Official forums for BZFlag.org

During the mid-90's, I visited a friend at Columbia (actually Lamont-Doherty Earth Observatory) who had a few SGIs,
and I vaguely remember a Battlezone-like game. As I recall it was played on a tan square, not too big, with something like dark blue pyramids. Since I'd done a port of Battlezone to the PC, I was interested in what it looked like, and spent a little while with it one day.

I can't be more precise as to the year, but was that a forerunner of BZFlag?

mid 90's looks about right.
too bad there aren't any old
screenies to go along with it.

http://bzflag.org/wiki/ProjectHistory

That machine may still be around, and I doubt anyone would have done too much to it - I've sent a request to track it down. For all I know it might still run. (Odds are probably a bit low, but it's worth a try).

My friend at Columbia (Albert) sent this today:

Ok. I found the SGI CD with it. It is on IndiZone 3 dated DEC 1995. The game author is Chris Schoeneman. The IndiZone CDs were the software from a series of game writing contests for the SGI machine. I don't have the SGI running so no screen shot yet....

This looks right; I think he'll grab some screen shots, and maybe could post the binaries somewhere if anyone is interested. Think anyone will be
interested in these historical tidbits?

im interested.

I would be!!

if it's not bzflag, it's probably BZ.
I'd like to see screenies.

I've found binarys of BZ, we are talking to the guy to see if we can get source.

This sounds very exciting, like finding a mummy, or discovering that the PResident is being controlled by mind-sucking aliens..... except its a good thing, I think.

Screenies! I want screenshots!

Use google:


With this request:
Google Images for "battlezone"

that's the arcade game, not the SGI game 'BZ". They are un-related.

What you have there is a screen shot of the game that was the insperation for both bzflag and bz and I'm sure a number of other things.

I did a port of that to Windows, while learning Windows programming, back a few years ago. I didn't quite finish it - there's no sound, for
example, and its interaction with the Windows event loop is pretty poor.
I can probably find that; at one point I posted the source code on the web.

This gives me an idea, which I'll mention in the new features forum.

The Purple Panzer wrote:During the mid-90's, I visited a friend at Columbia (actually Lamont-Doherty Earth Observatory) who had a few SGIs, and I vaguely remember a Battlezone-like game. As I recall it was played on a tan square, not too big, with something like dark blue pyramids. Since I'd done a port of Battlezone to the PC, I was interested in what it looked like, and spent a little while with it one day.

I can't be more precise as to the year, but was that a forerunner of BZFlag?

If it was on the SGI with dark blue pryamids, it most likely actually was bzflag. Just an old version of the game. BZFlag shipped on SGI's as one of their demo apps, so almost *any* SGI box has an old version of bzflag installed on it somewhere. I recently located a copy on an old SGI O2 I have handy -- looks like it's version 1.2 of the game (at least it's protocol BZFS0102, which implies an early 1.x well before the 1.7 days).

And even earlier, in 1990-1993, SGI shipped a demo game called Arena. It had robots that looked vaguely humanoid that you drove in 1st person. The world had a map, similar to bzflag. The map file included a box object that you could jump on, and a central building made from a collection of boxes. The robots, though humanoid, did not walk. They glided around without wheels. They fired simple bullets. And at higher speeds they got shorter, sort of a pseudo-relativistic behaviour, but in the wrong dimension.

Valoche wrote:Use google:


With this request:
Google Images for "battlezone"

funny, I was looking for that exact game when I found bzflag years ago. I didn't know it was Battlezone, I had just done a broad search for any 3-d tank games.

BattleZone was popular in the late 80's in video arcades. If I remember correctly, which I may not, it ran on Atari game machines. It was single-player, no network, but typically had you pitted against 2 tanks at a time.

Each round started with you playing against one or two regular tanks. Once you killed them a few times, you faced one, then two super tanks, which were more angular in design. They turned faster and shot more quickly, and they moved faster than your tank.

