alt.hn

3/19/2026 at 3:55:03 AM

Conway's Game of Life, in real life

 https://lcamtuf.substack.com/p/conways-game-of-life-in-real-life

by surprisetalk

3/19/2026 at 1:01:08 PM

This is fantastic.

I happen to own a physical pong table. Everyone loves it. [0] There is something magical about material and only-does-one-thing instantiations of digital things.

——

I am really looking forward to a flat table top screen consisting of millions of magnetically-controlled vertical-extruding rod pixels, with actual color controlled pixels along their length. For an amazing table display/extrusion of D&D dungeons and terrain, for miniatures.

A little sensor ability, and when the extrusion "scrolls" laterally, it could create little lips that move the miniatures too, so they stay "in place". And move NPCs around at the DMs direction. Now turn of the room lights, and use the light pixels not just for color, but for lighting effects like wall lamps flickering, add spooky position-distributed sounds...

That has to be coming soon, right?

Some part of me wants to describe it Claude, iterate, and say "Now polish that design, economically optimize the parts, link in the supply chain, and ship me the first review unit." That has to be coming soon, right?

The lines separating planes of reality, they are a blurring, quickly.

——

[0] https://www.youtube.com/watch?v=84Ymt9BAq5s

by Nevermark

3/19/2026 at 1:59:18 PM

And optimize for repair when one of the thousands of actuators gets stuck or burns out…

Here’s a thought, though: you’ve seen the sand table + kinect projection mapping demo? What about that, plus a two-axis moving magnet sand mandala marble drawing table? The actuator could draw the path /sculpt the terrain, then release the marble and grab the figurines?

by relaxing

3/19/2026 at 3:31:11 PM

Thanks. I had not seen that. It is definitely the poor mans software controlled physical reality I am looking for! :)

Yeah, that would provide a much richer environment for table top role play games. And allow for telepresence meet ups.

by Nevermark

3/19/2026 at 5:16:36 PM

the trick it to be able to actuate the rods without placing a linear actuator on every one, but it's a complicated problem. Magnetism? hydraulic shafts fed and drained by a series of gates making a matrix? acoustic levitation?

I'm reminded of the old BERG London pixel track display that used a little cart with a vertical array of solenoids that would travel the length of the display flipping each individual pixel on an off physically. https://www.designboom.com/technology/pixel-track-berg-cloud... It's on my list of'next time i'm unemployed' projects to pick up and open source a design for.

by sleepybrett

3/19/2026 at 7:47:16 AM

> I figured out what would be a reasonable amount to spend on the project and then multiplied that by 10.

I like the way you think.

by exolab

3/19/2026 at 11:20:21 AM

Jeff Atwood has a great quote:

"I needed to replace 18 lightbulbs in my chandelier. Turns out 18 times any number is a lot. In cash"

by alexpotato

3/19/2026 at 11:43:51 AM

A much cheaper way might have been to buy a couple of Novation Launchpads. 8x8 full RGB tactile buttons for 90€, MIDI-controllable. Four of those next to another for 16x16 at 360€ plus a little bit for cables and controller comes out at 1/3 the price

by kangalioo

3/19/2026 at 1:34:17 PM

It would be larger (even with the mini), you’d have gaps between the four, and also the four middle buttons in each part have their corners clipped.

But you can get illuminated buttons for less money: https://www.ebay.com/itm/173922115935

by layer8

3/19/2026 at 1:40:20 PM

Looking at teardown images of the launchpad pcb, it might be possible to shave down the ground plane on the two non-button sides enough that you could mate them up with no bezel interfering.

Re: illuminated tact’s: Old launchpads go for $25 - $30 on ebay, and you don’t have to purchase your own control and power components…

by relaxing

3/19/2026 at 2:01:18 PM

The size and button shape concerns would remain.

by layer8

3/19/2026 at 5:43:52 PM

> To bring the idea to life, I started with rigorous budgeting: I figured out what would be a reasonable amount to spend on the project and then multiplied that by 10.

