6 ms·

Sega 3-D Glasses: How did they work?

129 points by robin_reala 4y ago

efnx 4y ago
I wish there were more sites like Nicole express. Great job with the break down.
gwbas1c 4y ago
One thing I wish is that the parts of the 3d image were also side-by-side instead of (or in addition to) moving. I trained myself to look at these kinds of things cross-eyed so I can see the 3d effect without glasses.
- jayd16 4y ago
  Even just speeding up the flicker would induce a more 3d effect.
genpfault 4y ago
Not loading for me; archive: https://archive.is/hjChf https://archive.is/hjChf
binarymax 4y ago
I had the (dis)pleasure of using these as a kid. Gave me a wicked headache. But awesome writeup! Reading how they worked I finally understand why I got the headache :)
- ChuckNorris89 4y ago
  Hey, at least you got to experience the ...puts on shades... Segaverse.
- allenu 4y ago
  Did you ever try plying them without the glasses? Now that’s a headache! I had a Master System as a kid and was disappointed when I purchased Maze Hunter 3D and brought it home only to find I could not play it without the glasses. No wonder they were discounted. However, I did read in a book that Space Harrier 3D had an Easter egg that allowed you to disable the 3D feature, but you had to get on the high score screen to execute the code. I ended up buying that at a discount. I got quite good at getting through the first level of the game without the 3D glasses.
  - nsxwolf 4y ago
    Zaxxon 3D also let you turn off the 3D. Not sure why all the games didn't. There's no good way to play them today without the peripheral and a CRT.
  - cholmon 4y ago
    I had a Master System as well, but my glasses broke early on in my ownership, so I played Maze Hunter, Blade Eagle, and Missile Defnce without them. Eventually, I got accustomed to the odd look of everything being slightly doubled. When I finally got a new pair of glasses that worked, the 3D gameplay felt so odd that I preferred playing without them.
ytreyrty 4y ago
will 3D/VR ever really become mainstream? i recently bought a PSVR2, the tech seemed amazing but i had to return it due to horrible motion sickness. we're at almost 30 years of the tech still not being ready for prime time.
- edent 4y ago
  Not until they overcome the need for the viewer to do something. Moving from mono sound to stereo doesn't require anything of the listener. Going from black and white to colour doesn't require you wear special equipment. But 3D? You have to put on special glasses which you also have to remember to charge. Oh, and you can't look at other things while you're using them. There were some passive 3D displays (the Nintendo 3DS and a few early Android phones) but they required the user to stay in exactly the right position, or the illusion was destroyed. So you couldn't easily share the experience with a friend. Until we have TVs which can shoot lasers directly into our eyeballs, I think the barrier to entry is too high.
  - sudosysgen 4y ago
    These kinds of VR headsets don't need to be charged (they are wired) and you can press a button to see the real world through the cameras.
    - edent 4y ago
      So now I need to be physically tethered to my seat? Do I press the button on the left or the right? Is it one tap to see the real world or two?
      - sudosysgen 4y ago
        The cable is long enough that your room will run out before you run out of cable, so no need to be tethered to your seat. Generally to pass through the real world you'd do something like simulatenously press two easily accessible buttons on your tracked controller. It is really very easy and I use it often.
mardifoufs 4y ago
>240p is fake and a lie, but close enough for us I want to know more :) and my googling skills are failling me. But I didn't even realize you could do 240p/60hz on a CRT. To be honest I even assumed that CRT more or less means interlaced for some reason... Edit: ok, I should've clicked the links in the article! This page pretty much completely answers my questions! https://nicole.express/2021/interlace-me-not.html https://nicole.express/2021/interlace-me-not.html
- Tommstein 4y ago
  Man, you used to be able to write X modelines to get CRTs to do just about anything you wanted as long as they were physically capable of it. I think it was an ancient version of this guide that I followed many a time to get a new CRT up to . . . let's call it peak performance: https://tldp.org/HOWTO/html_single/XFree86-Video-Timings-HOWTO/ https://tldp.org/HOWTO/html_single/XFree86-Video-Timings-HOW...
  - p1necone 4y ago
    There's actually custom AMD GPU firmware called CRT emudriver for older cards that still had analogue output to push custom modelines to CRTS: http://geedorah.com/eiusdemmodi/forum/viewtopic.php?pid=1009#p1009 http://geedorah.com/eiusdemmodi/forum/viewtopic.php?pid=1009... It's used in the retro gaming community to get hardware accurate video output from emulators.
