The Virtual Reality Modeling Language Specification Version 2.0 August 4, 1996 The VRML 2.0 Specification An Overview of VRML What is VRML? VRML is an acronym for "Virtual Reality Modeling Language". It is a file format for describing interactive 3D objects and worlds to be experienced on the world wide web (similar to how HTML is used to view text). The first release of The VRML 1.0 Specification was created by Silicon Graphics, Inc. and based on the Open Inventor file format. The second release of VRML adds significantly more interactive capabilities. It was designed by the Silicon Graphics’ VRML 1.0 team with contributions from Sony Research and Mitra. VRML 2.0 was reviewed by the VRML moderated email discussion group ([email protected]), and later adopted and endorsed by a plethora of companies and individuals. See the San Diego Supercomputer Center’s VRML Repository or Silicon Graphics’ VRML site for more information. What is Moving Worlds? Moving Worlds is the name of Silicon Graphics’ submission to the Request-for-Proposals for VRML 2.0. It was chosen by the VRML community as the working document for VRML 2.0. It was created by Silicon Graphics, Inc. in collaboration with Sony and Mitra. Many people in the VRML community were actively involved with Moving Worlds and contributed numerous ideas, reviews, and improvements. What is the VRML Specification? The VRML Specification is the technical document that precisely describes the VRML file format. It is primarily intended for implementors writing VRML browsers and authoring systems. It is also intended for readers interested in learning the details about VRML. Note however that many people (especially non-programmers) find the VRML Specification inadequate as a starting point or primer. There are a variety of excellent introductory books on VRML in bookstores. How was Moving Worlds chosen as the VRML 2.0 Specification? The VRML Architecture Group (VAG) put out a Request-for-Proposals (RFP) in January 1996 for VRML 2.0. Six proposals were received and then debated for about 2 months. Moving Worlds developed a strong consensus and was eventually selected by the VRML community in a poll. The VAG made it official on March 27th. How can I start using VRML 2.0? You must install a VRML 2.0 browser. The following VRML 2.0 Draft browsers or toolkits are available: DimensionX’s Liquid Reality toolkit Silicon Graphics’ Cosmo Player for Windows95 browser Sony’s CyberPassage browser See San Diego Supercomputer Center’s VRML Repository for more details on available VRML browsers and tools. Official VRML 2.0 Specification Changes from Draft 3 to FINAL Compressed PostScript (xxxk) Compressed tar HTML Directory (xxxk) Draft 3 VRML 2.0 Changes from Draft #2b --> #3 Compressed (gzip) Postscript (880K) Compressed (gzip) HTML (140K) Uncompressed HTML (536K) Compressed (gzip) tar HTML dir (952K) PDF format (thanks to Sandy Ressler) Draft 2 VRML 2.0 Compressed (gzip) Postscript (404K) Compressed (gzip) HTML (84K) The Virtual Reality Modeling Language specification was originally developed by Silicon Graphics, Inc. in collaboration with Sony and Mitra. Many people in the VRML community have been involved in the review and evolution of the specification (see Credits). Moving Worlds VRML 2.0 is a tribute to the successful collaboration of all of the members of the VRML community. Gavin Bell, Rikk Carey, and Chris Marrin have headed the effort to produce the final specification. Please send errors or suggestions to [email protected], [email protected], and/or [email protected]. Related Documents VRML 1.0 Specification VRML 2.0: Request-for-Proposal from the VAG VRML 2.0: Process from the VAG VRML 2.0: Polling Results Related Sites VRML Architecture Group (VAG) [email protected] email list information VRML FAQ San Diego Supercomputer Center VRML Repository Silicon Graphics VRML/Cosmo site SONY’s Virtual Society site www-vrml email list archive Contact [email protected], [email protected], or [email protected] with questions or comments. This URL: http://vrml.sgi.com/moving-worlds/index.html An Overview of the Virtual Reality Modeling Language Version 2.0 August 4, 1996 Introduction Summary of VRML 2.0 Features Changes from VRML 1.0 Introduction This overview provides a brief high-level summary of the VRML 2.0 specification. The purposes of the overview are to give you the general idea of the major features, and to provide a summary of the differences between VRML 1.0 and VRML 2.0. The overview consists of two sections: Summary of VRML 2.0 Features Changes from VRML 1.0 This overview assumes that readers are at least vaguely familiar with VRML 1.0. If you’re not, read the introduction