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The CAVE was developed by Dr. Tom DeFanti in the EVL (web site currently sucky). DeFanti has been in graphics for a long time, even doing all the CG for the original Star Wars. You can find some interesting stuff at Dave's CAVE pages.

The CAVE was developed by Dr. Tom DeFanti in the EVL (web site currently sucky). DeFanti has been in graphics for a long time, even doing all the CG for the original Star Wars. You can find some interesting stuff at Dave's CAVE pages.

While the article had many blundering answers from Gates & Ballmer(C)(TM), and i'm sure most have been picked apart already (450 posts!), one that caught my one was the following...
This is from the 3rd "GATES:" section from the bottom of the page:

So I certainly don't agree with the full sort of free software foundation view that there should be no jobs in this area, and that the kind of commercial advances and risk taking that we've been able to do you can't get that, you can't get things like speech recognition on a tablet computer coming out of that kind of a paradigm.

First of all, let me say... APPLE!!! ever heard of Darwin, that would be the Open Source, fuh-ree version of Mac OS X? - a mighty fine OS if you've ever taken 5 minutes to sit and enjoy it...
and Second Of All, are you implying that university professors and post-docs aren't churning out amazing, GPL'ed advances in Computer Science, like maybe those fabulous molecular modeling apps, or create neat creations like the CAVE with the help of Government and industry and not have to be a vertically integrated illegal monopoly? No Way!!! Say its not so...

Nope, there are some more dates with problems prior to 2038, see this list for some of the more important ones. (I saw a more extensive list once during the pre-Y2K buildup, but those web sites have mostly disappeared. Anyone?)

But I'm sure prices will go down, eventually.

Stefan.

Boy do they have cool stuff there!

The best part was when I got to play with a CAVE . It's a cube about 10ft square with 3D projections on three walls and the floor, which really gives you a feeling of immersion. My favorite program was the cathedral, which imitated the interior of a cathedral (who'd have guessed?). You could "walk" around the interior, which was mostly bare, except for a stairway leading up towards the roof. The stairs had no railing, and I had trouble getting up to the top without falling off. The person who was giving the tour told me that most people's favorite thing was to climb to the top, and then jump off, so I tried it. It's almost as good as a roller coaster! I really got a feeling of falling, as I watched the walls go by, and the floor zoom up at me.

Unfortunately, (well, not really) I got offered a job with Hewlett Packard, and decided to buy a house and have a life instead of being a poor student and playing with really cool geek toys.

I have a set of i-glasses , but they don't even come close to the CAVE in terms of immersion.

Hmmm. I should pull the i-glasses back out of the box and try playing with them again. The only game I ever liked with them was Descent, because it actually worked in 3D. It was pretty neat to strafe around a corner, and be able to see the corner wall with one eye, and an enemy ship with the other eye.

Do any other /.ers have i-glasses? What games do you like to play with them?

Boy do they have cool stuff there!

The best part was when I got to play with a CAVE . It's a cube about 10ft square with 3D projections on three walls and the floor, which really gives you a feeling of immersion. My favorite program was the cathedral, which imitated the interior of a cathedral (who'd have guessed?). You could "walk" around the interior, which was mostly bare, except for a stairway leading up towards the roof. The stairs had no railing, and I had trouble getting up to the top without falling off. The person who was giving the tour told me that most people's favorite thing was to climb to the top, and then jump off, so I tried it. It's almost as good as a roller coaster! I really got a feeling of falling, as I watched the walls go by, and the floor zoom up at me.

Unfortunately, (well, not really) I got offered a job with Hewlett Packard, and decided to buy a house and have a life instead of being a poor student and playing with really cool geek toys.

I have a set of i-glasses , but they don't even come close to the CAVE in terms of immersion.

Hmmm. I should pull the i-glasses back out of the box and try playing with them again. The only game I ever liked with them was Descent, because it actually worked in 3D. It was pretty neat to strafe around a corner, and be able to see the corner wall with one eye, and an enemy ship with the other eye.

Do any other /.ers have i-glasses? What games do you like to play with them?

