what is virtual reality?(definition) what is differences between opengl & vrml?can u give some web site that give virtual reality example…
The short of it:
VRML is a language that allows describing 3D objects and program interaction with them. It’s designed for the web, and isn’t designed for performance. You can find more about it at http://www.vrml.org/fs_specifications.htm (there are better sites, but I don’t remember them).
OpenGL is a 3D graphics library. You use it as part of a C program (or some other language, but it was originally designed for C) to render 3D. You can find more about it on this site.
Hopefully this gives you some idea how they differ. They’re very different.
Virtual reality is a buzzword, and is used in quite a few ways. I don’t think that there’s a single definition for it, although it basically means that you create a world inside the computer, and let a user interact with it (such as walk in it). I suggest that you forget this buzzword, and think of what you really want to do. Unless of course this is all for some assignment, in which case whoever gave it to you must have his own definition, and I don’t intend to guess it.
Virtual Reality is a much abused term. One event which abused this term more than most was SGI’s naming of VRML, because it really has nothing to do with Virtual Reality, it’s just an ASCII based 3D file format, it’s not even a ‘language’ especially version 1.0.
Virtual Reality if it is anything, is stereoscopic immersion and interractive movement in a 3D scene.
Purists would say that Virtual Reality requires a head tracked HMD (Head Mounted Display), and I tend to agree with them. There’s always someone who will come along and hijack & pervert a nice idea for marketing purposes though. I’d also say that a nice big stereo ‘cave’ counts as Virtual Reality. Calling a big single stereo display (like an immersadesk) virtual reality is a bit of a stretch though.
P.S. These days the term Virtual Reality is used for just about any 3D representation, from computer animation, through computer games to dinky models you can twiddle in your web browser. It’s now completely meaningless because we let the hair heads in the media & marketing departments run amok with the term.
[This message has been edited by dorbie (edited 11-15-2001).]
Virtual reality usually refers to interactive 3D environments (not just pictures which you can scroll over). If you can interact with the environment, and it is 3D then you have the basic virtual reality environment