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LaserMAME: Playing Tempest In A Whole New Light 122

Posted by Hemos from the big-and-beautiful dept.
Effugas writes: "Seen on Zophar is one of the slicker hacks I've seen pulled off in recent memory: LaserMAME. A group of hackers actually patched MAME to drive a Pangolin QM2000 Laser Show Controller Card, allowing them "to play Classic Vector Games on large surfaces, for example we could play it on the side of a building, or possibly on the clouds." Tempest, Battlezone, Asteroids, and many other classics work perfectly--though, unfortunately, the Star Wars classics still don't work correctly. Still, the video is incredible."
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LaserMAME: Playing Tempest In A Whole New Light More

LaserMAME: Playing Tempest In A Whole New Light

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  • The coolest part... (Score:5)

    by Omar ( 12533 ) on Friday October 27, 2000 @05:15AM (#670415)
    Is what they're doing tomorrow...

    Oct 26th, 2000: This Saturday, we are going for the first large scale Trial... In conjunction with our sister Company Light Wave Laser Productions, we will be playing LaserMAME on the side of at least a 6 Story office building, playing from the Club AREA 51, Pittsburgh, PA. 2100 block of Penn St. in the Strip District. Come check it out...
  • ... imagine a BEWOLF of these! You clould play Asteroids on the MOON!

  • someone mirror this, quick. already slow.
  • I feel very sorry for whoever the network admin at shell-o-matic.net is. posting such a tantalising description on slashdot and linking to an obviously low-capacity site... it's going to be ugly. :) - butcher

  • Wow! (Score:1)

    by B00yah ( 213676 )
    They can now take "tetris-on-a-building" on more step...I wonder how far the lasers can go...now all we need is TFC on a building...
  • I preferred the one where they wired up the side of one of the student towerblocks so that they could play 'Tetris' with the lights in the windows...

  • There's only one way to pay homage... (Score:3)

    by AntiPasto ( 168263 ) on Friday October 27, 2000 @05:18AM (#670421) Journal
    pong in the sky.

    ----

  • Oh, the possibilities here (Score:5)

    by Meridun ( 120516 ) on Friday October 27, 2000 @05:19AM (#670422) Homepage
    Doesn't this just beg for someone to set up a game of Missile Command on the side of the Pentagon?

  • How much?
    Rather have this than a PS2!

  • The Nerd-Signal! (Score:4)

    by Electric Angst ( 138229 ) on Friday October 27, 2000 @05:21AM (#670424)
    ...and when the Citizens looked to the sky, they saw the giant vector-graphics in the sky.
    They knew everything would be allright, Nerd-Boy was being called to the Commisioner's Office.
    --
  • And it's what I want for Christmas. You can keep your $15,000 Playstation 2. =)


    --
  • Looking directly at the source of the beam can cause damage, but looking at the beam or the termination point ( the screen or building in this case ) is safe.

    Prolong viewing could possibly have a little effect, but the lasers used here are similar to the ones used in laser shows ( like that one I saw recently with the music of Pink Floyd ).

  • Just a little corection. Penn State is not inPittsburgh, though many people think so, and this would be neat in Beaver stadium. to blind the opposing team and give the Nittany Lions a chance to win.

    You're probably thinking of Pitt.

    That's Penn Street, not Penn State. :-)
  • Could a laser board like used with a phosphor-doped board (to be used as a screen with a little remanence) be used as a tv ?
    Can it scan|display 570 lines 25 times a second(pal) or 480 lines 30 times a second ?
    Will this setup cost less/last longer than an lcd projector ?

    --
  • Now instead of a getting big screen tv so play my Atari games I can just buy a laser.

    So when is laser show quake tournament gonna start?
  • The lasers aren't aimed at your eyes, they're aimed at buildings.

    Now if you were in one of those buildings, and looked out the window right as a asteroid happened to pass, then you'd be in trouble.
    -------

  • Going... Going.... GONE!!!

    Anyone got a mirror?
  • when is laser show quake tournament gonna start?

    This hack only works for vector-based games.

    --

  • go grab the joystick!

