[geovrml] X3D Scene Authoring Interface (SAI) version 0.60 available

[Don Brutzman <brutzman@nps.navy.mil>]

Version 0.60 of the third-generation Scene Authoring Interface (SAI)
is available at 
http://www.web3d.org/TaskGroups/x3d/sai/SceneAuthoringInterface.html

The X3D Scene Authoring Interface (SAI) is an application programming 
interface (API) for the X3D scene graph.  SAI scripts will work for 
Script nodes inside the scene, external applets outside the scene in a 
Web page, Java and EcmaScript (i.e. JavaScript), and for additional
language-independent scripting via XML's Document Object Model (DOM).
SAI profiles for GeoVRML, H-Anim, DIS-Java-VRML and NURBS are included.

Modifications since last time include addition of simple field types,
detailed documentation, and constant enumerations.  ** Most significantly,
the current SAI shows that all methods for setting/getting values are
strongly typed, matching strong typing of the XML (X3D) nodes and fields.  
This means that node-access programming errors are caught at compile time,
rather than later during run time.  Such progress can provide a major 
across-the-board improvement in script reliability and interoperability. **

Version plan:
- 0.4  Nodes for Core and BaseLine profiles (20 November 2000)
- 0.5  Nodes for DisJavaVrml, GeoVrml, H-Anim, 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
       DTD internal parameter-entity names updated to match interface hierarchy
       naming scheme
- 0.8  Exemplar content and authoring tools that correspond to X3D Schema tagset
- 0.9  Public review and Xj3D open-source implementation version
- 1.0  X3D Task Group consensus for inclusion in VRML 200x specification
- 1.1  Web3D Consortium endorsement

Review comments are very important at this stage since further products
are dependent on resolution of open issues.  For example, discussions
regarding whether Site & Joint should be BoundedNodes, what bounding
boxes mean, and other issues which arose from occasional (but unfortunate)
inconsistencies in the VRML 97 spec.  Experts in GeoVRML, H-Anim and NURBS
nodes need to check that the consistent API resolutions in this SAI
are indeed compatible with the various recommended practices.  DIS-Java-VRML
has been checked out OK.  (Any or all of the next five links will do,
since they are consistent.)

Complete Javadoc shows relationships among all of the SAI interfaces. 
http://www.web3d.org/TaskGroups/x3d/sai/javadoc/index.html
The tree diagram is worth additional scrutiny. 
http://www.web3d.org/TaskGroups/x3d/sai/javadoc/org/web3d/x3d/sai/package-tree.html

Joe Williams and I have been working hard to match up every detail with the 
candidate interface hierarchy.  These documents helpfully illustrate details:
http://www.hypermultimedia.com/Xj3D/x3d_candidate_fig.txt
http://www.hypermultimedia.com/Xj3D/x3d_candidate_fig4.txt

The Java interfaces are autogenerated from the draft X3D Schema
http://www.web3d.org/TaskGroups/x3d/translation/X3dSchemaDraft.xml
via an XSLT stylesheet
http://www.web3d.org/TaskGroups/x3d/sai/BuildInterfacesFromSchema.xsl 
Archive available in full at
http://www.web3D.org/TaskGroups/x3d/SaiX3d.zip

As always:  questions, comments and contributions are welcome. 
Discussions occur on the X3D mail list.  Thanks folks.

all the best, Don
-- 
Don Brutzman  Naval Postgraduate School, Code UW/Br Root 200  work 831.656.2149
              Monterey California 93943-5000 USA              fax  831.656.3679
Virtual worlds/underwater robots/Internet     http://web.nps.navy.mil/~brutzman