Table 6.11— DRM_Alternate_Hierarchy_Related_Features

Property

Description

Superclass

·         <DRM Aggregate Feature>

Class

·         <DRM Alternate Hierarchy Related Features>

Subclass

·         none

Definition

An aggregation of <DRM_Feature_Hierarchy> instances in which each component <DRM_Feature_Hierarchy> is an alternate representation of the same environmental entity, and the corresponding <DRM Hierarchy Data> instance indicates why that particular alternate representation was provided.

Example(s)

·         The collection of features representing a specific geographic area is required to be accessed efficiently both by location (e.g., for display), and by classification (i.e., roads, then rivers, then vegetation, etc.). To accommodate this, a <DRM Alternate Hierarchy Related Features> object with two components can be used, in which one component consists of a <DRM Quad Tree Related Features> object, which organizes the <Feature>s by location, and the other component consists of a <DRM Classification Related Features> object, which organizes the features by EDCS Classification Code (ECC).

Inherited field elements

field_name

range

Field_Data_Type

unique_descendants1

 

Boolean

strict_organizing_principle2

 

Boolean

Field elements

field_name

range

Field_Data_Type

none

 

 

Associated to (one-way) (inherited)

·         none

Associated to (one-way)

·         none

Associated by (one-way) (inherited)

·         zero or one <DRM Hierarchy Summary Item>

Associated by (one-way)

·         none

Associated with (two-way) (inherited)

·         zero or more <DRM Feature>s

·         zero or more <DRM Geometry Hierarchy>s

·         zero or more <DRM Property Grid>s

Associated with (two-way)

·         none

Composed of (two-way) (inherited)

·         zero or more {ordered} <DRM Attribute Set Index>s

·         zero or one <DRM Classification Data>

·         zero or more <DRM Colour>s

·         zero or more <DRM Feature Topology Hierarchy>s

·         zero or more (ordered) <DRM Image Mapping Function>s3

·         zero or more <DRM Label>s

·         zero or one <DRM Perimeter Data>

·         zero or one <DRM Presentation Domain>4

·         zero or more <DRM Property Description>s

·         zero or more <DRM Property Table>s

·         zero or more <DRM Property Table Reference>s

·         zero or more <DRM Property Value>s

·         zero or one <DRM Reference Surface>

·         zero or one <DRM Rendering Priority Level>

·         zero or more <DRM Sound Instance>s

·         zero or one <DRM Spatial Domain>

·         zero or one <DRM Time Constraints Data>

Composed of (two-way)

·         two or more <DRM Feature Hierarchy>s through <DRM Hierarchy Data>

Composed of (two-way metadata) (inherited)

·         zero or one <DRM Access>

·         zero or more <DRM Browse Media>s

·         zero or one <DRM Citation>

·         zero or more <DRM Cross Reference>s

·         zero or one <DRM Data Quality>

·         zero or one <DRM Description>

·         zero or one <DRM Keywords>

·         zero or one <DRM Point Of Contact>

Composed of (two-way metadata)

·         none

Component of (two-way) (inherited)

·         zero or more <DRM Alternate Hierarchy Related Features>s through <DRM Hierarchy Data>s

·         zero or more <DRM Classification Related Features>s through <DRM Classification Data>s

·         zero or one <DRM Environment Root>

·         zero or one <DRM Feature Model>

·         zero or more <DRM Level Of Detail Related Features>s through <DRM Base Level Of Detail Data>s

·         zero or more <DRM Oct Tree Related Features>s through <DRM Oct Tree Data>s

·         zero or more <DRM Perimeter Related Features>s through <DRM Perimeter Data>s

·         zero or more <DRM Quad Tree Related Features>s through <DRM Quad Tree Data>s

·         zero or more <DRM Spatial Index Related Features>s through <DRM Spatial Index Data>s

·         zero or more <DRM State Related Features>s through <DRM State Data>s

·         zero or more <DRM Time Related Features>s through <DRM Time Constraints Data>s

·         zero or more <DRM Union Of Features>s

Component of (two-way)

·         none

Constraints

·         Colour mapping restrictions

·         Distinct link objects

·         Image mapping functions and texture coordinates

·         No attribute conflicts

·         Non-crossing aggregations

·         Non-crossing associations

·         Non-cyclic aggregations

·         Precedence of Attribute_Set_Index

Notes

1 If true, for any object that exists 'below' this aggregation, each object will appear in only one 'branch' of this aggregation. If false, objects may appear in multiple 'branches' of this aggregation.

2 If true, each 'branch' strictly follows the rules of this aggregation. If false, each 'branch' might bend the rules a bit. For example, if this is a spatial aggregation, a value of true indicates that objects will not cross the spatial extents defined by this aggregation relationship, and a value of false indicates that objects might cross those bounds.  For another example, if this is a time-based aggregation, a value of true indicates that all branches will only contain data valid for the times specified for each branch, and a value of false indicates that the branches have the option of including data that falls outside of the specified time ranges for that branch.

3 Supports "attributes for derived objects." That is, these components are used only to specify texture mapping information for geometry that

 is derived from the <DRM Aggregate Feature> by the consumer. These <DRM Image Mapping Function>s shall use <DRM Image Anchor> components to specify the mapping.

4 This is needed because in many cases, a <DRM Aggregate Feature> may be significant only for a particular domain, e.g. radar.

Class diagram

<DRM Alternate Hierarchy Related Features>