Table 6.47— DRM_Classification_Related_Features

Property

Description

Superclass

·         <DRM Aggregate Feature>

Class

·         <DRM Classification Related Features>

Subclass

·         none

Definition

An aggregation of <DRM Feature Hierarchy> instances, organized according to their EDCS Classification Codes (ECCs), such that each component <DRM Feature Hierarchy> instance represents:

a. a different thematic layer, or

b. a different classification of <DRM Feature> instances within a single thematic layer.

Each branch of a <DRM Classification Related Features> instance therefore has a <DRM Classification Data> instance associated with it as a link object, specifying its (possibly elaborated) classification.

Example(s)

·         Several thematic layers of features might be grouped using a <DRM Classification Related Features> instance, with each of its components representing a separate thematic layer (e.g., culture or vegetation).  The <DRM Classification Data> link object associated with each of its components identifies the contents of each thematic layer, and each of the components is an independent topological complex and has a <DRM Feature Topology Hierarchy>.

·         A region consisting of forest and water is represented as a <DRM Classification Related Features> with strict_organizing_principle set to TRUE, containing two <DRM Union Of Features> components. The first, containing the forest features, has a <DRM Classification Data> link object with tag = FOREST, while the second, containing the water features, has a <DRM Classification Data> link object with tag = WATER.

·         Considering the first example, suppose we have roads running through the forest. We can then replace the forest <DRM Union Of Features> with another <DRM Classification Related Features> having two branches, one classified as ROAD and the other as FOREST.

·         A large collection of features might be organized using a <DRM Classification Related Features> instance, with multiple component <DRM Union Of Features> instances, containing cultural, vegetation, and surface drainage features, respectively.

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 Data>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)

·         one or more <DRM Feature Hierarchy>s through <DRM Classification 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

·         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, then 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 These components are used only to specify texture mapping information for geometry that is derived from the <DRM 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, an <Aggregate Feature> may be significant only for a particular domain, e.g. radar.

Class diagram

<DRM Classification Related Features>