    ________

  • It doesn't work with games that aren't just lines. It only works with games that use vector graphics (AKA X-Y monitors), like Asteroids or Lunar lander. For a complete list of games that used vector graphics and more information see this [everything2.com] E2 node.
    -------
  • move over ps2 and nintendo cube. This is neat! Unfortunately, the site is either slashdotted or super slow and i can't see the pictures. Anyone got a mirror? I couldn't find a Google Cached copy of the page or anything....
    back on topic though...I would love to play life size pong. Oh wait..there already is a life size version that is completely immmersive. It feels as if you are actually playing Pong. THe game is called "Table-Tennis" or "Ping-Pong"

  • Sounds cool. What time will you all be doing this?

    Also, happen to have instructions for getting there by bus from Carnegie Mellon? ;)
  • I always thought life sized pong was called Tennis.
    -------
  • The actual laserMame link is:

    http://www.laseremu.com/ [laseremu.com]
  • Lunar Lander on the side of a NASA building!


    Hacker: A criminal who breaks into computer systems

  • my brother and me used to play it down at the bar
    taking money from guys more used to the playing of cards
    with the paddle to the paddle to the side to the side to the paddle to the paddle to the side to the side
    pong
    ball in machine

    now virtually everyone's singing a popular song
    but i still believe in the excellent joy of the pong
    with the side to the side to the paddle to the paddle to the side to the side
    pong
    ball in machine

    now if they take it h.g. wells
    well i'll be on the first flight
    to a time before the kong
    oh whatever happened to pong?
    with the paddle to the paddle to the side to the side to the paddle to the paddle to the side to the side
    pong
    ball in machine
    -- frank black 'whatever happened to pong?'
    (from 'teenager of the year')

    of course i don't know if pong classifies as a vector game..
    ...dave
  • And if one of those buildings had a sign in the window the same color as the laser, you might get some dangerous reflections.

    In college physics we were playing with the Helium lasers, which are a nice, cheery red. Almost the same cheery red as Big Red gum packages, which I conveniently had, as it's good to have fresh breath all the time, you never know when you might meet a nice geek girl you want to impress with your fresh breath, and I've met my share, let me tell you.

    Anyhow, I pulled out my Big Red wrapper, looked at the beam, and intercepted the beam with my Big Red wrapper. Wouldn't you know it, the Big Red wrapper is red because all colors but red get absorbed, red gets reflected. It was cool.

    But, my labmate Scott, into whose eye I reflected the beam, was not amused. Sorry Scott.

  • New at the Museum of Science: Laser Tempest! (Score:3)

    by AFCArchvile ( 221494 ) on Friday October 27, 2000 @05:38AM (#670442)
    This might bring back the allure of those vector-based games of the 80s. It'll be even sharper, since back then anti-aliasing wasn't in use. Hell, the best 3D rendering back then (Tron) was 16-bit non-textured.

    Speaking of which, in the movie Tron, the transition between Tron looking at the MCP's ship and Flynn driving the jalopy recognizer, there's a framerate drop down to 12 FPS. Since it's a cross-fade, the rendering computer had to render both scenes at the same time. Once the first scene fades away, the computer stops rendering it, and the framerate jumps back to 24 FPS.

  • no...life size Table Tennis is Tennis...life size pong is ping pong...Those are rules for life. (an besides..i kick butt and ping pong and i suck at tennis)

  • It is possible to do raster games with a laser controller. My buddy did it 15 years ago -- not actually with a game, but a television image.

    This guy was the ultimate tinkerer. He actually built his own laser light show controller from scratch. The way he did the television image was to set up the mirror controllers to sweep the laser across in lines (that's two mirror controllers). Then, he welded a small piece of metal on a third controller, which could block or let the beam through. It would block the beam in proportion to the brightness of the pixel. It was pretty darn cool.

    I think these guys really need to do some raster games. It's also a lot easier on the beam controllers.


    --

  • low cloud cover (Score:3)

    by photozz ( 168291 ) <photozz&gmail,com> on Friday October 27, 2000 @05:42AM (#670445) Homepage
    hmmmm, let's see, wait for a cloudy day with about a 200' celing, load up missle command and freak out the city. there has to be a law about this somewhere..;)

  • There is only one thing to say... (Score:4)

    by Noryungi ( 70322 ) on Friday October 27, 2000 @05:42AM (#670446) Homepage Journal
    I want one!

    Oh, and can we make a (beowulf) whole block of these?

    Imagine a group of hackers protesting a "no-arcade" local regulation with these mounted on rolling trucks, displaying Tempest on skyscrapers while driving around?
  • You clould play Asteroids on the MOON!