- richardjam73 4y ago
  That article reminds me of a certain question I had recently. Is it possible to design a crt type video display that doesn't suffer from phospor loss?
- p1necone 4y ago
  For anyone else curious the TLDR is that 240p is really 480i with tweaked timings so that the lines from the two interlaced frames strike the screen in the same place. This is also why a lot of old 240p consoles (NES/Master System through to PS1/N64/Saturn ) look even worse on modern TVs than you would expect them to - the TV tries to deinterlace the signal, but it's not really interlaced. With a 240p aware linedoubler converting your signal to 480p HDMI you can get much better results, and much lower latency.
computronus 4y ago
My favorite project ever in undergraduate was getting these glasses to work with a PC. We got the specs (pun intended) from online resources and a how-to VR book published at the time (mid-90s). My partner designed / assembled the circuit board to interface the glasses to the PC's serial port, and I wrote a display driver that would switch video pages and simultaneously trigger the glasses to flip shutters. The result was 3D on a PC screen. The demo program was a robotic arm simulator that my partner already had on hand, since it could easily render wireframes. The updated simulator rendered two wireframes of Optimus Prime, so with the driver in place, he floated in front of the screen. And, of course, you could rotate him in space, and then hit the space bar to transform him in 3D.
- Melraidin 4y ago
  Was it this book? https://www.goodreads.com/en/book/show/1990755 https://www.goodreads.com/en/book/show/1990755 I hacked up a Powerglove to connect to my PC. Always wanted to get the Sega glasses too but didn't have the resources at the time.
  - computronus 4y ago
    I think it was this one, The Virtual Reality Construction Kit by Gradecki. The cover looks very familiar! https://www.goodreads.com/book/show/3165591-the-virtual-reality-construction-kit https://www.goodreads.com/book/show/3165591-the-virtual-real...
    - Melraidin 4y ago
      Didn't come across that one at the time. Wish I'd tried more to get a homebrew VR setup going. I still have that VR book in my basement. Along with my first computer book, Practical Things To Do With A Microcomputer. Usborne has these online: https://usborne.com/ca_en/books/computer-and-coding-books https://usborne.com/ca_en/books/computer-and-coding-books
Twirrim 4y ago
I don't remember who produced them, but I had a pair of active shutter 3D glasses back in something like 2000, maybe? I think they were Elsa Revelators. All I remember of them was that when they worked they were brilliant, albeit a little dim. Mostly all they did, though, was expose all the shortcuts developers took, particularly with UI elements. Everything in the scene would be wonderful 3D, but the UI elements would be all over the place, distorted, etc. etc.
Asooka 4y ago
Regarding the LCD problem: Don't you simply have to align the signal sent to the glasses with the LCD frames? You don't need the full delay, as the switching is rhythmic, so you only need up to 1 frame, or 1/30th of a second. I imagine it shouldn't be too hard to build an analogue device with a knob to control the delay, after which you just turn it to whatever position shows the appropriate image for each eye.
- toast0 4y ago
  I think you'd need up to 2 frames. Up to 1 frame lets you line up to the vblank more or less, and the 2nd frame lets you pick which eye. Might be able to do it with an adjustment for the delay and a switch to toggle the eyes. Edit: if you happen to have a 3d tv still, it might be possible to tell it you've got frame sequential 3d content and then use its glasses. Possibly.
w-ll 4y ago
So this is how the active Nvidia Gforce glasses work. Most references are scrubbed from their site now, I had a pair and the monitor and they were actually pretty great. I also posted a plea in the thread the other day about dumb tvs [2]. There are passive 3d stuff with bad viewing angles. But I do love my 3d content and dont mind glasses. [1] https://web.archive.org/web/20140325101340/https://www.nvidia.in/object/3d-vision-main-in.html https://web.archive.org/web/20140325101340/https://www.nvidi... [2] https://news.ycombinator.com/item?id=35484594&p=4#35488578 https://news.ycombinator.com/item?id=35484594&p=4#35488578
pazimzadeh 4y ago
Kind of related: most people can generate a stereoscopic image by crossing their eyes https://stereo.gsfc.nasa.gov/gallery/crosseyed.shtml https://stereo.gsfc.nasa.gov/gallery/crosseyed.shtml

129 points by robin_reala 4y ago

efnx 4y ago

I wish there were more sites like Nicole express. Great job with the break down.

