Difference between revisions of "X3D and HTML5 Summary"
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| − | + | == Family of [http://www.web3d.org/x3d/specifications X3D Specifications] == | |
| − | + | * X3D Abstract Specification describes basic functionality of how X3D works | |
| − | + | * Three file formats are available: XML (.x3d), ClassicVRML (x3dv), and Compressed Binary Encoding (.x3db) | |
| − | + | * High-performance Application Programming Interfaces (APIs) are defined for Ecmascript-264 (Javascript) and Java | |
| − | + | == X3D Strengths == | |
| − | + | * Non-profit [http://www.web3D.org Web3D Consortium] maintains and extends X3D via working groups | |
| − | + | * Set of International Standards certified over 12-year period by multiple national bodies in ISO | |
| − | + | * Multiple implementations are available (open and commercial source) | |
| − | + | * Numerous resources available online, including specifications themselves | |
| − | + | * Third-generation 3D graphics language that extends predecessor Virtual Reality Modeling Language (VRML97) | |
| − | + | * Long-time W3C member and contributor | |
| − | + | == Web3D Consortium has formal liaisons and working partnerships with other key organizations == | |
| − | + | * [http://www.iso.org International Organization for Standardization (ISO)] | |
| − | + | * [http://www.w3.org World Wide Web Consortium (W3C)] | |
| − | + | * [http://www.opengeospatial.org Open Geospatial Consortium (OGC)] | |
| − | + | * [http://www.khronos.org The Khronos Group] | |
| − | + | * [http://dicom.nema.org Digital Imaging and Communications in Medicine (DICOM)] | |
| − | + | == Relationships between 3D scene graphs, APIs and render layers == | |
| − | + | * Scene graphs are high-level declarative models about how geometry is constructed, colored and animated; these can be expressed as an XML tree | |
| − | + | * APIs are mid-level libraries for programmers to create imperative source code about geometry and animation (various proprietary codebases, perhaps [http://en.wikipedia.org/wiki/WebGL WebGL] or [http://code.google.com/apis/o3d O3D]) | |
| − | + | * Render layers are low-level software libraries that expose the functionality of graphics hardware (e.g. [http://www.opengl.org OpenGL] and [http://en.wikipedia.org/wiki/DirectX DirectX]) | |
| − | + | * Numerous other 3D technologies exist at each of the other layers, often in the form of codebases | |
| − | + | * The X3D Specifications include both declarative models and strongly typed APIs | |
| − | + | == Similarities between MathML, SVG, and X3D == | |
| − | + | * MathML describes mathematical expressions and then renders a presentation of them | |
| − | + | * Scalable Vector Graphics (SVG) describes and presents renderings of 2D shapes, with optional animation and interaction | |
| − | + | * Extensible 3D (X3D) describes and presents renderings of 3D shapes, with optional animation and interaction | |
| − | + | * All three languages are formally specified and have well-developed XML encodings | |
| − | + | * Authors want to use these languages for multimedia content in HTML pages | |
| − | + | == X3D scene graph APIs == | |
| − | + | * X3D Scene Access Interface (SAI) provides functionally consistent standardized high-performance APIs | |
| − | + | * X3D SAI has Ecmascript and Java bindings, other programming languages can be added | |
| − | + | * X3D SAI is functionally equivalent and has same expressive power as file formats (.x3d, .x3dv, .x3db) | |
| − | + | * Document Object Model (DOM) is also legal (X3D is XML after all) but historically has been infrequently used because of low performance | |
| − | + | == Differences with underlying render layers == | |
| − | + | * OpenGL, DirectX, others are used as render layers for output of X3D player which parses .x3d XML files and draws them | |
| − | + | * Unlikely that all browsers will implement the same render layer (OpenGL ≠ DirectX) | |
| − | + | * A Canvas3D layer might be helpful to unify calls to the underlying render layer - but how will it evolve over time? | |
| − | + | * Not clear that Web authors are clamoring for ability to program low-level OpenGl (or similar) source code in Javascript, such models are not interoperable or composable | |