Somewhere I have the original binaries for the arcade game, and an emulator to run them on. You're right on the details, but I've pretty much forgotten the rest.

As you approacH relativistic speeds you do get "shorter" (tinier to be more precise).

Gerbil wrote:As you approacH relativistic speeds you do get "shorter" (tinier to be more precise).

You also elongate along the axis of travel as you approach relativistic speeds. But those bots just got shorter vertically, not narrower horizontally, and not longer in direction of travel. Almost as if they were crouching down like a skier.

maybe that's the effect the wanted, the crouching, not the light speed thing .

You shrink in real time as you approach relativistic speeds. It is counter intuitive but true. It's called a "Lorentz contraction" and there are other theorists who have postulated it as well. It has been proven in high speed research aircraft, by the way.

Here's an excerpt from a scientific commentary on the web:

A question sometimes arises: is this contraction real or just an optical illusion of some sort? The answer it is real in every sense. A measurement of something moving will be shorter than of that same object at rest according to every possible test.

So to apply this to BZ, just as a tank "compresses" when it falls from a height, so should tanks shrink when they accelerate with High Speed or Agility (perhaps Thief is in a permanent state of this already?)

Lookie!! I'm a GUNNERY seargeant now--bow to me mortals!

To summarize it, to the 'stationary' observer, the moving person/tank gets smaller only in the direction of motion, becoming effectively two-dimensional at the speed of light. Clocks held by the moving person will appear to slow down, and would appear stopped at the speed of light.

(And, even though it seems impossible, the same thing happens to the observer as seen from the moving person/tank. Neither has a privileged reference frame.)

These consequences follow from the postulate that the speed of light appears the same in all (non-accelerating) reference frames. If you want to work it out yourself, take Maxwell's equations in whichever form you're most comfortable with, do a linear coordinate transformation (say, x => ax' + bt', t=> cx' +dt'), and see what forms the values a, b, c, d have to have to preserve the form of Maxwell's equations in the new frame of reference. If Physics is the same for every observer in every frame, then the form of Maxwell's equations must be the same (the details may differ, as some of the time dimension takes on space-like qualities) - and as a consequence, you find that the (a,b,c,d) values give the length contraction and time dilation that Special Relativity specifies.

Einstein wrote a great little (popular) book called "Relativity", which is well worth a read.

(Oh, and the effects mentioned above will only be observable to humans if the velocity differences are near the speed of light.)

toaster wrote:BattleZone was popular in the late 80's in video arcades. If I remember correctly, which I may not, it ran on Atari game machines. It was single-player, no network, but typically had you pitted against 2 tanks at a time.

Each round started with you playing against one or two regular tanks. Once you killed them a few times, you faced one, then two super tanks, which were more angular in design. They turned faster and shot more quickly, and they moved faster than your tank.

Microsoft purchased all the Atari games and released them, so you can still play the original.

Great game. It inspired the Activision games Battlezone and Battlezone II video games. The gaming clan ( http://www.kovclan.org ) I play with was very active in the game. It has been dieing a slow death for the last 8 years and is all but gone save a few hardcore holdouts.

One thing that is very clear to me is that I haven't used enough of my relativity physics to retain it well. I was remembering the formula:
Length =Length [observed] * sqrt( 1 - (velocity^2 / speed of light^2))

Except for some reason I was thinking that this was inverse, but I did know better. Probably saw one too many Star Trek intros.

As I said in my first response, the robots shrunk only in the vertical dimension. In my second post, I got temporarily stupid. Lorentz contraction still happens along the axis ov movement, the velocity vector. Thanks both of you, Gerbil, and Purple Panzer, for correcting that. In the case of the bots, they were moving forward. They got shorter in height, which is not explained by Lorentz contraction. Lorentz contraction and the Maxwell equations cover projections of the velocity vector alone (or of relative position or length along the travel vector if you want to think about it that way.

JeffM, It's possible that the programmers the programmers meant for them to be appear crouched. But they really just appeared shorter. If so, they didn't do a real good job of it. But who knows?