    Other than the fact that you've have to play 3 minutes into the future, while you wait for the light to bounce back from the moon.

    Just play it off Mir instead. Maybe if you charge $5/game you can get enough to keep it in orbit...

  • Video Mirror Up (Score:5)

    by aardwolf64 ( 160070 ) on Friday October 27, 2000 @05:44AM (#670448) Homepage
    You can also view the MPEG at Zophar's Domain [zophar.net] by going here:

    Video File [zophar.net]

  • Rethink your math. It takes 9 minutes for light to get to Earth from the sun. Would it take 3 minutes to go the the moon and come back? I think not.

  • Anti-aliasing is irrelevent... vector displays do not suffer from aliasing.

    Now simulating vector displays on a raster device - that has aliasing issues, but a laser painting on the side of a wall is a pure vector display just like the displays on the old asteroids arcade games.

    Can you imagine playing this on the side of Stone Mountain in Georgia....

  • Why?

    Because I LIVE in pittsburgh, and the Area 51 nightclub is on Penn Ave. There is no area 51 nightclub in state college, sorry- the crowbar just doesn't measure up. The address is right- so he said streat instead of avenue?

    So what? I'm going!
  • Asteroids on an actual asteroid!
    -------
  • How ironic, given that this is /. The reason the Star Wars bit looks like a link, but is unclickable is this: <a href="http://games.lasers.org/images/asteroids.jpg ">Asteroids<a> That's really very disappointing, I think Star Wars would be the primary game I'd want to play. Oh well, maybe they'll get it working soon. Finally, the science museum near my house will be able to turn a profit off of that Laserium equipment :)
  • That's 3 _seconds_, although it's still probably too much to allow you to play.

    The speed of light is c. 186,000 miles/second
    The moon is c. 242,000 miles away

    Rick

  • This might bring back the allure of those vector-based games of the 80s. It'll be even sharper, since back then anti-aliasing wasn't in use.

    Back then, you didn't need anti-aliasing. The CRT's electron gun was directly under the control of the graphics circuitry; i.e. it drew vectors directly, no scanlines. (How else do you think Asteroids got those bullets so damn bright? :-)
  • "Anti-aliasing is irrelevent... vector displays do not suffer from aliasing."

    My point exactly. On TVs and monitors, vector graphics have to be rasterized. Since vector displays aren't bound by an X-by-Y rectangular display, there isn't any aliasing.

    On an offtopic note, in my high school planetarium back in April, I brought in my home computer to show my presentation on Venus and Mars. I projected Q3 on the 50-foot tall dome. Sure, the ultimate Q3 experience, but I was still looking at my monitor; I like CRTs too much.

  • I can see it now!
    What's that on the sky?!?

    A bird?
    A plain?
    No it's .... GAME OVER!

  • Re:There's only one way to pay homage... (Score:4)

    by Jerf ( 17166 ) on Friday October 27, 2000 @05:54AM (#670458) Journal
    This begs for some sort of wistful song...

    When I was just a lad my father gave to me,
    a video game of delicious sim-pli-c-ity,
    with bouncing balls and bleeps and bloops,
    and paddles and switches and scoring loops,
    a game I would remember my whole life long,
    fun... (music sting) thy name is pong.

    I recall the fun I had, playing the hours away,
    pong'ing always was the climax of my day,
    Now I'm a techie and what do I want most?
    A thing to show my nerdy friends, a thing that I can boast,
    Let them look with eyes of green up so very high,
    and envy me my giant game of pong in the sky!

    Chorus: pong in the sky, pong in the sky,
    oh I'd like to play some pong before I die,
    just take your Quake and Diablo and let them fry,
    I just wanna play my pong in the sky!

  • There's a few FPSs have cheats for edge-only graphics ideal for a vector display. I think Turok on the N64 did this, but I don't know any others. It shouldn't be too hard to sort anyway.
  • Correction on the above post... Laser Emulation is a site that keeps news for Laser Emulators, but it not the homepage for LaserMame.

  • As an undergrad years back, we considered putting together a system like this. We were planning to use an obscure game console, the Vectrex (image [wind.ne.jp]; emulator [vintagegaming.com] ) and projecting on the clouds above Los Angeles.

    There are two problems with this approach. First, clouds aren't solid so higher altitude clouds are preferable and higher powered lasers necessary. Secondly, the FAA doesn't like lasers lighting up their airspace and possibly interfering with pilot's vision. The first issue didn't bother us, but lasers have a disadvantage that you can easily track them back to their source.