| − | + | * X3D avoids these problems as a declarative scene-graph language available in XML | |
| − | + | == Simple [[X3D and HTML5 examples]] == | |
| − | + | * X3D scene as external reference (Anchor link) | |
| − | + | * X3D embedded in object tag | |
| − | + | * HTML5 with embedded X3D as mixed-namespace document | |
| − | + | * Forthcoming InstantReality [http://www.web3d.org/x3d/specifications X3DOM] javascript demo: html5+x3d with event-passing connections | |
| − | + | * (Can we structure our non-scripted examples to correspond to MathML and SVG examples?) | |
| − | + | == Lessons learned from years developing the [http://freewrl.sourceforge.net FreeWrl] X3D player == | |
| − | + | * Experience: FreeWRL was originally interpreted Perl with specialized "C" functions. Hoped that hardware would improve faster than size of models; that was not the case. | |
| − | + | * Interpreted was not the way to go, rewritten in C for performance | |
| − | + | * Differing OpenGL capabilities: X3D Browsers can handle these, so older models can run efficiently on new hardware (write once, run anytime; even VRML1 models from NASA run fast now) | |
| − | + | * X3D models are not tied to specific hardware, can run over OpenGL-ES, OpenGL-3.2, DirectX11, older standards like OpenGL-1.0... | |
| − | + | * OpenGL requires significant programming skills. Don't know why the average web author would want to code in OpenGL. | |
| − | + | * What does FreeWRL require from Web browser or window? An OpenGL Context (i.e. a number); mouse and keyboard events, window size events, that's about it. | |
| − | + | == Action items for X3D and HTML5 == | |
| − | + | * Ensure proper X3D references in HTML5 specifications - what happened, what happens next? | |
| − | + | * How to allow X3D scene to either reserve screen space or float over the page? Presumably CSS, X3D elements include the class attribute | |
| − | + | * X3D version 3.3 draft is considering SVG and HTML as source for image textures; how to pass events? | |
| − | + | * X3D compression will likely evolve to use Efficient XML Interchange (EXI) | |
| − | + | * Web Accessibility is a future interest | |
| − | + | * Continue to document correct integration and best practices for X3D and HTML5 | |
<!-- Any other recommendations or work issues? --> | <!-- Any other recommendations or work issues? --> | ||
| − | + | == Conclusions == | |
| − | + | * X3D Graphics is a natural fit for HTML5 | |
| − | + | * We want to maximize capabilities and deployment | |
| − | + | * Further collaboration welcome | |
Revision as of 20:20, 5 November 2009
Status: these are draft slides for the X3D and HTML5 working-group effort that will be provided to the Technical Plenary Week (TPAC) 2009.
Contents
- 1 Family of X3D Specifications
- 2 X3D Strengths
- 3 Web3D Consortium has formal liaisons and working partnerships with other key organizations
- 4 Relationships between 3D scene graphs, APIs and render layers
- 5 Similarities between MathML, SVG, and X3D
- 6 X3D scene graph APIs
- 7 Differences with underlying render layers
- 8 Simple X3D and HTML5 examples
- 9 Lessons learned from years developing the FreeWrl X3D player
- 10 Action items for X3D and HTML5
- 11 Conclusions
Family of X3D Specifications
- X3D Abstract Specification describes basic functionality of how X3D works
- Three file formats are available: XML (.x3d), ClassicVRML (x3dv), and Compressed Binary Encoding (.x3db)
- High-performance Application Programming Interfaces (APIs) are defined for Ecmascript-264 (Javascript) and Java
X3D Strengths
- Non-profit Web3D Consortium maintains and extends X3D via working groups
- Set of International Standards certified over 12-year period by multiple national bodies in ISO
- Multiple implementations are available (open and commercial source)
- Numerous resources available online, including specifications themselves
- Third-generation 3D graphics language that extends predecessor Virtual Reality Modeling Language (VRML97)
- Long-time W3C member and contributor
Web3D Consortium has formal liaisons and working partnerships with other key organizations
- International Organization for Standardization (ISO)
- World Wide Web Consortium (W3C)
- Open Geospatial Consortium (OGC)
