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3. \CDB\GTModel\:
This is the entry directory that contains the Geotypical Models Datasets. The directory structure is as defined in Section 3.4, GTModel Library Datasets.
4. \CDB\MModel\:
This is the entry directory that contains the Moving Models Datasets. The directory structure is defined in Section 3.5, MModel Library Datasets.
5. \CDB\Tiles\:
This is the entry directory that contains all tiles within the CDB instance. The directory structure is defined in Section 3.6, CDB Tiled Datasets.
6. \CDB\Navigation\:
This is the entry directory that contains the global Navigation datasets. The directory structure is defined in Section 3.7, Navigation Library Dataset
Most of the CDB datasets are organized in a tile structure and stored under \CDB\Tiles\ directory. The tile structure facilitates access to the information in real-time by the runtime
client-devices. However, for some datasets such as Moving Models or geotypical models datasets that require minimal storage, there is no significant advantage to be added from such a
tile structure. Such datasets are referred to as global datasets; they consist of data elements that are global to the earth, i.e., no structure other than the datasets is provided.
3.1.1 Metadata Directory
There is one directory containing metadata files that are global to the overall CDB structure. \CDB\Metadata contains metadata files that define the various sets of naming hierarchies and
definitions used throughout the CDB. File content is described in Section 5.1, Metadata Datasets. Most metadata files except one are optional and CDB users must implement default
behaviors, according to information contained in this Specification. The \CDB\Metadata directory contains the following metadata files:
1. “Lights” Definitions Metadata file:
This file contains the metadata that defines the light points name hierarchy for the CDB. Refer to Section 2.3, Light Naming, for a description of the light
type hierarchy. A listing of the CDB light type hierarchy can be found in Appendix E. The hierarchy found in Appendix E must be used when
“Lights.xml” is not found in the metadata directory. Refer to section 5.1.1 Light Name Hierarchy Metadata for a description of the light point name
hierarchy file.
2. “Model_Components” Definitions Metadata file:
This file contains the metadata that defines the CDB model components. Refer to Section 2.4, Model Component Naming, for a description of the
model components. A listing of the CDB model components can be found in Appendix F. Refer to section 5.1.2 Model Components Definition Metadata
for a description of the model component file.
3. “Materials” Definitions Metadata file:
This file contains the base material names for the CDB. Refer to Section 2.5,
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Materials, for a description of the CDB materials. A listing of the CDB Base Materials can be found in Appendix L. The base material names found in
appendix L must be used when the “Materials.xml” file is not found in the metadata directory. Refer to section 5.1.3 Base Material Table for a
description of the materials definition file.
4. “Defaults” Definitions Metadata file:
This file contains the default values for each of the CDB datasets. Refer to Chapter 5, CDB Datasets, for a description of the CDB datasets. Appendix S
lists the various default values as documented throughout this Specification. Defaults values found in appendix S must be used if the “Defaults.xml” file is
not found in the metadata directory. Refer to section 5.1.4 Default Values Definition Metadata for a description of the defaults definition file.
5. “Specification_Version” Metadata file deprecated
6. “Version” Metadata file:
This metadata file is mandatory and identifies the content of one CDB Version. The concept is described in section 3.2.1, CDB Version; the content
of the file is defined in section 5.1.6, Version Metadata.
7. “CDB_Attributes” Metadata file:
This file is used to describe all the CDB attributes that are supported by the CDB Specification. A complete listing and description of CDB attributes is
provided in section 5.7.1.3, CDB Attributes of this Specification. The file is described in section 5.1.7 CDB Attributes Metadata.
8. “Geomatics_Attributes” Metadata file:
This file is used to describe all Geomatics attributes that may be referenced by this CDB refer to section 5.7.1.2.6.2, Geomatics Attributes for a description
of Geomatics attributes. Note that the usage of Geomatics attribution falls outside of the jurisdiction of the CDB Specification. Nonetheless, the CDB
Specification provides a standardized mechanism to allow users to fully describe each of the Geomatics attributes they wish to insert within the CDB
repository structure. The file is described in section 5.1.8, Geomatics Attributes Metadata.
9. “Vendor_Attributes” Metadata file:
This file is used to describe all Vendor attributes that may be referenced by this CDB refer to section 5.7.1.2.6.3, Vendor Attributes for a description of
Vendor attributes. Note that the usage of Vendor attribution falls outside of the jurisdiction of the CDB Specification. Nonetheless, the CDB
Specification provides a standardized mechanism to allow users to fully describe each of the Vendor attributes they wish to insert within the CDB
repository structure. The file is described in section 5.1.9, Vendor Attributes Metadata.
10. Client-specific Metadata files:
These files are limited to “Lights_xxx.xml” Definitions Metadata files and offer a complementary approach to modifying the appearance of lights for
