X3D and HTML5

Goal

The X3D Working Group will participate in the HTML Working Group for the purpose of best integrating X3D with HTML.

This effort has strategic importance for Web3D. We intend to establish a solid foundation for X3D to properly support 3D graphics in HTML5.

HTML5

The HTML working group page states:

       What is HTML?  HTML is the publishing language of the World Wide Web.

The latest editor's draft Hypertext Markup Language (HTML) recommendation states:

       HTML 5 W3C Working Draft
       A vocabulary and associated APIs for HTML and XHTML

       12.2 Declarative 3D scenes
       Embedding 3D imagery into XHTML documents is the domain of X3D,
       or technologies based on X3D that are namespace-aware.

       4.8.5 The object element
       The object element can represent an external resource, which, depending on
       the type of the resource, will either be treated as an image, as a nested
       browsing context, or as an external resource to be processed by a plugin.

       4.8.6 The param element
       The param element defines parameters for plugins invoked by object elements.

Tasks

We are working on the following tasks.

• Ensure that all HTML5 questions and issues relative to X3D are properly considered and answered.
• Document how native X3D in .xml encoding can be best be embedded inside an HTML5 document, typically in a namespace-aware fashion
• Demonstrate X3D+HTML5 examples on the Web3D Consortium website
• Examine how X3D pertains to related HTML5 tags (such as object and canvas) that are used for plugin-type content
• Track MIME type issues
• Examine overall interoperability issues: combined X3D and HTML content with one floating over the other
  • X3D scene with transparent background floating over HTML document or desktop
  • HTML text overlay laid out over an X3D scene as help
• Identify API issues of mutual interest (such as DOM, Ajax and XHR) for further developmental work
• Identify people in HTML5 working group who want to collaborate with us on these issues
• Maintain this X3D and HTML5 wiki page to track issues and progress
• Report regularly on efforts to x3d@web3d.org mailing list and in our every-other-week X3D working group teleconferences
• Discussions to occur on the x3d@web3d.org mailing list
• Other tasks and efforts as needed

Participation

Relevant HTML5 and W3C information:

• HTML Working Group especially Membership and Participation
• World Wide Web Consortium (W3C)
• W3C Process Document

The following individuals have volunteered to serve as X3D Working Group representatives in the HTML5 Working Group.

• Johannes Behr, Fraunhofer Research Darmstadt Germany
• Don Brutzman, Naval Postgraduate School (Web3D-W3C liaison and W3C Advisory Committee representative)
• John Stewart, Communications Research Center (CRC) Canada
• Joe Williams, HyperMultiMedia

Anyone who is interested in serving as one of our representatives is asked to review the HTML working group membership materials, notify the X3D working group that you are interested, and describe what your goals will be.

Meetings

Our next teleconference is 0800-0900 (pacific time) each Tuesday.

We are requesting membership for Web3D participants in W3C HTML5. Don will report to W3C our list of participants, passwords and access will then be provided.

Annotated References

X3D and HTML4

• HTML Object Tag for X3D shows how to place X3D objects within an HTML page
• newHtmlPageWithX3dObject.html is an example HTML scene with X3D object tag to copy, edit and reuse.
• X3D Abstract Specification
• X3D Scene Access Interface (SAI) Edition 2
  • 6.3.13 importDocument service is a utility request to import a W3C DOM document or document fragment and convert it to an X3D scene.

HTML4 and XHTML

• HTML 4.01 HyperText Markup Language (HTML)
• XHTML Extensible HyperText Markup Language

HTML5

• 4.8 Embedded content
  • 4.8.1 The figure element represents some flow content, optionally with a caption, which can be moved away from the main flow of the document without affecting the document's meaning.
  • 4.8.2 The img element represents an image.
  • 4.8.3 The iframe element represents a nested browsing context.
  • 4.8.4 The embed element represents an integration point for an external (typically non-HTML) application or interactive content.
  • 4.8.5 The object element can represent an external resource, which, depending on the type of the resource, will either be treated as an image, as a nested browsing context, or as an external resource to be processed by a plugin.
  • 4.8.6 The param element defines parameters for plugins invoked by object elements. It does not represent anything on its own.
  • 4.8.7 The video element represents a video or movie.
  • 4.8.8 The audio element is a media element whose media data is ostensibly audio data.
  • 4.8.9 The source element allows authors to specify multiple media resources for media elements. It does not represent anything on its own.
  • 4.8.10 Media elements are used to present audio data, or video and audio data, to the user.
  • 4.8.11 The canvas element represents a resolution-dependent bitmap canvas, which can be used for rendering graphs, game graphics, or other visual images on the fly.
  • 4.8.12 The map element, in conjunction with any area element descendants, defines an image map. The element represents its children.
  • 4.8.13 The area element represents either a hyperlink with some text and a corresponding area on an image map, or a dead area on an image map.
  • 4.8.14 Image maps allows geometric areas on an image to be associated with hyperlinks.
  • 4.8.15 MathML from the MathML namespace falls into the embedded content category for the purposes of the content models in this specification.
  • 4.8.16 SVG from the SVG namespace falls into the embedded content category for the purposes of the content models in this specification.
  • 4.8.17 Dimension attributes

API details under discussion

We have discussed Johannes' message of 25 March 2009 + responses (Subject: Re: Khronos Press Releases etc.) that included an X3DOM-connector.pdf diagram regarding how X3D might work with DOM, HTML etc. Also discussed the thread on Khronos' presumed upcoming work on Canvas3D element, and past work on Ajax3D.

These and other API topics are all technically related, and of interest, but have varying degrees of maturity.

The primary objective of the current effort is to support X3D and HTML5. Further work on DOM and other APIs is likely to evolve and spin off from this central effort.

Future work

Some topics might become relevant once HTML5 is established as a formal W3C Recommendation. They are not part of our current planned work.

• Publishing X3D Specifications in HTML5