When I was young and foolish I wasted many an hour blowing Smurfs to hell... The game was called Castle Smurfenstein, and was basically ripped off from Wolfenstein. They claimed that SMURF stood for Secret Military Undergound Resistance Force, and that the smurfs were actually Hitler's last chance at revenge. They would make all the worlds children peace loving and docile, then the smurfs would pop up with submachine guns and blow 'em all away, thereby reviving the third reich...

There is something rather pleasing about sticking a virtual gun in a Smurf's chest, hearing it beg for it's little blue life, and then blowing it to hell... ;-) I may have to go find myself an Apple II emulator and relive my glory days as Smurfbutcher Bob...
Regards,

The description of his Genesis technology seems somewhat familiar to me.
To be specific, it sounds pretty much like the TCP syncookies support in the Linux kernel, however I can't verify that thoroughly because the link to docs that's given in the kernel's config help (ftp://koobera.math.uic.edu/syncookies .ht ml) can't be reached currently.

From the kernel config help:
SYN cookies provide protection against this type of attack (SYN flooding) . If you say Y here, the TCP/IP stack will use a cryptographic challenge protocol known as "SYN cookies" to enable legitimate users to continue to connect, even when your machine is under attack. There is no need for the legitimate users to change their TCP/IP software; SYN cookies work transparently to them.

I am not 100% sure (coz I am too lazy to read the whole article), but this sounds very much like the "SYN cookie" solution now available in the Linux kernel. See this article for a discussion of the principles behind.

Most of the current Ebooks rely on broken structure models designed to exclude unwanted users.

Yes, most of the stuff on Gutenberg is certainly not bestseller material, but they are the trailblazer when it comes to making texts truly open and available.

CAVEs have been connected over Internet 1 for a long time now using the CAVERNSoft library. This is how CAVE Quake II runs its deathmatch.

It's some pretty impressive stuff and quite fun although I find the old mouse + keyboard controls much more responsive. :)

To find out more about the VR "Cave" they're talking about, check out NCSA's CAVERNUS (CAVE Research Network Users Society) site.

I believe this showed up in a /. article about holodecks a while back... :)


---

Electromigration doesn't take place until the chips reach about 170C. This is about 338 fahrenheight. Water boils at 212. Electromigration is a physical phenomenon DIRECTLY linked to heat - it CANNOT occur at low temperatures. It is also worth noting that at around those temperatures the soldering bonds of the PCB starts to break down. But you don't have to take my word for it, look it up for yourself.

One of my electrical engineering professors has a old transistor collection, and you can see a decay in Beta (B) of these devices, so the gain characteristics have changed a fair bit.

That's probably due more to the fact that old transistors only had a sealed metal top on them which due to vibration or over time can become loose (not loose enough for you to notice) and allow the atmosphere to leak in, oxidizing the silicon.

This is _much_ more of a problem in a analog transistor, where the preformance is supposed to be linear.

That's total bunk. Maybe if you had a thick enough marker you could plot it log-log, but "Real Transistors" are distinctly non-linear - see the graph half-way down the page over here. You'll note that the transistor has an area which is fairly linear, but saying that the output of a transistor is linear for any given input is false.

If you overclock, you up the clock rate of a CMOS process. Power consumption goes up correspondingly.

It can't, because the chip's resistance hasn't changed - you didn't increase voltage or current, nor did you reduce the total impedance in the chip (it's the same circuit!) How can power thus increase? Ohm's law doesn't change simply because you increase the frequency.

However, going from 2.2 to 2.4 volts will - assume it was consuming 50W of energy @ 2.2 volts. That means it needs 22 amps. so the chip has a total impedance of 0.1 ohms. Using Ohm's Law, we deduce that an increase to 2.4 volts will give us 24 amps of current - nearly 10% more current!

Not so with monitors. The field is wide open--and overripe, if Sci-fi movie special effects have anything to say about it--for a revoluionary change in the way we view data. Whether it's a 50" flat-screen or a CAVE environment or a holographic projecton, I think things are going to start changing. And it will start changing the way we see things.
--

Here's the original press release:
http://www.uic.edu /depts/paff/opa/releases/retinas_advisory.html

And the company mentioned in the PR, Optiobionics, has a FAQ (which addresses questions of resolution and perception quality for potential patients... in short, they're not sure yet, but it won't be all that great) here.

But do you want a car that says "I think I can, I think I can..."?

