simple.xsd

<?xml version="1.0" encoding="UTF-8"?>
<!-- edited with XMLSpy v2006 sp1 U (http://www.altova.com) by Don Brutzman (Naval Postgraduate School) -->
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified" attributeFormDefault="unqualified" version="3.0.1">
	<!--======================================================================-->
	<!-- Public and private schema extension mechanisms -->
	<xs:include schemaLocation="x3d-3.0-Web3dExtensionsPublic.xsd"/>
	<xs:include schemaLocation="x3d-3.0-Web3dExtensionsPrivate.xsd"/>
	<!--======================================================================-->
	<xs:annotation>
		<xs:appinfo>XML Schema for the Extensible 3D (X3D) Graphics Specification tagset</xs:appinfo>
		<xs:documentation><![CDATA[
=============================================================================

X3D Specification Schema:  	http://www.web3d.org/specifications/x3d-3.0.xsd

Schema extensions:		http://www.web3d.org/specifications/x3d-3.0-Web3dExtensionsPublic.xsd
				http://www.web3d.org/specifications/x3d-3.0-Web3dExtensionsPrivate.xsd

Web3D extensions update URL:	http://www.web3d.org/x3d/content/x3d-3.0-Web3dExtensionsPublic.xsd

Revised:  10 January 2006

Author:   Don Brutzman

Acknowledgements:
- Thanks for excellent insights and assistance from Len Bullard,
  Justin Couch, Leonard Daly, Paul Diefenbach, Rick Goldberg, Bryan Housel,
  Alan Hudson, Chris Lilley, Braden McDaniel, Tony Parisi, Nick Polys,
  Dick Puk, Jeff Sonstein, C. Michael Sperberg-McQueen, Henry Thompson
  and Joe Williams.
- Rick Goldberg of the Sun Java3D team wrote the first two versions of the
  SAI API using IDL, and provided invaluable help on the schema-based SAI.
- Joe Williams of HyperMultiMedia documented and further developed
  the scene graph interface hierarchy, making this schema possible.
- Alan Hudson added many default values and performed consistency checks.

- XML Schema validator:		http://www.w3.org/2001/03/webdata/xsv

Design summary:
- Schemas define XML tagsets in depth using a native-XML format.
- Schemas are an alternative to Document Type Definitions (DTDs).
- This X3D Schema matches the functionality of the X3D DTD and
  provides significant further capabilities, including strong type
  checking of both node and attribute values.
- An XSLT stylesheet can be applied to this schema to autogenerate
  source code for the Scene Authoring Interface (SAI), documentation
  of node lists, etc.

Design patterns:
- X3D nodes implement X3D node types and are represented by XML elements.
- X3D non-node fields are represented by XML attributes using field types.
- X3D field types are represented by XML Schema (xsd) simpleTypes.
- XML Schema list types are used to augment XML Schema simple types, to
  create arrays of X3D base types (integerList etc).
- X3D node types (X3DGroupingNode etc.) are represented by Schema complexTypes.
- X3D node types are captured as XML Schema complexType definitions.  These match 
  the X3D interface hierarchy, capture strong typing of node relationships, and collect 
  common attributes shared among node types.  These features also provide functional 
  consistency between scene graph content and the X3D Scene Authoring Interface (SAI) 
  application programming interface (API).
- XML Schema xs:group element definitions provide child-node content models,
  since complexTypes can't be used as references to unnamed element children.

X3D Schema version numbering:
- 0.4  Nodes for Core and Base profiles (20 November 2000)
- 0.5  Nodes for DIS, GeoSpatial, HumanoidAnimation, Nurbs, any others in Full profile
- 0.6  Autogenerated Scene Authoring Interface (SAI).  First show Java interfaces,
       then show multiple formats including Interface Description Language (IDL)
       and matching Java classes that implement the Java interfaces
- 0.7  Resolution of compromise/compact representations (wrapper tags), and use of