CDB Metadata Files CDB Directory File Naming and Structure

20 © 2016 Open Geospatial Consortium ● Version.xsd

1.4.2.1 The CDB Namespace

The CDB standard makes use of several XML namespaces to isolate the definitions of its schemas. The name of these namespaces is built around a base URL.

1.4.2.2 Schema Conventions

The target namespace of all CDB schemas follow this pattern: http: www.opengis.net cdb[Name][Version] Where the Name is identical to the filename portion of the file containing the schema and Version is the version number of the schema. To illustrate how a target namespace is composed, here is the target namespace of the schema found in Version.xsd item 12 in the list above: http:www.opengis.netcdbVersion1.0 IMPORTANT NOTE: For brevity, the literal “CDB” in a schema path should be expanded to: http: schemas.opengis.netcdb[Name]1.0 in any implementation.

1.4.3 CDB Metadata Files

There are a number of CDB XML files that are referenced from the CDB metadata folder. ● \CDB\Metadata\Lights.xml - CDB Lights ● \CDB\Metadata\Defaults.xml - Default Read and Write values to be used by Simulator Client-Devices

1.4.4 CDB Directory File Naming and Structure

The CDB directory and folder structure is defined by a combination of folder hierarchy and metadata files delivered with the CDB Standard Distribution Package. The CDB folder hierarchy provides a complete list of directory and filename patterns of the CDB; it summarizes the structure of the CDB presented in chapter 3 of this document. The following files are necessary to expand the patterns: ● CDBMetadataFeature_Data_Dictionary.xml provides the list of directory names associated with feature codes. ● CDBMetadataMoving_Model_Codes.xml provides the list of names for DIS Entity Kinds, Domains, and Categories. ● CDBMetadataDIS_Country_Codes.xml contains the list of DIS Country Names. 21 © 2016 Open Geospatial Consortium Together, these files provide all the information required to build the names of all directories permitted by the standard.

1.5 CDB Feature Data Dictionary

The CDB Feature Data Dictionary FDD is provided with the CDB standard in the form of an XML file. An XML Stylesheet is provided to format and display the dictionary inside a standard Web browser. Furthermore, the XML Schema defining the format of the FDD can also be found in the Schema subdirectory of the CDB Schema Distribution Package. See CDBMetadataFeature_Data_Dictionary.xml for the complete list of the supported codes 5 . Please see section 3.3.8.1 for more detailed information on the use of feature codes and extensions to that codelist in the CDB standard.

1.6 Introduction

1.6.1 Purpose

This standard provides a full description of a data model aka schema for the synthetic representation of the world. The representation of the synthetic environment in the CDB model as expressed in a physical data store is intended for use by authoring tools and by various simulator client-devices that are able to simultaneously retrieve, in real-time, relevant information to perform their respective runtime simulation tasks. With the addition of the DIS protocol, the application of the CDB standard provides a Common Environment to which inter- connected simulators share a common view of the simulated environment.

1.6.2 Document Structure

This document is structured as follows. Section 1.6 defines general CDB data store and implementation requirements Sections 2.1, 2.2, 2.3, and 2.4 provide an overview if key elements of the CDB data store structure. Section 2.5: CDB concepts and semantics. Describes the naming and handling of materials that make up the synthetic environment Section 3.0: Focuses on aspects of the data model that relate to the structure of the data store repository on the storage subsystem. The organization of the CDB data into tiles, levels-of-detail and datasets is embodied through a set of conventions that prescribe the CDB directory hierarchy and file naming conventions. Section 4: CDB File Formats provides a description of all the formats prescribed by the CDB Specification. 5 Currenrly, these are FACC codes, Future revisions of the CDB standard shall provide guidance on using other feature code lists.