Property

Description

Class

<DRM Union Of Geometry Hierarchy>

Superclass

<DRM Union Of Geometry>

Subclass

None.

Definition

An instance of this DRM class serves to organize <DRM Geometry Hierarchy> instances for which no other organizing principle is suitable.

Class diagram

Figure 6.367 — DRM_Union_Of_Geometry_Hierarchy

Inherited field elements

Field name	Range	Field data type
unique_descendants		Boolean
strict_organizing_principle		Boolean
union_reason		Union_Reason
ordering_reason		Ordering_Reason

Field elements

Field name	Range	Field data type
None

Default field values

Default field values for DRM_Union_Of_Geometry_Hierarchy

Associated to (one-way) (inherited)

zero or more <DRM Feature Representation> instances, each through the use of a <DRM Base Association Data> link object¹
zero or more <DRM Geometry Hierarchy> instances, each through the use of a <DRM Base Association Data> link object²

Associated to (one-way)

None.

Associated by (one-way) (inherited)

zero or more <DRM Feature Representation> instances, each through the use of a <DRM Base Association Data> link object³
zero or more <DRM Geometry Hierarchy> instances, each through the use of a <DRM Base Association Data> link object⁴
zero or one <DRM Hierarchy Summary Item> instance⁵
zero or more <DRM Reference Surface> instances⁶

Associated by (one-way)

None.

Associated with (two-way) (inherited)

None.

Associated with (two-way)

None.

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 one <DRM Reference Surface> instance
zero or more <DRM Sound Instance> instances
zero or more <DRM Base LOD Data> instances
zero or one <DRM Bounding Volume> instance
zero or more <DRM Camera Point> instances
zero or more <DRM Collision Volume> instances⁷
zero or more <DRM Colour> instances
zero or one <DRM Conformal Behaviour> instance
a bounded set of 0..3 <DRM Geometric Centre> instances
zero or more <DRM Geometry Topology Hierarchy> instances
zero or more {ordered} <DRM Image Mapping Function> instances
zero or one <DRM Light Rendering Properties> instance
zero or more <DRM Light Source> instances
zero or one <DRM LSR Transformation> instance⁸
zero or one <DRM Overload Priority Index> instance
zero or one <DRM Perimeter Data> instance
zero or one <DRM Presentation Domain> instance
zero or more <DRM Property Description> instances
zero or one <DRM Rendering Priority Level> instance
zero or one <DRM Rendering Properties> instance
zero or one <DRM Spatial Extent> instance
zero or one <DRM Stamp Behaviour> instance
zero or more <DRM Reference Vector> instances

Composed of (two-way)

one or more {ordered} <DRM Geometry Hierarchy> instances

Composed of (two-way metadata) (inherited)

zero or one <DRM Time Constraints Data> instance
zero or one <DRM Data Quality> instance
zero or one <DRM Identification> instance

Composed of (two-way metadata)

None.

Component of (two-way) (inherited)

zero or more <DRM Alternate Hierarchy Related Geometry> instances, each through the use of a <DRM Hierarchy Data> link object
zero or more <DRM Animation Related Geometry> instances
zero or more <DRM Classification Related Geometry> instances, each through the use of a <DRM Classification Data> link object
zero or one <DRM Environment Root> instance
zero or one <DRM Geometry Model> instance
zero or more <DRM LOD Related Geometry> instances, each through the use of a <DRM Base LOD Data> link object
zero or more <DRM Octant Related Geometry> instances, each through the use of a <DRM Octant Data> link object
zero or more <DRM Perimeter Related Geometry> instances, each through the use of a <DRM Perimeter Data> link object
zero or more <DRM Quadrant Related Geometry> instances, each through the use of a <DRM Quadrant Data> link object
zero or more <DRM Separating Plane Relations> instances, each through the use of a <DRM Separating Plane Data> link object
zero or more <DRM Spatial Index Related Geometry> instances, each through the use of a <DRM Spatial Index Data> link object
zero or more <DRM State Related Geometry> instances, each through the use of a <DRM State Data> link object
zero or more <DRM Time Related Geometry> instances, each through the use of a <DRM Time Constraints Data> link object
zero or more <DRM Union Of Geometry Hierarchy> instances

Component of (two-way)

None.

Constraints

Clarifications

¹An association between a <DRM Feature Representation> instance and a <DRM Geometry Hierarchy> instance indicates that the environmental object(s) that they represent have the semantic relationship indicated by the <DRM Base Association Data> link object on the association relationship.

²An association between two <DRM Geometry Hierarchy> instances indicates that the environmental object(s) that they represent have the semantic relationship indicated by the <DRM Base Association Data> link object on the association relationship.

³An association between a <DRM Feature Representation> instance and a <DRM Geometry Hierarchy> instance indicates that the environmental object(s) that they represent have the semantic relationship indicated by the <DRM Base Association Data> link object on the association relationship.

⁴An association between two <DRM Geometry Hierarchy> instances indicates that the environmental object(s) that they represent have the semantic relationship indicated by the <DRM Base Association Data> link object on the association relationship.

⁵An association from a <DRM Hierarchy Summary Item> instance to a <DRM Geometry Hierarchy> instance indicates that the <DRM Hierarchy Summary Item> instance summarizes that <DRM Geometry Hierarchy> instance.

⁶An association from a <DRM Reference Surface> instance to a <DRM Geometry Hierarchy> instance indicates that the <DRM Geometry Hierarchy> instance organizes the geometric objects that specify the reference surface geometry of the <DRM Reference Surface> instance.

⁷In the case where multiple <DRM Collision Volume> components are specified for the <DRM Aggregate Geometry> instance, the union of the volumes thus specified is used in collision detection.

⁸A <DRM Aggregate Geometry> instance can have a <DRM LSR Transformation> component only when the <DRM Aggregate Geometry> instance is within the scope of an LSR 3D SRF.

Example(s)

An antenna assembly is contained in a weather protection enclosure. Visually, only the opaque enclosure can be seen. But at microwave frequencies, the enclosure is invisible and only the antenna can be seen. The entire structure is contained in a <DRM Union Of Geometry Hierarchy> instance. What the radar sees is modelled with a radar cross-section (RCS) <DRM Property Table> instance. The algorithm (or field measurements) that computed the RCS table used axes that do not match the SRF (world or model as the case may be). Therefore, RCS axes of azimuth and elevation angle are misused unless some <DRM Reference Vector> instances are attached to the entire <DRM Union Of Geometry Hierarchy> instance.