How is the X3D specification structured?
Because of the new requirements to support multiple file formats and programming languages, X3D is actually comprised of 3 separate ISO specifications: • 19775:200x An abstract description of all the functional parts of the system without reference to any concrete representation. This describes structural and runtime models in abstract terms. External programming language functionality is also expressed in abstract terms as sets of services that can be requested and provided in an ideal world. • 19776:200x A set of file format descriptions of how the abstract structural specification is encoded into files – both text and binary form. Two plain-text file formats are described: Classic VRML (curly brackets form used in VRML97) and XML. Work is underway for a binary format, but is not yet completed. • 19777:200x A set of mappings for various programming languages to the abstract service capabilities. Since not all programming languages are created equal, this specification maps the indivi