  • I started watching the video..and in the first five seconds there is a guy typing on a keyboard....is there a reason he is only typing with one hand? seems a little awkward to me.


  • You know it was one thing when it was console game and only a crowd of 3 or so could watch and see how bad I sucked at Tempest.

    There's not a chance in Hell I would play it in front of a crowd of 500.

    In the immortal words of Tim Allen, "I would rather smash my balls flat with a wooden mallet."

  • You could play Asteroids off asteroids! (c=


    --
  • The next time you're planning the pyrotechnic show for a building demolition, think about LaserMAME and MAJOR HAVOC! How cool would that be? Play MAJOR HAVOC on the side of a building in 1:1 scale; when the reactor is triggered on level 13 and the little guy escapes in his space ship, the whole building blows up! You have to admit, MAJOR HAVOC was about the coolest vector game ever, and there could be no more fitting and lifelike way to play it than on the side of a six story building (especially in conjunction with implosive demolition, but be sure to get permission from your parents and/or the building owner.)

  • HOAX! (Score:1)

    by Anonymous Coward
    it's not /.'ed, it's a HOAX!
    remember, you heard it from me first...

    Annonymous Coward -- he will save us all!
  • > wait for a cloudy day with about a 200' celing, load up missle command and freak out the city. there has to be a law about this somewhere..;)

    Sadly, there are. The FAA would get medieval on your ass if you tried it. Lasers and pilots' eyeballs don't mix.

    But if I had the $10K to buy the laser projection system, it just might be worth the fines.

    A possible solution to the FAA problem would be to do it on a boat in international waters, far away from major air traffic routes.

    As cool as the PS2 is, I'd spend $5K as a down payment on LaserMAME before I bought a PS/2!

  • very cool dude! Lets get some lasers in heaven, eh?

    ----

  • vr googles?

    I'M FEELING LUCKY! [slashdot.org]
    ----

  • Don't panic if you're on the west coast! CA Extreme [caextreme.org] will be featuring LaserMAME at the 2001 show.

    So all you Bay Area types who want to get in a weekend of retro gaming will have your chance to see it too, without the trip to PA!

  • 3 seconds... That's good enough to play nethack! We just need to tweak it so shining it on the moon will be visible from earth

    Of course, if we built a laser that powerful... all they would need is a large mirror for a targeting system and they could destroy civilian targets from space. I know, let's fill the dean's house with popcorn and redirect the beam at it! Then everything would be okay, and the new kid would get lucky with the hyperactive geek girl. It can't fail!

  • I'd just love to play this on one of the many buildings here in Southern California contaminated by those cheesey feel good Wyland seascapes. I'm so sick of froliking blue whales and smiling dolphins attacking me every time I drive down the freeway. Imagine playing Ateroids. Forget the chunks of space matter, kill the Whales!

  • Mechanical raster (Score:3)

    by Megane ( 129182 ) on Friday October 27, 2000 @06:11AM (#670473)
    This guy was the ultimate tinkerer. He actually built his own laser light show controller from scratch. The way he did the television image was to set up the mirror controllers to sweep the laser across in lines (that's two mirror controllers).

    Yep, in the early 20th century before CRT displays and cameras had been developed, in the experimental dawn of television, people used mechanical scanners for cameras and displays.

    The problem with vector video games is that you don't have a regular scan like you do with raster, so raster is actually easier to generate with a laser and mirrors because you just need constantly rotating mirrors.

    FWIW, the first home TV recordings (time-shifting, even) were done by recording the analog signal using a wax phonograph recorder. On some examples of these discs, you can visibly see the sync regions, much like you can on a CAV laserdisc.

  • As I posted earlier, there is a mirror to the MPEG file available at Zophar's Domain [zophar.net]:

    http://www.zophar.net/Files/laserm ame NTSC.mpg [zophar.net]
  • When I was somewhere between 6 or 8 (back in 81-83) we actually had a table pong game in the basement. We didn't have any money at the time so I have no freaking idea how we got something like that but we had it. :) I can't tell you how many minutes we wasted playing that game! It had to be something like 20 or 30 minutes! Woo! :)

    -Zane
  • unless of course the reflection off the surface is specular[(like a mirror)(and therefore would preserve the energy density of the initially thin-powerful laser beam)] and not diffuse. but big buildings don't have any surfaces which can cause spec......oh wait.

