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| Part One: A Guide to VRML 2.0 |     
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VRML 2.0 is now an International Standard (VRML97). Changes to this specification are unlikely in the immediate future. This is because new functionality can be added to VRML through the use of scripts and prototypes, without requiring any changes to the core language itself.
Any changes to the specification need to be approved by the VRML Consortium, which is advised by the VRML Review Board. Proposals for new standards or recommended practices are developed by the Review Board with the help of Working Groups. Currently there are working groups investigating the follow areas:
- External Authoring Interface (EAI)
Developing standard techniques for allowing Java applets in a HTML document to control a VRML world.
- Compressed Binary Format
Developing a binary format for VRML files will significantly reduce file size and so allow quicker downloading and parsing.
- Streaming
To enable the streaming of geometry and data such as video and audio into a VRML world, so that it can be continuously updated.
- Multi-User Worlds
To define a framework and interface for supporting the virtual presence and interaction of many users in a single scene at the same time.
- Compatibility
Encourage compatibility between different VRML browsers, so that they show and implement worlds in the same way.
- Representation
Develop standard methods for representing humanoid and organic forms.
- Reusable Elements
For example, user interface widgets and universal media libraries than can be held locally.More information about the Working Groups can be found at:
http://www.vrml.org/WorkingGroupsJava3D is an application programming interface (API) being developed by Sun Microsystems for displaying 3D graphics using their Java Language. It will support the VRML 2.0 specification and include a VRML geometry loader and browser tool in the API utility library. See http://java.sun.com/products/java-media/3D/ for more details.
The main discussion forum and source of the latest information about the development of VRML is the www-vrml mailing list. To join the list, send an email to Majordomo@vrml.org. In the message body write:
subscribe www-vrml This is a heavily used mailing list, so you may prefer to receive the digest version instead. Details about this and how to unsubscribe are sent to you when you join.
Archives of the mailing list are available at http://www.vrml.org/www-vrml/hypermail/
VRML has now been firmly established as the standard format for 3D content on the Web. This has been achieved both through its wide spread use and its formal adoption as an international standard by the ISO. It is supported by many of the major companies in the computer industry, through the VRML Consortium. But the involvement of many individuals just commited to the idea of VRML, has played an important part in its development.
The current and future success of VRML depends on two factors, the availability of software and the availability of worlds. This report has shown that many different VRML browsers are now available for viewing VRML 2.0 worlds. They can be obtained for Microsoft Windows (usually 32-bit only), Apple Mac and UNIX systems, and probably just as important, are usually free. The fact that VRML plug-ins are now standard components of the major Web browser distributions is another important factor in making VRML popular. However, there are still a significant problem with incompatibilty, a VRML world may look or behave differently depending on the browser used.
A wide variety of VRML modelling applications and tools are now also available, making world creation easier and not just limited to people with a text editor and an in-depth knowledge of the VRML specification (although that always helps). They range from simple file translators to sophisticated modelling packages, some of which are evaluated in Part Two of this report. Its also worth noting that many widely-used CAD and modelling packages now include VRML export facilities (although often VRML 1.0 only). So, VRML could also become the main file format for exchanging 3D models. However, many of these programs still produce unncessary large or sometimes even incorrect VRML files. Hopefully, these problems will be sorted out in the near future, although its always worth remembering that CAD models don't always make good interactive worlds since they contain too much detail.
The success of a VRML world depends not only on its content, which of course is very important, but also on the time it takes for it to download and whether the user's computer has the power to show it satisfactorily. Large, over complex VRML worlds make interaction slow, unresponsive and ultimately disappointing to everyone except those with the most poweful workstations. Section 5 discussed various techniques for making VRML worlds more efficient. However, computers are becoming more powerful, Intel's MMX technology and the availability of affordable 3D accelerator cards for PCs, creates a large potential audience for VRML.
Will VRML be overtaken by another technology? That is of course possible, but VRML is already well established and can easily be extended to include new features. New technologies, such as Java3D or for creating multi-user 3D worlds will work with VRML rather than attempt to replace it.
Already there are many excellent examples on the Web, that show the power and the exciting potential of the VRML 2.0 language. However, more worlds are still required. Hopefully, this report has provided you with the information necessary to start viewing and creating these worlds.
| Part One: A Guide to VRML 2.0 |
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Graphics Multimedia Virtual Environments Visualisation Contents