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5.1.2 Model Components Definition File
The CDB standard provides the means to unambiguously tag any portions of a 3D model moving model or cultural feature with a modeled representation with a descriptive name.
Component model names are stored in the model components definition file, “\CDB\Metadata\Model_Components.xml” as described in Section 3.1.1, Metadata Directories.
The XML file containing the CDB Model Components is part of the CDB standard distribution package. The XML schema is provided in \CDB\Metadata\Schema\Model_Components.xsd
delivered with the standard.
The following shows a content sample of the model component definition file:
Model_Components Component name=Artillery_Gun
Description 1 Refers to any engine used for the discharge of large
projectiles and served by a crew of men. 2 Cannon-like weapons operated by more than one person.
Description Component
Component name=Windshield Description
A transparent screen located in front of the occupants of a vehicle to protect them from the wind and weather.
Description Component
... other components Model_Components
5.1.3 Base Materials Table
CDB Base Materials are listed in \CDB\Metadata\Materials.xml and stored in an XML file named \CDB\Metadata\Materials.xml, as mentioned in section 3.1.1. The format of the file is
defined by an XML schema that is delivered with the CDB standard in the file named \CDB\Metadata\Schema\Base_Material_Table.xsd.
Here is an excerpt of the CDB Base Material Table showing the definitions of the first and the last base materials of the standard.
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Base_Material_Table Base_Material
NameBM_ASHName Description
The solid remains of a fire Description
Base_Material ...
Base_Material NameBM_WOOD-DECIDUOUSName
Description Trunks, branches of live deciduous trees
Description Base_Material
Base_Material_Table
5.1.4 Default Values Definition Table
Default values for all datasets can be stored in the default values metadata file “\CDB\Metadata\Defaults.xml” as described in Section 3.1.1, Metadata Directories. Default
values defined throughout the CDB standard are listed in Annex S OGC CDB Core: Model and Physical Structure: Informative Annexes. The XML schema is provided in
\CDB\Metadata\Schema\Defaults.xsd delivered with the standard. There are two types of default values: read and write default values ‘R’ or ‘W’. Generally, read default values are values to
be used when optional information is not available. Write default values are default values to be used by CDB creation tools to fill mandatory content when information is either missing or not
available. The default value name is a unique name identifying a default value for a given dataset. Valid default value names are listed in Annex S. Each default value has a type. Valid
default value data types are “float”, “integer” and “string”.
The following is an excerpt of a “Defaults.xml” file containing the default terrain elevation value.
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Default_Value_Table Default_Value
Dataset001_ElevationDataset NameDefault_Elevation-1Name
DescriptionDefault Primary Terrain ElevationDescription TypefloatType
Value0.0Value R_W_TypeRR_W_Type
Default_Value -- Insert other Default Values in accordance to the table above --
Default_Value_Table
5.1.5 No content 5.1.6 Version Metadata