虚拟现实技术

FreeWRL is an open-source(R) VRML and X3D browser written by a group of developers, who wish to produce a high quality, up to date, browser that is in the public domain.

FreeWRL has been placed under the Gnu Library General Public License.

It is written for Unix/Linux and Mac OS/X workstations and while the primary goal of some of the developers is to enable Shared Virtual Worlds, other developers want it to look good, too. So, while the rendering is great, the control of FreeWRL is fantastic. FreeWRL supports Javascript, Java Class invocation, and the EAI version 1 spec. You can control the scene by the mouse, keyboard, joystick, motion sensors, or just about anything you care to patch in - use the existing code base and adapt it for your sensor, and send the new code in!

FreeWRL meets or exceeds the VRML Minimum Conformancy requirements, but there is still some work to be done. Check out the screen shots to see some examples of what you can do.

So, download the code, strap on your Virtual Research goggles, or your ELSA Revelator 3D shutterglasses, and prepare to wander in 3D!

For those of you without shutter glasses, 3D goggles, and other esoteric I/O devices, give it a try with just your mouse and keyboard, ok?

If you use FreeWRL in an interesting project, drop John Stewart a note and tell us about it.

If you want to help develop FreeWRL to use in an interesting project, join the mailing list (send mail to majordomo@mainframe.dgrc.crc.ca with the body containing the message "subscribe freewrl"). Anyone welcome!

Features

FreeWRL is currently still in development stage but has several interesting features:

• Browser support for Mozilla, Konqueror, and others. (Konqueror users have to tell Konqueror to re-configure to find "Netscape" style plugins).
• Unix style "man" page - in a shell, type "man freewrl" to see all options
• H-Anim support - the definitive test, Nancy, is included in the tests directory.
• External Sensor Input - interface anything to your computer, and get it to control your viewpoint! 17 December 1999 - added Polhemus Fastrak input.
• A Descent(tm)-like FLY mode with full 6 degrees of freedom (with 12 keys to control movement).
• A programmatic interface enabling you to make scripts to take snapshots of the world at specific times and places, e.g. for making a movie for non-VRML-enabled people.
• Script node support for both Java and Javascript
• TrueType(tm) font support using the FreeType library
• OpenGL rendering (on Linux using the Mesa library) -- which means hardware aclearcase/" target="_blank" >ccelerated rendering on many systems.
• Open, pluggable framework -- the browser, event model, backend and script engines can all be easily replaced with code to handle new interfaces, e.g. binary VRML, other 3D library interfaces, new scripting languages, whatever.
• Support for most nodes, PROTOs (with events), and Inlines
• Written in a combination of Perl, and standard "C"; Perl allows fast prototyping and nice OO-methodology, while "C" enables quick rendering.