One thing I wish is that the parts of the 3d image were also side-by-side instead of (or in addition to) moving. I trained myself to look at these kinds of things cross-eyed so I can see the 3d effect without glasses.

jayd16 4y ago
Even just speeding up the flicker would induce a more 3d effect.

genpfault 4y ago

Not loading for me; archive: https://archive.is/hjChf https://archive.is/hjChf

binarymax 4y ago

I had the (dis)pleasure of using these as a kid. Gave me a wicked headache. But awesome writeup! Reading how they worked I finally understand why I got the headache :)

ChuckNorris89 4y ago
Hey, at least you got to experience the ...puts on shades... Segaverse.
allenu 4y ago
Did you ever try plying them without the glasses? Now that’s a headache! I had a Master System as a kid and was disappointed when I purchased Maze Hunter 3D and brought it home only to find I could not play it without the glasses. No wonder they were discounted. However, I did read in a book that Space Harrier 3D had an Easter egg that allowed you to disable the 3D feature, but you had to get on the high score screen to execute the code. I ended up buying that at a discount. I got quite good at getting through the first level of the game without the 3D glasses.
- nsxwolf 4y ago
  Zaxxon 3D also let you turn off the 3D. Not sure why all the games didn't. There's no good way to play them today without the peripheral and a CRT.
- cholmon 4y ago
  I had a Master System as well, but my glasses broke early on in my ownership, so I played Maze Hunter, Blade Eagle, and Missile Defnce without them. Eventually, I got accustomed to the odd look of everything being slightly doubled. When I finally got a new pair of glasses that worked, the 3D gameplay felt so odd that I preferred playing without them.

ytreyrty 4y ago

will 3D/VR ever really become mainstream? i recently bought a PSVR2, the tech seemed amazing but i had to return it due to horrible motion sickness. we're at almost 30 years of the tech still not being ready for prime time.

edent 4y ago
Not until they overcome the need for the viewer to do something. Moving from mono sound to stereo doesn't require anything of the listener. Going from black and white to colour doesn't require you wear special equipment. But 3D? You have to put on special glasses which you also have to remember to charge. Oh, and you can't look at other things while you're using them. There were some passive 3D displays (the Nintendo 3DS and a few early Android phones) but they required the user to stay in exactly the right position, or the illusion was destroyed. So you couldn't easily share the experience with a friend. Until we have TVs which can shoot lasers directly into our eyeballs, I think the barrier to entry is too high.
- sudosysgen 4y ago
  These kinds of VR headsets don't need to be charged (they are wired) and you can press a button to see the real world through the cameras.
  - edent 4y ago
    So now I need to be physically tethered to my seat? Do I press the button on the left or the right? Is it one tap to see the real world or two?
    - sudosysgen 4y ago
      The cable is long enough that your room will run out before you run out of cable, so no need to be tethered to your seat. Generally to pass through the real world you'd do something like simulatenously press two easily accessible buttons on your tracked controller. It is really very easy and I use it often.

mardifoufs 4y ago

>240p is fake and a lie, but close enough for us I want to know more :) and my googling skills are failling me. But I didn't even realize you could do 240p/60hz on a CRT. To be honest I even assumed that CRT more or less means interlaced for some reason... Edit: ok, I should've clicked the links in the article! This page pretty much completely answers my questions! https://nicole.express/2021/interlace-me-not.html https://nicole.express/2021/interlace-me-not.html

Tommstein 4y ago
Man, you used to be able to write X modelines to get CRTs to do just about anything you wanted as long as they were physically capable of it. I think it was an ancient version of this guide that I followed many a time to get a new CRT up to . . . let's call it peak performance: https://tldp.org/HOWTO/html_single/XFree86-Video-Timings-HOWTO/ https://tldp.org/HOWTO/html_single/XFree86-Video-Timings-HOW...
- p1necone 4y ago
  There's actually custom AMD GPU firmware called CRT emudriver for older cards that still had analogue output to push custom modelines to CRTS: http://geedorah.com/eiusdemmodi/forum/viewtopic.php?pid=1009#p1009 http://geedorah.com/eiusdemmodi/forum/viewtopic.php?pid=1009... It's used in the retro gaming community to get hardware accurate video output from emulators.
richardjam73 4y ago
That article reminds me of a certain question I had recently. Is it possible to design a crt type video display that doesn't suffer from phospor loss?
p1necone 4y ago
For anyone else curious the TLDR is that 240p is really 480i with tweaked timings so that the lines from the two interlaced frames strike the screen in the same place. This is also why a lot of old 240p consoles (NES/Master System through to PS1/N64/Saturn ) look even worse on modern TVs than you would expect them to - the TV tries to deinterlace the signal, but it's not really interlaced. With a 240p aware linedoubler converting your signal to 480p HDMI you can get much better results, and much lower latency.