The books would have been better than the TV series, but for their many glaring inaccuracies. See the McKinney FAQ, compiled by subscribers to the Robotech mailing lists, for more information.
--

CAVERNUS
- Check out applications to download. My personal favorite is Crayoland. :) There are also some early papers about the CAVE somewhere there

CAVE QUAKE II
- Quake II in the CAVE? What's cooler then that? It's quite unnerving fighting a Tank that's literally taller then you.

Teleimmersion at EVL
- Connecting CAVEs

Welcome to CAVERNsoft
- How to connect CAVEs

Center for Parallel Computers - VR-Cube
- The 6-walled CAVE in sweden. My office-mate saw this, said it was the most immersive experience he's ever done. Forgot where he was!

Ascension Techology Corporation
- These guys make the magnetic tracker we're using.

Welcome to Polhemus!
- another type of tracker

Pyramid Systems
- they'll build a CAVE for ya

AMPRO Corporation
- We use their projectors

CAVE Programming
- Some information on programming for the CAVE

CAVEdev::main
- Some other cool projects for the CAVE

enjoy!

---

CAVERNUS
- Check out applications to download. My personal favorite is Crayoland. :) There are also some early papers about the CAVE somewhere there

CAVE QUAKE II
- Quake II in the CAVE? What's cooler then that? It's quite unnerving fighting a Tank that's literally taller then you.

Teleimmersion at EVL
- Connecting CAVEs

Welcome to CAVERNsoft
- How to connect CAVEs

Center for Parallel Computers - VR-Cube
- The 6-walled CAVE in sweden. My office-mate saw this, said it was the most immersive experience he's ever done. Forgot where he was!

Ascension Techology Corporation
- These guys make the magnetic tracker we're using.

Welcome to Polhemus!
- another type of tracker

Pyramid Systems
- they'll build a CAVE for ya

AMPRO Corporation
- We use their projectors

CAVE Programming
- Some information on programming for the CAVE

CAVEdev::main
- Some other cool projects for the CAVE

enjoy!

---

CAVERNUS
- Check out applications to download. My personal favorite is Crayoland. :) There are also some early papers about the CAVE somewhere there

CAVE QUAKE II
- Quake II in the CAVE? What's cooler then that? It's quite unnerving fighting a Tank that's literally taller then you.

Teleimmersion at EVL
- Connecting CAVEs

Welcome to CAVERNsoft
- How to connect CAVEs

Center for Parallel Computers - VR-Cube
- The 6-walled CAVE in sweden. My office-mate saw this, said it was the most immersive experience he's ever done. Forgot where he was!

Ascension Techology Corporation
- These guys make the magnetic tracker we're using.

Welcome to Polhemus!
- another type of tracker

Pyramid Systems
- they'll build a CAVE for ya

AMPRO Corporation
- We use their projectors

CAVE Programming
- Some information on programming for the CAVE

CAVEdev::main
- Some other cool projects for the CAVE

enjoy!

---

"Since the development of the CAVETM Virtual Reality Theater in 1992, EVL's major area of expertise has been the research and development of software, hardware, networking and communications tools for Virtual Reality."

Projector technology right now sucks for the high end. The CAVE uses CRT projectors (much like the ones in the old big screen TV's) instead of a brighter technology such as LCD, DLP, or Digital Light Valve. Unfortunately, the manufacturers of these brighter products have not pushed the refresh rate limit. In order to use the StereoGraphics shutter glasses, you need at least 100 Hz refresh rate out of your projectors. Currently, the only types of projectors that can handle 100 Hz are CRT's.

These CAVE's are not really multiuser. There are some real problems with perspective in these environments. Only one person can have a corrected view frustrum, and everyone else has to put up with a warping and shearing scene. Of course, this is assuming you are trying to visualize something floating in front of you. This is very hard to describe, but if you think about it, imagine projecting an object floating in front of you, while trying to give your user the ability to walk all around it. Anyhow, this is impossible in any multiuser mode.

CAVE are small. 10'^3 may seem like a lot of space, (as most people's dorm rooms are 12'^3), but oftimes people are limited in movement. This also limits the number of people who can share this experience.

The Electronic Visualization Lab at University of Illinois, Argonne National Labs Futures Lab, and NCSA all have major research going on in CAVE technology.

