Table 6.268—DRM_Spatial_Index_Related_Features

Property

Description

Superclass

·         <DRM Aggregate Feature>

Class

·         <DRM Spatial Index Related Features>

Subclass

·         none

Definition

An object of this DRM class specifies an aggregation of <DRM Feature Hierarchy>s in which each component <DRM Feature Hierarchy> represents a different tile within a spatially indexed (tiled) organization of <DRM Primitive Feature> objects within a SEDRIS transmittal. The <DRM Spatial Index Data> link object attached to each component <DRM Feature Hierarchy> indicates the tile that it represents.

Example(s)

·         Consider a with row_count = 1, column_count = 4, row_width = 1000 metres, column_width = 500 metres. For simplicity, each of the 4 branches of the in this example is a <DRM Union Of Features>.

Spatial Index Related Organizing Principle, Example 2a

Since the origin of the collection (its lower-left corner, the <DRM AUTM Location 3D> is (0, 0, 0), the coverages of the branches are:

from (0, 0) to (500, 1000)

from (500, 0) to (1000, 1000)

from (1000, 0) to (1500, 1000)

from (1500, 0) to (2000, 1000)

(Note that a <DRM Spatial Index Related Features> does not specify the range of z/height/elevation values.)

Consider a triangular <DRM Areal Feature> in branch #2 of this aggregation, consisting of one <DRM Regular Feature Face>, which in turn has an <DRM External Feature Face Ring> instance containing three <DRM Feature Edge> as follows:

Spatial Index Related Organizing Principle, Example 2b

Since the areal feature crosses the boundary between branch #2 and branch #3, the strict_organizing_principle  of the <DRM Spatial Index Related Features> shall be set to FALSE.

Inherited field elements

field_name

range

Field_Data_Type

unique_descendants1

 

Boolean

strict_organizing_principle2

 

Boolean

Field elements

field_name

range

Field_Data_Type

sparse3

 

Boolean

column_count

 

Integer_Positive

row_count

 

Integer_Positive

column_width4

 

Long_Float

row_width5

 

Long_Float

spacing_units

 

Spatial_Index_Spacing_Unit

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 more <DRM Base Level Of Detail Data>

·         zero or one <DRM Classification Data>

·         zero or more <DRM Colour>s

·         zero or more <DRM Feature Topology Hierarchy>

·         zero or more {ordered} <DRM Image Mapping Function>s6

·         zero or more <DRM Label>s

·         zero or one <DRM Perimeter Data>

·         zero or one <DRM Point Of Contact>

·         zero or one <DRM Presentation Domain>7

·         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 <DRM Location>8

·         one or more <DRM Feature Hierarchy>s through <DRM Spatial Index 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

·         Spatial_Index related organizing principle

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 If FALSE, all column and row entries (all expected <DRM Feature Hierarchy> components) are present. If TRUE, one or more entries are not present.

4 Length of a cell in the given units along the X axis.

5 Length of a cell in the given units along the Y axis.

6 Provided to support "attributes for derived objects." That is, 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 Functions> shall use <DRM Image Anchor> components to specify the mapping.

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

8 The origin of the collection. The lower-left corner.

Class diagram

<DRM Spatial Index Related Features>