  • I can understand the FAA's "issues" with projecting lasers up at the sky...

    ... so how the hell does the Luxor at Vegas get away with it? Can't we get whatever permit they must have?

  • Was it just me, or did some of the games have about 100x the flicker as other games in that video? Don't get me wrong, this is waaay cool! But I can just imagine large groups of people dropping the the ground in seizures after looking up and seeing someone playing tempest on the clouds... :)
  • Back in highschool we were setting up a weak neon laser and trying to bounce it all the way around one of the blocks of hallways using mirrors. By the time it got to the second mirror the beam was over 2" in diameter due to distance and a dirty mirror so I was looking at the mirror while aiming it. Our physics "teacher" then got upset and told me to go back into the classroom. I said there was no possible way I could damage my eyes with the beam that diffused but that just pissed him off.

    Oh well, that's what I get for having gym coach as my Physics 2 teacher. God our (American) schools suck.

    -Zane
  • I think the FAA would have an even bigger problem with those pilots that are flying at only 200 feet, eh?
  • So will they be at Burning Man next year?

  • I can see a whole new wave of Vector Graphics games coming out again.

    Since I still love Tempest that is a good thing.

    --ken

  • pfffffft. 3 seconds? That's nothing. Remember when everyone had 28.8's and netquake? Now I hear kids whining about their unplayable 120ms pings. Makes me sick.
  • As near as I can tell, to get the QM2000 board they're talking about, you need to buy Pangolin's LD2000 system (which includes the board and some software). The bargain-basement version (designed for just doing playback of existing stuff and little else) is $2000, which puts it right on par with the PS2's *grin*. I think that's high enough that I can resist the temptation, at least until they get Star Wars working.
  • Actually if you look at the laser vendor site, they show how they can be used to render "raster" graphics - basically bitmaps, and can even be used for video.
  • Maybe I am just slow, but it took me 5 minutes to figure out how this article applied to a military standard regarding unwanted RF eminations.
    -
  • The projector won't have enought horizontal bandwidth. The laser projector works by moving a teeny-tiny mirror back and forth to move the laser around. To scan a simple NTSC requires a horizontal bandwidth of 15kHz. The momentum/inerta of a mirror is much more than that of an electon beam.

  • Does anyone have contact information for these folks available (friggin' web site is /.'ed...)

    I'd really like to get in touch with them about this...

  • Hobyists are pretty much locked out of laser shows as well as open source developers. I just checked the webpage for the processor manufacture. They are proud of the fact the board has a serial number that will play shows written for that serial number board. (dongleware anyone) No wonder laser shows have progressed so slowly. There is no open source one upmanship in the developement circles. Everyone is building from scratch and trying to be best on the market. This makes the shows expensive and amaturish. Just immagine what serious hobyists could do with sharing shows. There would be plenty of great stuff. As example check out some of the great things done with MIDI, clip art, photography, freeware, etc. If all that was avaliable for "shows" was pro written, then all shows would have the uniform feel of a Microsoft Power Point presentation. Anybody else seen all the Microsoft clip art yet. True not everything freeware/opensource/royalty free is fantastic, but you could find just about whatever you need without having to write it from scratch.
  • Pity about the rather expensive controller card and additional bits of hardware this requires (and that they seem to be hoarding the source at the moment).

    Somewhere down along my "hacks to do" list was to try doing something like this on the cheap. Rather than the laser projector, an oscilloscope would provide the vector image. An ordinary sound card would be used to provide the D/A functionality (using the left and right audio channels to drive the X and Y position of the beam), and perhaps a cheap circuit on a bidirectional parallel port to provide beam blanking or brightness (or an additional analogue channel from a second audio card).

    Of course there are problems with accuracy and repeatability when using a sound card for specific D/A conversion, but the initial bit of poking around I did (canned "audio" loops corresponding to image test patterns) suggested that games would at least be recognizable.
  • Ah, how about the side of the vehicle assembly building. You could play from a couple miles away :)
  • Please stop linking to people web sites that cannot handle the slashdot affect. At least warn the sites beforehand becuase they might be running Linux.
  • No faster way to bring a site to its knees than to have Slashdot link to a video.
  • Back in the 60's, the school was given a decision on how to spend the money: swimming pool or planetarium. They opted for the planetarium. Even though the jocks whined back then, there was a dark, domed sanctuary for the nerds of the school.