computronus 4y ago

My favorite project ever in undergraduate was getting these glasses to work with a PC. We got the specs (pun intended) from online resources and a how-to VR book published at the time (mid-90s). My partner designed / assembled the circuit board to interface the glasses to the PC's serial port, and I wrote a display driver that would switch video pages and simultaneously trigger the glasses to flip shutters. The result was 3D on a PC screen. The demo program was a robotic arm simulator that my partner already had on hand, since it could easily render wireframes. The updated simulator rendered two wireframes of Optimus Prime, so with the driver in place, he floated in front of the screen. And, of course, you could rotate him in space, and then hit the space bar to transform him in 3D.

Melraidin 4y ago
Was it this book? https://www.goodreads.com/en/book/show/1990755 https://www.goodreads.com/en/book/show/1990755 I hacked up a Powerglove to connect to my PC. Always wanted to get the Sega glasses too but didn't have the resources at the time.
- computronus 4y ago
  I think it was this one, The Virtual Reality Construction Kit by Gradecki. The cover looks very familiar! https://www.goodreads.com/book/show/3165591-the-virtual-reality-construction-kit https://www.goodreads.com/book/show/3165591-the-virtual-real...
  - Melraidin 4y ago
    Didn't come across that one at the time. Wish I'd tried more to get a homebrew VR setup going. I still have that VR book in my basement. Along with my first computer book, Practical Things To Do With A Microcomputer. Usborne has these online: https://usborne.com/ca_en/books/computer-and-coding-books https://usborne.com/ca_en/books/computer-and-coding-books

Twirrim 4y ago

I don't remember who produced them, but I had a pair of active shutter 3D glasses back in something like 2000, maybe? I think they were Elsa Revelators. All I remember of them was that when they worked they were brilliant, albeit a little dim. Mostly all they did, though, was expose all the shortcuts developers took, particularly with UI elements. Everything in the scene would be wonderful 3D, but the UI elements would be all over the place, distorted, etc. etc.

Asooka 4y ago

Regarding the LCD problem: Don't you simply have to align the signal sent to the glasses with the LCD frames? You don't need the full delay, as the switching is rhythmic, so you only need up to 1 frame, or 1/30th of a second. I imagine it shouldn't be too hard to build an analogue device with a knob to control the delay, after which you just turn it to whatever position shows the appropriate image for each eye.

toast0 4y ago
I think you'd need up to 2 frames. Up to 1 frame lets you line up to the vblank more or less, and the 2nd frame lets you pick which eye. Might be able to do it with an adjustment for the delay and a switch to toggle the eyes. Edit: if you happen to have a 3d tv still, it might be possible to tell it you've got frame sequential 3d content and then use its glasses. Possibly.

w-ll 4y ago

So this is how the active Nvidia Gforce glasses work. Most references are scrubbed from their site now, I had a pair and the monitor and they were actually pretty great. I also posted a plea in the thread the other day about dumb tvs [2]. There are passive 3d stuff with bad viewing angles. But I do love my 3d content and dont mind glasses. [1] https://web.archive.org/web/20140325101340/https://www.nvidia.in/object/3d-vision-main-in.html https://web.archive.org/web/20140325101340/https://www.nvidi... [2] https://news.ycombinator.com/item?id=35484594&p=4#35488578 https://news.ycombinator.com/item?id=35484594&p=4#35488578

pazimzadeh 4y ago

Kind of related: most people can generate a stereoscopic image by crossing their eyes https://stereo.gsfc.nasa.gov/gallery/crosseyed.shtml https://stereo.gsfc.nasa.gov/gallery/crosseyed.shtml