Lol, this is the way to do hobbies

by bawolff

3/19/2026 at 9:54:45 AM

Totally off-topic, and I may be wrong, but I immediately loved the non-LLM writing-style and felt glued to the content just through the writing alone. It's getting rare.

by mittermayr

3/19/2026 at 10:41:50 AM

I have not felt that it was becoming rare. Certainly on platforms like YouTube you can see automated processes cranking blandness at scale. I haven't found it encroaching on the topics that interest me like toy electronic projects, how some ancient game rendered its Sprites, colour space analysis, or a compiler that fits in a tweet,

I'm sure there are an abundant source of 'How I hustled a thumpawangy into $1000 a month in subscriptions" written by AI, but I doubt I could perceive a loss in that compared to the ones we had before.

by Lerc

3/19/2026 at 3:23:58 PM

Do you have a link? Been looking to switch thumpawangy vendors.

by fwipsy

3/19/2026 at 10:32:20 AM

Personally, I can barely stomach reading LLM writing. I find myself closing lots of articles after a sentence or two. I wonder how this plays out longer-term regarding engagement.

by tmountain

3/19/2026 at 1:08:49 PM

In probably another year or two I expect the metrics will show that it is a positive turn off. Unfortunately we're on the cutting edge of this particular movement and there's still a lot more "value" to be "extracted" from the general public before they all get wise to it too.

The next problem we'll face after that, with the 1-2 years newer AIs of the time, is that the default LLM voice is just a particular affectation created by the training, not "the voice of LLMs" or anything. It's trivial to kick them into a different style. I just used AI to do some architecture design documents this week, and prompted it to first look at about 1-2k words that I wrote myself all organically for the style. The good news is the resulting documents almost, but admittedly, not quite entirely, lack that LLM style. They're still prone to more bullet lists than I use directly; then again, in this context they were fairly appropriate, so I'm not too triggered by the result.

The bad news is, that's all it takes to make AI writing that isn't in that default tone. It's not that hard. Students cheating on essays have already figured it out, the spammers really can't be that far behind. Probably more stuff than we realize is already AI output, it's just the stragglers and those who don't really care (which I imagine is a lot of spammers, after all) who are still failing to tweak the style. They'll catch up as soon as engagement falls off.

by jerf

3/19/2026 at 3:26:46 PM

I think HN readers are the leading edge of the technology literate. Might take longer than you think for the general public to start noticing "AI voice."

by fwipsy

3/19/2026 at 10:28:28 AM

lcamtuf is doing that for decades!

by zytek

3/19/2026 at 12:30:55 PM

[flagged]

by ctdinjeu3

3/19/2026 at 8:07:30 AM

I saw one in a computer museum in Switzerland. It was a much larger field, it was just large orange LEDs (or were they tubes?), but it also cycled between a dozen of different cell automata games. Something about being able to see individual "pixels" made it really mesmerizing.

by eps

3/19/2026 at 2:22:33 PM

Wow, in switches alone this would cost me $1200! Which actually isn't that bad for a one off-like this with easily available components - I've seen worse. You can of course take your chances with Aliexpress Specials but be warned: some of those cheap switches are cheap switches (sometimes, they're barely even switches). And you won't be getting them inside of 2 weeks.

I think I would have tried mechanical keyboarding switches that can take an LED and a clear keycap. Not really the same effect, but you could probably have gotten out to 24x24 for the same price.

by alnwlsn

3/19/2026 at 1:27:48 PM

Technology Will Save Us, from a brighter past, produced the Arcade Coder as their swan song. It had 12×12 tactile buttons with color leds inside, a companion app to program it with scratch like code blocks, and interactive tutorials. It's ESP32 based. There's an effort to continue it's life, ast the app was on the app store for a brief time. https://github.com/padraigfl/twsu-arcade-coder-esp32

by kanapala

3/19/2026 at 8:38:50 AM

When I was a teenager, I read a book about assembly language for the commodore and implemented the game of life in a really simple way. I just used the text screen. To switch on a cell, I would put an asterisk ('*') in it. Then I could run my machine code program and it would evolve according to the rules of the game of life.

by cjfd

3/19/2026 at 9:06:36 AM

And who didn't do that! :)

You could also 4x the resolution by using half- and quarter-block characters from the top half of the ASCII table (or it'd be the PETSCII one i C64 case).

by abcd_f

3/19/2026 at 10:33:28 AM

> And who didn't do that! :)

Exactly. It's even how I taught myself extremely basic Pascal -- getting my BASIC Life program running in Pascal. With asterisks.