-Stryemer
We are the music makers,
and we are the dreamers of the dream.

uic's has had a cave for years:
http://www.evl.uic.edu/pape/CAVE/
it sounds alot cooler than it is. its running off some old sgi box or other...

we play cave quake on it. http://hoback.ncsa.uiuc.edu/~prajl ich/caveQuake/ but its not very stable, and the interface needs some work. one cool thing is that your gun is your cursur and its rendered in full 3d instead of just a 2d image. you can twist your gun around and stuff. you have to actualy duck, to duck in the game, and jumping is automated so you end up getting stuck in the walls alot.

The Cave is the big room style VR thing, linking two together may be new, but I doubt it. Whats cool is that the military are using that kind of thing for simulation :)

Reminds me of:

"My butter, garcon, is writ large in!"
a diner was heard to be chargin'.
"I HAD to write there,"
exclaimed waiter Pierre,
"I couldn't find room in the margarine."



For more fermat-poems, see:
http://raphael.math.uic.edu/~jeremy/ poetry.htm

This is funny.

Why are you looking to companies like ATI and 3dfx to build accelerators for realtime simulations? These companies build cards for people who want to play computer games. Duh.

What you need is to rent time in one of The Caves.

There are so many reasons that ASCII is an error. The character set is extremely limited. You can't capture the full formating of the text at all with carriage returns and spaces scattered about.

They really should have moved to a mark-up language as quickly as they could. There is no reason they couldn't have keeped a master copy is SGML marked up with TEI, and then a text version derived from it. If somehow the international standard of SGML disappeared, then the plain text would still be available, and it'd be no worse than it is now.

A quick persual of the web finds the Oxford Text Archive, where the texts were marked up in SGML. Now the texts are available in ASCII, RTF, and HTML. Using existing free software, the texts can also be coverted into TEX, and if you don't like the specifics of the formating above (say you want to remove the page numbers in the HTML because you don't care about it) you can will little effort.

The question here isn't whether to use ASCII, HTML or LaTeX, because there already is a highly developed, sophisticated markup language for electronic text editions, TEI-SGML, specifically designed to preserve all structural information of the original text. Some e-text projects such as the Victorian Women Writers Project code in TEI-SGML. This is not only good for scholars/literature hacks, but also allows lossless reformatting of the source code into HTML, ASCII, PDF, RTF, etc..

The Gutenberg Project certainly was a good idea and a great achievement when it is founded, but might have to rethink its coding policy. Other e-text projects are already doing better here.

Check out the Index of Famous Dog names. "Welcome to Dog Central! The title says it all; this is an Index of Famous Dogs throughout history, both in reality and in fiction. This is not to be considered a complete list, nor can I account for the accuracy of all the information here (just some of it)."

Cats and other critters also available on that site.

(Back in 1982, we needed to move our systems from one building to another. We were told to lose the Star Trek themed names. We picked state names; useful since all of them have two letter abbreviations. "lznv" was the "Nevada" system in the Lincroft building (location code "lz"; dunno what the "z" stood for). It was funny, though, tracing the bus from Hawaii to New Hampshire.-)

Mutt seems to me to have the nicest of the text interfaces; it is somewhat unfortunate that it doesn't have huge support for the multiplicity of folders that a MH user grows to. (I've got 350 mail folders and 179MB of archived email, for instance.) For managing that, the user interface of EXMH combined with a variety of shell scripts are pretty much necessary.

Mutt is still the nicest way of reading mail on a console...

Since nobody's mentioned it so far... Dan Bernstein is the author of
qmail, ezmlm, and lots of other great software. Anyone who
has read the qmail docs or his webpage
will know that he places security above anything else, doesn't
mince his words, and doesn't hesitate to be a nonconformist
(eg, running his web site with his own secure anonymous
FTP server, rather than a http server...)

He's probably among the best possible people for this case.

If there is a lot of data, as might be the case for things like mail routing tables, there is also merit to having a random access mechanism so that the data doesn't have to either be stored in memory or parsed repeatedly.

This is one of the merits of the CDB system; it provides a "binary" form that is rabidly fast but which also can be rewritten from scratch with exceeding rapidity.

Approach that supports both needs:

• When the program that uses the file starts, it "compiles" the text form into binary form.
• When the user signals via SIGHUP, the program "recompiles."
• If the program detects, via date stamps, that the files are out-of-sync (ala "make"), it "recompiles."

