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Getting Started in VRML

by Adrian Scott

Answers to Beginners' Questions

The Questions


The Answers

What is VRML?

VRML is Virtual Reality Modeling Language, the open standard for virtual reality on the Internet. VRML files define worlds, which can represent 3D computer-generated graphics, 3D sound, and hypermedia links.

What is VRML useful for?

VRML is useful for a variety of applications, including:

  • data visualization
  • financial analysis
  • entertainment
  • education
  • distributed simulation
  • computer-aided design
  • product marketing
  • virtual malls
  • user interfaces to information
  • scientific visualization
Data visualization turns numbers into a 3D VRML world. It takes a complex database with lots of numerical information and turns it into a three-dimensional environment, which may have a time dimension. Even interactive features and sound can represent information.

Financial analysis can use data visualization to visualize financial data, such as stock prices or corporate financial accounts. Anomalies and opportunities can be detected by highlighted areas in the data set.

Entertainment is a potential goldmine for VRML developers, since VRML allows for interactive, 3D movies. VRML allows customized, dynamically-generated camera angles with alternate scenarios possible.

Education with VRML can give people a chance to learn something in a new way, or learn a real-life job without the dangers of physical machinery.

Distributed Simulation can use multi-user VRML worlds over networks to simulate military exercises or industrial courses.

Computer-Aided Design is an area where designers could collaborate on designing industrial parts or other 3D objects in a shared multi-user space. Or alternatively, they can e-mail parts back and forth to each other, or put drafts up on Web servers for comments.

Product Marketing often tries to reach buyers at an emotional level. VRML is great way to do this, for the same reasons that it will be successful in entertainment applications. In addition, marketers selling 3-dimensional products like clothes can give buyers an impression of the object before they purchase it.

People can shop in Virtual Malls built in VRML.

As User Interfaces to Information, VRML can help bring some sense to the confusing hypermedia world of the Web, and to massive databases packed with more information than can be easily represented textually.

In Scientific Visualization, researchers or students can observe a 3D protein hovering in space and click on parts of it to learn about the function of the parts of the protein through hyperlinks to a database. In fact, Aereal Inc. is currently working on this for the Genetic Information Bank of Japan's Institute of Physical and Chemical Sciences.

How do you view VRML worlds?

To view VRML, you need a VRML browser, helper application or plug-in. The most commonly-used VRML 1.0 browser is Netscape's Live3D, which is available on Windows and PowerMac machines. Their are several VRML 2.0 browsers available in beta form. They include converters that let you view VRML 1.0 worlds as well. VRML 2.0 browsers include Dimension X's Liquid Reality, Silicon Graphics' Cosmo Player and Sony's Community Place (formerly known as Cyber Passage).

Do you need to compile VRML files?

No, you don't need to compile VRML files (just like HTML). When you view the source on worlds that have been compressed with gzip, you may think that they have been compiled, but they have only been compressed. VRML can be created using any text editor (as long as you know the syntax of the language!).

How do you create VRML?

If you know the VRML language, you can actually create VRML in a text editor like notepad or vi -- just like HTML. If you haven't learned VRML or would like an easier way, try out the VRML authoring tools, available from various vendors. (See the answer on authoring software for more info on tools.)

What is the difference between VRML 1.0 and VRML 2.0?

The three main differences are that VRML 2.0 includes 3D sound, interactivity and an object-oriented structure. Interactivity means that objects can move around and respond to the user's actions. For more information, see this month's article, VRML Goes Dynamic, for more information.

How can you make some money/get a job building worlds?

Well, a good place to start is by looking at our new VRMLSite Billboard section, which includes links to several VRML-related companies with openings. Though the market is currently small, most VRML-related companies are trying to hire people. At the same time, not many of those positions are actually for world creators. Many times they are for programmers who write authoring tools, or for marketing people.

Some VRML creators do work on a freelance basis, working on various projects as they come up with different companies. There's not a huge market at this point, but it's gradually growing. Artists who are good at creating 3D models sometimes develop models and sell them to other companies, such as Viewpoint Data Labs.

Others get jobs based on other Web design skills, such as HTML, CGI, Perl, Java, etc., and work some VRML into the equation. Good luck!

Where are the best worlds?

It can be a challenge finding great VRML worlds -- compare it to the challenge of finding cool HTML pages a couple of years ago. One starting point is Proteinman's Top Ten (also available in VRML).

How do you view VRML on a Mac?

There are now several browsers available for Macintoshes, and not just for PowerMacs either. Browsers for 68K Macs include ExpressVR, a Netscape plug-in, and Virtus Voyager, a stand-alone VRML viewer or helper application.

Netscape's Live3D for PowerMac is gradually becoming stable. Other PowerMac software includes ExpressVR, Voyager, Whurlwind, and Equinox.

All of the previous are VRML 1.0 browsers. The new kid on the block is RealSpace, with yes, a VRML 2.0 browser for PowerMacs.

How do you put VRML on a Web server?

You can FTP your VRML file onto a Web server, just as you would with an HTML file. The Web server will serve your file properly only if the MIME type is set up properly in the server.