    Unfortunately, the webpage for the astronomy class hasn't been built yet, so you can't see for yourself. However, it's great to see the elementary school children from around the state come in to see the show. At one point in the standard show for the kiddies, the sky goes cloudy, then lightning strikes (strobe light burst) and you can hear the sound of rain. At that point, Mr. Jameson, the astronomy teacher, runs around with a spray bottle filled with water and sprays at the audience! It's a blast!


  • ....so we take the reference rasterizer source code from the DirectX SDK/DDK and force the HAL call at the bottom of the T&L pipeline to deliver to this engine (forcing wireframe and pretending to handle all texture modes, etc...), than anything that uses D3D will render in mono wireframe on this badboy. I think the actual entry point is called MyRenderPrimitive and it takes a vertex buffer (gotta love MS and their My this and My that...)

    Of course, I have no idea what the vector rendering rates are, but I think if someone published the command interface, it would be a few weekends worth of coding to get it up and running... but still, D3D would run on it...


    ---
    Unto the land of the dead shalt thou be sent at last.
    Surely thou shalt repent of thy cunning.
  • How about this:

    Before posting links to small-time web sites, Slashdot themselves could download a full "mirror" of said site before posting, and include a link to that before the actual site link (or at the top of the article), since their own servers can obviously handle the load. After a week or so, however long it takes for interest to settle down, the mirror could be removed and the original link restored.
  • Oh, and can we make a (beowulf) whole block of these?

    You could definintely use one.... This is a great hack, but for any practical purpose (e.g. laser light shows at high end raves), have a pre-arranged game sequence around. Looking at the apparent refresh rate as viewed on the mpeg, most of these games would be difficult to play as half your playing-time is spent in darkness at one point or another. One imagines that as the screens get more "busy" that the refresh drops even more, making it impossible. Sorry, no Hackers arcade scene here, yet.

    Now, if you got game source, and managed to tweak it so as to distribute the electron gun aim control among more than one laser, each with its own controlling cluster node, you might have better luck at making something thats visually playable.

    Dont get me wrong, this is a fantastic visual stunt with great demonstration applications, but I think they'd better give up the Tempest-on-a-cloud idea.

    (Although... mount this rig on a light helicopter on a calm day, and project Asteroids on a football field. That idea I like. Oh, and hook the rotation and thrust control up to a person in the middle of the field, holding another button to actuate the fire control. Now we're talking.)
  • What about playing from Mir to Earth? :)
  • Probably holding the camera with the other hand. After buying all that laser hardware, I don't think they had much of a budget left for an actual crew. :)

    It's nonsense typing anyway. You can plainly see them hitting the 'T' and 'Y' keys simultaneously.

    Love the shot of the two geeks in front of the Tempest display, pointing at the screen as if we would have missed it otherwise.

  • I am so sick of hearing about this majestic tetris hack, espescially since IT NEVER HAPPENED. The closest anyone can prove is a building VU meter [mit.edu], which was used for "one diminsional" tetris. Neat hack, but nowhere close to being really tetris played on a building.

    This keeps showing up on slashdot, and it keeps getting shot down. See this story [slashdot.org] and search for tetris to read about the enormous difficulties of "building tetris" (I would provide a direct link to the appropriate comments, but they have been archived, and I don't want to just plagerize them).

    Please, please, please, unless you can back something up with evidence (a link to pictures would be a start), quit spreading urban legends. We as geeks are supposed to be more skeptical than the general populous.

    </rant>

  • that's been talked about and talked about over and over. Hunt around for the /. IRC interview. It's a no go. Sites are on their own.
  • Aside from saying "you're an idiot," I can't back it up...though I've seen the pictures. It's been done. If you have some evidence that it never happened...

  • Re:Laser board as BIG-TV (Score:3)

    by jms ( 11418 ) on Friday October 27, 2000 @08:40AM (#670503)
    Right, you can't get back-and-forth motion that fast, so instead you use the same technique that is used in laser printers -- a rotating drum covered with six or eight flat mirrors.

    The laser is reflected off of the mirrors on the drum. As the drum rotates, the angle of the laser with respect to the mirror changes, causing the laser to scan in one direction. When the drum rotates far enough, the laser beam drops off the end of the mirror and strikes the next mirror on the drum. This instantly returns the beam to the starting scan position. No back-and-forth mechanical motion is required, only extremely stable and precise rotational motion.

