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 VRML (Virtual Reality Modeling Language, usually pronounced vermal)
is a standard file format for representing 3-dimensional (3D)
interactive vector graphics, designed particularly with the World Wide
Web in mind.
Format
VRML is a text file
format where, e.g., vertices and edges for a 3D polygon can be
specified along with the surface color, image-mapped textures,
shininess, transparency, and so on. URLs can be associated with
graphical components so that a web browser might fetch a web-page or a
new VRML file from the Internet when the user clicks on the specific
graphical component. Animations, sounds, lighting, and other aspects of
the virtual world can interact with the user or may be triggered by
external events such as timers. A special Script Node allows the
addition of program code (e.g., written in Java or JavaScript
(ECMAScript)) to a VRML file.
VRML files are commonly
called worlds and have the .wrl extension (for example island.wrl).
Although VRML worlds use a text format they may often be compressed
using gzip so that they transfer over the internet more quickly. Most
3D modeling programs can save objects and scenes in VRML format.
Standardization
The Web3D Consortium has been formed to further the collective development of the format.
The
first version of VRML was specified in November 1994. This version was
specified from, and very closely resembled, the API and file format of
the Open Inventor software component, originally developed by SGI. The
current and functionally complete version is VRML97 (ISO/IEC
14772-1:1997). VRML has now been superseded by X3D (ISO/IEC 19775-1).
Emergence, popularity, and decline
The
term VRML was coined by Dave Raggett in a paper submitted to The First
International Conference on the World-Wide Web in 1994, and first
discussed at the WWW94 VRML BOF established by Tim Berners-Lee, where
Mark Pesce presented the Labyrinth demo he developed with Tony Parisi
& Peter Kennard.
VRML reached the height of its
popularity after the release of VRML2 in 1997, when it was used on some
personal homepages and sites such as CyberTown, which offered 3D chats.
The format had been championed by SGI's Cosmo Software; when SGI
restructured in 1998 the division was sold to Platinum Technologies,
which was then taken over by Computer Associates, which did not develop
or distribute the software. To fill the void a variety of proprietary
Web 3D formats emerged over the next few years, including Microsoft
Chrome and Adobe Atmosphere, neither of which is supported today.
VRML's capabilities remained largely the same while realtime 3D
graphics kept improving. The VRML Consortium changed its name to the
Web3D Consortium, and began work on the successor to VRML - X3D.
While
VRML is still occasionally used, particularly in education and research
where an open specification is most valued, it has now been superseded
by X3D. The MPEG-4 Interactive Profile (ISO/IEC 14496) was based on
VRML (now on X3D), and X3D is largely back-compatible with it. VRML is
also still used as a file format for interchange of 3D models,
particularly from CAD systems.
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