The MIME type for VRML is "x-world/x-vrml". If you see a pile of text appear when you try to access your world from your server, that means the MIME type is not set up properly. E-mail your webmaster and ask them to set up the MIME type "x-world/x-vrml" for filename extension ".wrl".

In addition, to serve VRML files that have been compressed with GZIP properly, ask your webmaster to set up the Content Encoding type "x-gzip" for filename extension ".gz" (if it's not already set up).

What about multi-user worlds?

Yes, you can have multi-user VRML worlds, using multi-user servers from companies like Integrated Data Systems and Black Sun. Currently, you need to download a special plug-in or browser to experience these multi-user worlds, however it's possible to create multi-user worlds with VRML 2.0, using the Java API.

How do you navigate through a VRML world?

Close your eyes and drag your mouse. But seriously, there are three kinds of modes that most browsers have: fly, walk and point -- but each browser uses slightly different names or styles. In fly-like modes, it's like you are piloting a plane through a 3D space, arrow keys or mouse direction adjusts the direction you're headed in, and you also can move forward and (sometimes) backwards. Walk mode lets you move around on an imaginary flat surface, and you have to press special keys to move up and down.

Point mode is the best (maybe only?) excuse to use a mouse in navigating a VRML environment. You click on an object you see, and then you move towards it. Nice and simple.

Another feature of VRML is that you can have preset viewpoints that a world creator positions to let you look at special vistas or views in the world. Think of it as a movie director positioning a camera while filming a scene. You can usually switch between these by right-clicking and making a selection from a pop-up menu. In addition, there can be links inside the VRML world that link to other parts of the world -- other viewpoints!

It takes a bit of getting used to, but you'll gradually get the hang of it.

How do you make a VRML world have a small file size?

There is one simple way to drastically reduce the file size of your VRML world. You can reduce the file size by 80-90%!! You just need to compress it using GZIP.

GZIP is available for almost all available Unix platforms, plus other machines. Do a search at your favorite search engine to find a version for your machine.

In Unix, if you have gzip, you only need to type: gzip filename.wrl, and your file will become compressed and have the new filename filename.wrl.gz.

How do you combine VRML with Java and JavaScript?

There are several ways to combine VRML with Java and JavaScript. Netscape Live3D users can use Netscape's LiveConnect technology with Live3D to affect a VRML world in an HTML page from a JavaScript function or a Java applet. Conceivably, other browser developers could add LiveConnect interfaces.

In addition, VRML 2.0 has APIs for both Java and JavaScript, so that Java and JavaScript can be referenced through Script nodes. The Java and JavaScript can drive interactivity and other advanced features in the VRML world via the Script node and ROUTE-ing. Sony's Community Place VRML 2.0 browser supports the VRML 2.0 Java API. SGI's Cosmo Player VRML 2.0 browser supports the VRML 2.0 JavaScript API.

Other browsers may have their own Java APIs. Dimension X's Liquid Reality VRML 2.0 browser has its own Java API.

How do you have a VRML world in a frame link to other frames?

In VRML 2.0, you can use the parameters field of the Anchor node with the value "target=frame_name", where frame_name is the name of the frame to be targeted by the link. Note: In VRML 2.0 Draft 2 and earlier, the parameters field was previously called parameter.

Netscape's Live3D VRML 1.0 browser has an extension to VRML 1.0 that lets you target frames. The VRML navigation bar in VRMLSite uses this extension. You can add an extra field called target and give it an SFString value of the name of the frame. In addition, you will want to use a fields parameter in the WWWAnchor node.

What worldbuilding software is available and which is best?

This is a big topic. We recommend checking out VRMLSite's Buyer's Guide Authoring Tools section, and our article on World-building software in our previous issue.

How can you add behaviors without hand editing?

At this point, there are few VRML 2.0 authoring tools available that allow significant behaviors, so you're pretty much stuck using text editors. SGI's Cosmo Create includes some capability. Also, Paragraph's Virtual Home Space Builder provides the capability of creating VRML 2.0 compliant animated textures. Look for VRML 2.0 behavior-authoring software soon from Superscape.

Why do worlds show up as text when you put them on your server?

This happens if the Web server has not been configured to deliver the VRML MIME type. What happens when the MIME type has been set up is that when anyone requests the file from the server, the server puts a little message at the beginning saying that the file is VRML, not text.

For information on how to set up your server for VRML see the answer to the server setup question above.

What are some good books on VRML?

There are three particularly good books on VRML 1.0. These are "VRML Browsing and Building Cyberspace" by Mark Pesce (New Riders), "The VRML Sourcebook" by Ames, Nadeau and Moreland (Wiley), and "Special Edition - Using VRML" by Matsuba and Roehl (QUE). Head to the Books section of our Buyer's Guide for links.


Adrian Scott, adrian@aereal.com, is founder and CEO of Aereal Inc., and publisher of VRMLSite magazine. He's been doing VRML since before he had a VRML browser :). Aereal focuses on Internet Marketing and Publishing, with a particular specialty in using advanced technologies, such as VRML 2.0 and Java. Scott is a co-author or contributing author of six Internet books (including Sams' Unleashed Series).


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