    Here [pctechguide.com] is a web page with a drawing of how this works in a laser printer.

    Vertical scanning is done the same way. The trick is in keeping both mirror drums rotating at exactly the correct speed and in perfect synchronization with each other.

    As a matter of fact, you could probably use the scanning guts of two laser printer to build a laser-projection TV.

    Now THAT would be a rockin' hack
  • Please give me one technical reason why file transfer via ftp is more efficient than file transfer over http. I'll give you a hint: it isn't. In fact, if you are opening multiple connections with ftp, then it is monstrously more inefficient. There is no magic that ftp is working in order to transfer files better over TCP. FTP is a terrible, deprecated protocol, which should never be used ever. DIE FTP DIE DIE. Thank you.

    -W.W.
  • Erm, it was quite real, it happened 5 minutes down the road from me. Go see http://bastilleweb.techhouse.org/
  • I was wrong. All I wanted was proof.
  • No, it jsut means he goes to school in a rich neighborhood. Supposedly money is distributed to the schools equally, but anyone who knows anything about the US public school system knows that the rich places somehow manage to get all the money. My high school was stuffed in the basement of another school's 50-year-old building, while the people in the foothills get brand-new ten-million-dollar buildings.

    (Not that I would have wanted to switch schools, by any means, but the fact that the school system is so screwed up really annoys me. Government keeps throwing more and more money into it, and yet because of all the corruption nothing happens.)

  • You can contact us as rob@lasers.org
  • I was acutually on the Secondary Engineering team for Beaming Man, but couldn't make it out there. Guess it all depends on how well LaserMAME does Rob
  • Yes it's extremely Dangerous... 5 uSeconds hit from the laser we are using tomorrow night will blind you... We are heavily Regulated by the FDA on Laser Safety... we Had to file a Show Report with the FDA just for the First Test tomorrow night... I don't even know if we got approved yet
  • I think these guys really need to do some raster games. It's also a lot easier on the beam controllers.

    Having actually worked with lasers on a regular basis, and having seen lasers project raster images, I'd like to dissagree.

    While in theory scanning in horizontal lines may sound less taxing, you have a serious problem with the shear amount of data.

    As each point in the image has to be drawn (obviously, it's raster) you have an incredible amount of points... unfortunately the fastest scanners out there can hardly cope with this. Basiclly, you generally get very small, simplified, images of only 1 field (assuming video) and at a low frame rate.

    As far as I know, the only way you could get a solid, quality image, would be to incorporate multiple scan heads - each responsible for a different vertical segment of the screen. (which has been done)

    I am a little sceptical of your friends laser TV... seeing as it seems to be quite the hack, which one would be hard pressed to reproduce given the latest technology.

  • Lasers project decent video + games! (Score:3)

    by ravelasers ( 248364 ) on Friday October 27, 2000 @11:54AM (#670519)
    We have been projecting video-like images with lasers for several years. Since laser images are inherently vector based, we refer to these types of images as raster images. Yes, obvious and redundant. BUT, you must remember that we are using vectors to emulate the other medium. So I suppose it is not such a false nomenclature when you remeber that X-Y TV's get that extra vector prefix!

    The current version of Pangolin's QM2000 (link in earlier post) supports direct projection of any video source -- even a composite input! We routinely project video from a live camera feed at our performances... perhaps those in Pittsburgh this weekend will get a demonstration.

    Althought the best scanners today are projecting 50k points per second, this is measured using a special calibration frame. Since the X scanner is only following a sawtooth waveform, it is possible to more than double this speed. The Y scanner is basically relaxing to provide the vertical waveform. The color control comes from the PCAOM, which modulates the color at >120Khz. The results are stunning. Pangolin's website has great infomation on these techniques:

    Real Time Video [pangolin.com] Raster Info [pangolin.com]

    Thus, ANY video or GAME for that matter could be projected -- but the unique quality of laserMAME is that the format stays entirely in the vector realm, and infinite scalabilty is achieved.

    George Dodworth
    Lightwave International
    lasershows.net [lasershows.net]
  • Nah, Hemos didn't miss anything. I screwed up--and that's pretty infuriating, because I put *alot* of energy into testing my links.

    Ah-duh. Sorry.

    --Dan
  • was getting 1.6 k/s off of shell-o-matic ... am getting 170 k/s off of zophar ... thanks

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