Continued X3D4 development and use is the focus of discussions within the larger Web3D community. We encourage members to participate in these important discussions as we extend X3D to make native authoring and use of X3D models fully integrated with HTML5.

X3D4 Specification

The latest X3D® version 4 (X3D4) Architecture Specification is a major upgrade to the Extensible 3D (X3D) Graphics International Standard that provides close support for the HTML5 Recommendation, Khronos glTF Physically Based Rendering (PBR), and Web Audio API.  X3D4 is the basis of multiple file encodings and programming language bindings, as illustrated in the X3D Specification Relationships diagram.  The X3D4 Architecture Specification is highly mature, implemented, functionally complete, and undergoing final editorial review for International Standards Organization (ISO).

X3D4 Highlights 

1. X3Dv4 Specification: The X3D 4.0 specification is available to members since 2018 in github; we released a public draft at Web3D/SIGGRAPH 2019, and another update in August 2020. Authors have the archival stability of a well-tested long-lasting specification to build upon. It is the focus of much discussion among the WG meetings and listserves. The X3D Working Group and Web3D Consortium are completing the review and approval process this year, submitting for ISO-IEC ratification in January 2021.  The entire series of corresponding  X3D specifications for file encodings and language bindings will be formally updated to match in 2021.  
2. HTML5 Integration with Javascript APIs:  You can share your 3D models anywhere with anyone by saving them as X3D and then embedding them in an HTML page using either of our open-source implementations, X3DOM and X_ITE. 
3. Multiple file formats and programming languages:  As shown in the X3D Graphics Standards Relationships diagram, X3D 4.0 brings forward our X3D Unified Object Model (X3DUOM) which enables authors to create, validate, and manipulate X3D content in a large number of file encodings (XML, JSON, Binary, ClassicVRML) and programming-language bindings (Javascript, Java, C#, C++, C, Python).
4. glTF Support: X3D 4.0 models can compose scenes with glTF 2.0 assets. Inlining glTF and mapping to the underlying technical structure of X3D. X3D is a higher level scene graph that describes many geometry types, lights, interactions, animations, etc. X3D provides a broader value proposition than glTF, including Metadata and Security. X3D provides a robust presentation layer when combining 3D models, geospatial and imagery into one system. Blog entry Integrating X3D and glTF tells the story and includes links to examples.
5. Physically Based Rendering (PBR) and materials upgrade:  X3D4 includes a new material node (PhysicalMaterial) to describe the surface using the "material-roughness" physical lighting model. X3D PBR supports: Normal maps to all material nodes, a dedicated UnlitMaterial node, support for ambient occlusion textures, and many enhancements to the Phong Material (to customize all the parameters through textures).  Authors can choose classic VRML Phong rendering, advanced PBR or both together for models and composed scenes.
6. Web Audio: Full integration of the Web Audio API (now a Candidate Recommendation by World Wide Web Consortium, W3C) is adding high-fidelity sound propagation, rendering and mixing techniques together with advanced sound processing capabilities.
7. Multiple Implementations: X3DOM and X_ITE continue releases and updates, steadily tracking each X3D 4.0 improvement.  Additional standalone implementations include Castle Game Engine, FreeWRL and other tools.

More details and timelines can be found in the X3Dv4 Overview and X3Dv4 Implementations pages.

Benefits and Opportunities 

1. Benefits of International Standard.  ISO-IEC X3D provides compliance with the US government OMB Circular 119, which states this preference for Standards (and open source technology) contracts and products. X3D (and VRML) fulfill these criteria.  
2. Semantic Web. The X3D Semantic Web Working Group has been meeting bi-weekly and has already produced two peer-reviewed papers. This technical framework shows how X3D can work with the Semantic Web and improve the search-ability of 3D models.  Initial implementations are working with X3Dv4.
3. 3D Printing, 3D Scanning, and CAD Models. X3Dv4 enables 3D printing of models, 3D scanning of objects, and toolchain workflow support for point clouds.  CAD interoperability includes model structure and complete metadata.  X3D can be used in more ways than ever before.
4. Humanoid Animation (HAnim). New HAnim v2 includes Motion Animation.  New examples are being developed.
5. Medical Representations. Using volume visualization, 3D models and metadata, we partner with HealthLevel7 (HL7), DICOM and IEEE 3D Body Processing (3DBP) groups, sharing capabilities to build 3D human and medical records.
6. Partnership work with other standards organizations. Web3D works with ISO and World Wide Web Consortium (W3C) on Web standards.  We also work closely with The Khronos Group on advanced 3D capababilities such as physically based rendering (PBR) and glTF.
7. Heritage  Metadata, Born2B3D, archival publishing of cultural and natural heritage.