The two merit to CDB in this regard are that:

• CDB is really, really, really fast.

  I once "compiled" a file into hashed form, and got about a million keys inserted in 17s on my PPro box.

• CDB does not permit rewriting the DB, as it uses perfect hashing.

  There is no temptation to change the binary form, as you can't modify what has already been written out to it.

  This means that the text form stays as the true data source.

Noticing that the system needs to "recompile" is the one "problem issue" here; it is not exacerbated by this approach as it would be equally true for a purely text-oriented scheme.

Speaking of global floods, you have a shifting definition here. Using the example of Mars, where the amount of liquid water on a global scale may have changed, then yes, the earth has experienced periods where the sea levels have gone up and down by huge amounts, when water has become locked up in large ice sheets. Using the definition of a biblical-style "global flood", many problems arise, not the least of which is, "where did the water go?" :). I recommend looking at http://www.talkorigins.org/faqs/ faq-noahs-ark.html for a discussion of some of the problems with a biblical style global flood.

The problems that science has with young earth creationism are not because scientists refuse to look at the evidence, but instead because they have.

djbfft is located here

Given that copyright law relates to when one is allowed to copy something, attempting to restrict someone's use of a program once they have legally obtained a copy is not something that you can do with a copyright based software license (AFAIK).

Hence, If I download a copy of your code, to have a play with it (i.e. obtain a legal copy). Then, once I have the legal copy, it seems to me that I can quite legally use it to run my business --- I just cannot copy it further, and distribute it.

The only way to enforce this, is to get me to enter into a contract prior to giving me access to the code, in which I agree not to use the software for anything commercial.

Dan Bernsein's take on the situation is probably worth reading, since I'm not a lawyer.

The URL given in the article is wrong. Find the actual page here.

I remember thinking of schemes like this when I first came across the idea of Free Software. I've been thinking about it ever since (about 14 years) and have concluded that they won't work. Given that I make my living out of supporting Free Software, this is not simply an intellectual exercise for me.

The problem is that people are generally not motivated to write good software by money. There is quite a body of evidence that offering monetary incentives to programmers tends to reduce quality, as the programmers start putting effort into working the system, rather than coding. Obviously, people are paid to code, but the money is rarely the direct motivation for doing a good job.

He does touch on one of the primary motivations for commercial programmers contributing to Free Software, which is that it is often cheaper to add the features you want to an existing Free program, than to write, or buy something else.

Anyway, an interesting article, but it's fundamentally flawed in its assumption that COSS falls under the wing of Free Software.

Clause 6 of the DFSG (a.k.a. OSD) prohibits licenses that discriminate against specific fields of endeavour (such as making money, for example).

Even if that were not the case, DFSG compliant licenses must allow derived works (clause 2) which would mean that you could derive a work which differed only in the person to whom the money should be sent, which would instantly destroy the structure he's trying to build.

His ideas also seem to fall foul of the fact that you can do what the hell you like with legally obtained software, so the ``are you using it enough to pay for it ?'' stuff might be interesting to enforce, and certainly wouldn't result in a DFSG license.

On the subject of allocating points, I'd be stunned if anyone could come up with a scheme that would appropriately reward someone that spends six months tracking down an obscure (but serious) bug (say an intermittent networking bug).

Say you allocate 5 points (it's only bug fix, after all) and the contributor says ``that's not enough, I spent six months finding that bug!'' --- You end up with all the silliness of having to do a clean-room reimplementation of the fix ? Oh dear, oh dear.

Dear Judith,

I'd like to apologize for all the mysogynist dorks in this otherwise enlightened community who feel the need to bring up your gender as if it mattered and then denigrate you as if your gender had anything to do with intelligence or courage. I hope these immature yutzes come out of their hovels some day and learn as much about intelligent, courageous women like Clara Barton, Jane Addams, and Maya Angleou (to name a very few) as they have about yacc and gcc.

You don't have to be an antisocial dweeb with blinders on to be a good hacker. Why don't we prove it?

Jason Dufair
"Those who know don't have the words to tell

Shrinkwrap licenses are invalid in the US. See 17 USC 117 and D. J. Bernstein's commentary on the matter.