A taught a friend at uni, who was a much better programmer than me, how the algorithm worked. He did a pixel-by-pixel version in machine code, but it was a bit slow on a ZX Spectrum.

So he did exactly the quarter-character-cell version you describe. I wrote the editor in BASIC, and he wrote a machine-code routine that kicked in when told and ran the generations. For extra fun he emitted some of the intermediate state to the border, so the border flashed stripes of colour as it calculated, so you could see it "thinking". Handy for static patterns -- you could see it hadn't crashed.

I've been considering doing a quarter-cell Mandelbrot for about 30Y now. Never got round to it yet.

by lproven

3/19/2026 at 1:13:51 PM

The answer to a lot of "wow, how did the 8-bit machine pull that off? it seems like that would eat a lot of RAM" is that the framebuffer is the data storage. You were literally looking at the primary data store itself, because when a full-resolution framebuffer was 1/4th your addressable RAM (and slightly more than that for your actual RAM since you couldn't ever quite use all 64KB no matter how you mapped it), you need to get the most bang for the buck out of that RAM usage as you can.

by jerf

3/19/2026 at 7:18:05 PM

Ha, I remember doing this with my Apple //. I forget what I was doing, but realized if I could set a pixel and later get what color was drawn at that location I could use it as a big array. Didn't know about peek/poke yet. One of those core "computers are magic" memories.

by tempaccount5050

3/19/2026 at 2:33:14 PM

When I got into retrocomputing a few years ago, I also did this. Works great with TRS-80 semigraphic characters. First, I wrote it in C with a Z80 c compiler. The, I wrote it again in assembly and it was much faster! Amazing!

by alnwlsn

3/19/2026 at 1:48:10 PM

This would be something neat to do with a core memory array, just like this but bigger:

https://www.core64.io/

by satiated_grue

3/19/2026 at 8:25:47 AM

A thousand bucks for 17x17 touchscreen. Add a painting frame, hang it on the wall, and you made yourself amazing art for cheap.

by mastermedo

3/19/2026 at 11:57:38 AM

Something like those switches might be made very cheaply with a 3D printer, possibly a laser cutter, some transparent or semitransparent acrylic sheet, tactile switches and some LEDs. I designed a cheapo replacement for $50 tellite switches and got the price down to about $0.60 Not quite the same, as these are a lot bigger, and getting things down to the desired size might be troublesome. Anyway, here's a little video of my fake cheapo tellite switches: https://www.youtube.com/watch?v=LaenrgPVCjc

by smcameron

3/19/2026 at 11:42:43 AM

I wonder if going for keyboard switches with RGB could bring the price down, if you then either print the keycaps yourself, our use a 3d printing service. 23 Cherry MX switches cost 20€, that‘s roughly 260€ for a 17x17 matrix.

by MrGilbert

3/19/2026 at 12:00:54 PM

Should be doable to implement GoL on an ortholinear RGB keyboard using QMK

by waterproof

3/19/2026 at 1:26:31 PM

I mean - that sounds like an awesome project in itself!

by MrGilbert

3/19/2026 at 9:09:44 AM

I love this and would love to see it on a wall at our office or something like that. Maybe there's smaller/cheaper led/switches that would work in a handheld version.

by Cthulhu_

3/19/2026 at 7:43:45 AM

Très cool.

A grid of capacitive touch sensors could be printed directly on the pcb, bringing down costs by a degree of magnitude. Real switches are much more satisfying though.

by slow_typist

3/19/2026 at 7:57:35 AM

I want to do a game like lights out. I'm thinking in 3d printing transparent caps and using dirt chip pcb switches and standard leds. The cost must be also down to 30 cts. Would be like a middle ground.

by f1shy

3/19/2026 at 5:38:51 PM

> Can it be made for less?