to the official VRML 1.0 specification. Note that VRML 2.0 includes some changes to VRML 1.0 concepts and names, so although you should understand the basic idea of what VRML is about, you shouldn’t hold on too strongly to details and definitions from 1.0 as you read the specification. The VRML 2.0 specification is available at: http://vrml.sgi.com/moving-worlds/spec/. Summary of VRML 2.0 Features VRML 1.0 provided a means of creating and viewing static 3D worlds; VRML 2.0 provides much more. The overarching goal of VRML 2.0 is to provide a richer, more exciting, more interactive user experience than is possible within the static boundaries of VRML 1.0. The secondary goal is to provide a solid foundation for future VRML expansion to grow from, and to keep things as simple and as fast as possible -- for everyone from browser developers to world designers to end users. VRML 2.0 provides these extensions and enhancements to VRML 1.0: Enhanced static worlds Interaction Animation Scripting Prototyping Each section of this summary contains links to relevant portions of the official specification. Enhanced Static Worlds You can add realism to the static geometry of your world using new features of VRML 2.0: New nodes allow you to create ground-and-sky backdrops to scenes, add distant mountains and clouds, and dim distant objects with fog. Another new node lets you easily create irregular terrain instead of using flat planes for ground surfaces. VRML 2.0 provides 3D spatial sound-generating nodes to further enhance realism -- you can put crickets, breaking glass, ringing telephones, or any other sound into a scene. If you’re writing a browser, you’ll be happy to see that optimizing and parsing files are easier than in VRML 1.0, thanks to a new simplified scene graph structure. Interaction No more moving like a ghost through cold, dead worlds: now you can directly interact with objects and creatures you encounter. New sensor nodes set off events when you move in certain areas of a world and when you click certain objects. They even let you drag objects or controls from one place to another. Another kind of sensor keeps track of the passage of time, providing a basis for everything from alarm clocks to repetitive animations. And no more walking through walls. Collision detection ensures that solid objects react like solid objects; you bounce off them (or simply stop moving) when you run into them. Terrain following allows you to travel up and down steps or ramps. Animation VRML2.0 includes a variety of animation objects called Interpolators. This allow you to create pre-defined animations of a many aspects of the world and then play it at some opportune time. With animation interpolators you can create moving objects such as flying birds, automatically opening doors, or walking robots, objects that change color as they move, such as the sun, objects that morph their geometry from one shape to another, and you can create guided tours that automatically move the user along a predefined path. Scripting VRML 2.0 wouldn’t be able to move without the new Script nodes. Using Scripts, you can not only animate creatures and objects in a world, but give them a semblance of intelligence. Animated dogs can fetch newspapers or frisbees; clock hands can move; birds can fly; robots can juggle. These effects are achieved by means of events; a script takes input from sensors and generates events based on that input which can change other nodes in the world. Events are passed around among nodes by way of special statements called routes. Prototyping Have an idea for a new kind of geometry node that you want everyone to be able to use? Got a nifty script that you want to turn into part of the next version of VRML? In VRML 2.0, you can encapsulate a group of nodes together as a new node type, a prototype, and then make that node type available to anyone who wants to use it. You can then create instances of the new type, each with different field values -- for instance, you could create a Robot prototype with a robotColor field, and then create as many individual different-colored Robot nodes as you like. Example So how does all this fit together? Here’s a look at possibilities for implementing a fully-interactive demo world called Gone Fishing. In Gone Fishing, you start out hanging in space near a floating worldlet. If you wanted a more earthbound starting situation, you could (for instance) make the worldlet an island in the sea, using a Background node to show shaded water and sky meeting at the horizon as well as distant unmoving geometry like mountains. You could also add a haze in the distance using the fog parameters in a Fog node.