- The Khronos Group
- Digital Imaging and Communications in Medicine (DICOM)
Relationships between 3D scene graphs, APIs and render layers
- Scene graphs are high-level declarative models about how geometry is constructed, colored and animated; these can be expressed as an XML tree
- APIs are mid-level libraries for programmers to create imperative source code about geometry and animation (various proprietary codebases, perhaps WebGL or O3D)
- Render layers are low-level software libraries that expose the functionality of graphics hardware (e.g. OpenGL and DirectX)
- Numerous other 3D technologies exist at each of the other layers, often in the form of codebases
- The X3D Specifications include both declarative models and strongly typed APIs
Similarities between MathML, SVG, and X3D
- MathML describes mathematical expressions and then renders a presentation of them
- Scalable Vector Graphics (SVG) describes and presents renderings of 2D shapes, with optional animation and interaction
- Extensible 3D (X3D) describes and presents renderings of 3D shapes, with optional animation and interaction
- All three languages are formally specified and have well-developed XML encodings
- Authors want to use these languages for multimedia content in HTML pages
X3D scene graph APIs
- X3D Scene Access Interface (SAI) provides functionally consistent standardized high-performance APIs
- X3D SAI has Ecmascript and Java bindings, other programming languages can be added
- X3D SAI is functionally equivalent and has same expressive power as file formats (.x3d, .x3dv, .x3db)
- Document Object Model (DOM) is also legal (X3D is XML after all) but historically has been infrequently used because of low performance
Differences with underlying render layers
- OpenGL, DirectX, others are used as render layers for output of X3D player which parses .x3d XML files and draws them
- Unlikely that all browsers will implement the same render layer (OpenGL ≠ DirectX)
- A Canvas3D layer might be helpful to unify calls to the underlying render layer - but how will it evolve over time?
- Not clear that Web authors are clamoring for ability to program low-level OpenGl (or similar) source code in Javascript, such models are not interoperable or composable
- X3D avoids these problems as a declarative scene-graph language available in XML
Simple X3D and HTML5 examples
- X3D scene as external reference (Anchor link)
- X3D embedded in object tag
- HTML5 with embedded X3D as mixed-namespace document
- Forthcoming InstantReality X3DOM javascript demo: html5+x3d with event-passing connections
- (Can we structure our non-scripted examples to correspond to MathML and SVG examples?)
Lessons learned from years developing the FreeWrl X3D player
- Experience: FreeWRL was originally interpreted Perl with specialized "C" functions. Hoped that hardware would improve faster than size of models; that was not the case.
- Interpreted was not the way to go, rewritten in C for performance
- Differing OpenGL capabilities: X3D Browsers can handle these, so older models can run efficiently on new hardware (write once, run anytime; even VRML1 models from NASA run fast now)
- X3D models are not tied to specific hardware, can run over OpenGL-ES, OpenGL-3.2, DirectX11, older standards like OpenGL-1.0...
- OpenGL requires significant programming skills. Don't know why the average web author would want to code in OpenGL.
- What does FreeWRL require from Web browser or window? An OpenGL Context (i.e. a number); mouse and keyboard events, window size events, that's about it.
Action items for X3D and HTML5
- Ensure proper X3D references in HTML5 specifications - what happened, what happens next?
- How to allow X3D scene to either reserve screen space or float over the page? Presumably CSS, X3D elements include the class attribute
- X3D version 3.3 draft is considering SVG and HTML as source for image textures; how to pass events?
- X3D compression will likely evolve to use Efficient XML Interchange (EXI)
- Web Accessibility is a future interest
- Continue to document correct integration and best practices for X3D and HTML5
Conclusions
- X3D Graphics is a natural fit for HTML5
- We want to maximize capabilities and deployment
- Further collaboration welcome