Would you be able to use the LEDs as light sensors and eliminate the switch component entirely? Maybe a tubular shield over each LED so it doesn't interact with others around it then covering it with your finger could be read as toggling the state?

by Melraidin

3/19/2026 at 6:57:59 PM

The rest of your hand is not transparent and will cover a lot of other buttons while you’re only trying to push one.

by egypturnash

3/19/2026 at 9:18:32 PM

I'd assume you could detect a difference between a completely/nearly completely covered LED shield and one with a large gap between your hand at the top of the shield.

by Melraidin

3/19/2026 at 3:13:47 PM

Someone's senior project was an EEPROM based life in discrete logic and a bunch of LEDs. There was no CPU; the ROM served as a state machine. I wish I knew more about it now; I'm not sure how it latched state.

by imglorp

3/19/2026 at 6:56:58 AM

I wonder is there a version GoL where every bit on a computer-display or LCD TV is one cell? How does it look?

by galaxyLogic

3/19/2026 at 3:42:35 PM

I did something like this: a 64x64 (4K) display of GoL (among other things) using addressable pixels. Alas, I only took one video when the display was working and it wasn't fully cleaned up: https://photos.app.goo.gl/WUmVgBVVi6rXDqSB7

by dekhn

3/19/2026 at 7:32:57 AM

Do you mean every pixel or every sub-pixel? Sub-pixel is interesting because the geometry of the grid isn't going to be the same from one screen to the other. It might also look compressed horizontally.

by alex_duf

3/19/2026 at 7:44:35 AM

[dead]

by vscode-rest

3/19/2026 at 2:34:26 PM

How many bits per pixel are you assuming, and are you imagining the red pixels are vertical neighbors with corresponding red pixels above and below, etc.?

Should be easy to do on my phone: https://itch.io/post/15723528

by akkartik

3/19/2026 at 5:24:19 PM

Good point to explore

by galaxyLogic

3/19/2026 at 7:21:05 PM

At 8 bpp the effect is only colors moving vertically, up and down. After a while digging into it I realize why: most colors are too dark to be visible, we only see the most significant bits in each channel. And when those bits influence left or right the consequences are not visible.

Maybe I should try 2bpp. Or some HSL where I can clamp L.

Edit: Oh yes, it's interesting at 2bpp!

by akkartik

3/19/2026 at 8:10:55 AM

Conversely, it'd be cool to play it on an large empty office building.

One window = one pixel.

by eps

3/19/2026 at 5:26:02 PM

Right but what if every window was an outward pointing LCD screen each having their own node-per-pixel GoL !:_)

by galaxyLogic

3/19/2026 at 10:28:36 AM

Nicely done! Scale matters. If you make something big enough relative to its expected size, it will impress and captivate, even if it's simple. General observation, not that the construction here was by any means simple.

by possiblydrunk

3/19/2026 at 3:49:56 PM

Damn around $900 just for the switches, I feel it, little project costing a lot but it's fun

In my case a $300 camera that produces worse photos than an old flagship $50 camera from eBay

by ge96

3/19/2026 at 6:54:21 AM

I've always wanted something like this board, buttons which can light up (preferably a few colours), to use to make games. Anyone ever found such a board which is hackable / programmable?

by CJefferson

3/19/2026 at 7:34:46 AM

Novation Launchpad used to be exactly that: you send MIDI CC messages with proper values and you can light up the grid (with different colors).

Did that a few years back, i guess this might still be possible

by rmnclmnt

3/19/2026 at 8:14:12 AM

> used to be

Looks like they are still around? https://novationmusic.com/launchpad

Also seems to be in stock locally.

The device that I think popularized that design (citation needed) was the Monome (https://monome.org/) that looks like it is also still around and it has (always had?) some kind of open source license (https://github.com/monome).

by 1313ed01

3/19/2026 at 4:00:24 PM

Thanks for the heads up! I have been out of this loop for quite a while, glad to see it's still there!

Yes Monome was this initial inspiration then followed by many, but it was way more expensive and niche IIRC

by rmnclmnt

3/19/2026 at 6:45:50 PM

Aliexpress has a lot of cheap "smart gomoku board" now, they are cheap rgb-lighted membrane button grids O(13x13) with firmware playing games like Go, Reversi etc. (https://he.aliexpress.com/item/1005010089221164.html, https://he.aliexpress.com/item/1005011840606955.html ...). These proved to be surprisingly fun with children, the tactile interface is neat, and they're a good middle ground that helps learn the rules of games (has 1-on-1 modes + solo against several levels of "AI") but not as brain-rot distracting like a tablet.

I haven't tried reverse-engineering one yet, I hope at least some of these are hackable? Conway's life would certainly be one fun use, but custom games are totally something I'd want to make too!

Are these actually membrane or are there some switches there? I assume membrane, if only based on the dirt-cheap price. Anyway in combination with lighting up + sound the feedback feels immersive enough, it's definitely more fun than poking a tablet.

by cben

3/19/2026 at 12:54:50 PM

Lovely project indeed. If you want to build your own: I found a whole bunch of much cheaper illuminated switches on AliExpress within minutes.

by Tepix

3/19/2026 at 10:35:56 AM

This is fantastic, but there's no way I am taking the time to build one, and the cost is a little frightening...

by lproven

3/19/2026 at 6:20:58 AM

I don't want to build this or pay for it, but I really want to mess with it for an hour.

by fwipsy

3/19/2026 at 9:46:07 AM

You need a science museum!

by nsnzjznzbx

3/19/2026 at 11:03:13 AM

I bet that the author would really get a kick out of the T2 Tile Project.

by rojoroboto

3/19/2026 at 8:03:50 AM

That's not a "physical" version of game of life -- that's a digital version, like every version, but with bigger pixels.

by self_awareness

3/19/2026 at 8:39:42 AM

I think "physical" refers to the fact that you initialize the state by pressing physical buttons. That's quite accurate.

by gspr

3/19/2026 at 10:01:12 PM

Well keyboard also has physical buttons. And mouse.

by self_awareness

3/19/2026 at 1:18:20 PM

Great idea and execution. I like your thinking.

by mvrckhckr

3/19/2026 at 11:44:56 AM

how is this real life more than a monitor, its just bigger pixels. i was expecting programmable live cells or something mechanical

by jFriedensreich

3/19/2026 at 11:55:58 AM

Check out the video - you can draw on the game by pressing the switches.

by waterproof

3/19/2026 at 8:40:56 AM

It is beautiful

by mkirsten

3/19/2026 at 4:03:57 PM

Good old analog computers

by mohamedkoubaa

3/19/2026 at 1:26:49 PM

This isn't what this is about, but I wonder if anyone has created a fully mechanized version of Conway's Game of Life. The fact that you only have to follow 4 rules, and each cell only needs to observe its neighbors to follow those rules, makes me wonder if it's possible to track these things mechanically. I unfortunately don't know enough about mechanical engineering to do such a thing.

by alexb_

3/19/2026 at 7:08:27 PM

It's not edge to edge, though maybe if you built your own silicon overlay you could make it edge to edge.. but adafruit sells these tileable pcbs and silicon overlays with capacitive buttons: https://www.adafruit.com/product/3954

by sleepybrett

3/19/2026 at 4:29:26 PM

In the seatac airport there used to be a big 'life wall' they did their switches w/ capacitive metal disks

by sleepybrett

3/19/2026 at 9:13:57 AM

Would be interesting to do this with people and observe the inevitable mistakes they make.

Now that would be simulating life witg life.

by Traubenfuchs

3/19/2026 at 9:58:08 AM

Well, people can die if they have too many or too little of neighbors, but they can't be summoned from a thin air if they have just enough neighbors. Hard to simulate life with people. Though if you are ready for a simulation step of 20 years or so... But it still may not work, because you need people of two opposing sexes and compatible genders near the empty sell to fill it. In Game of Life all cells are hermaphrodites.

But I agree mistakes might be fun to watch.

by ordu

3/19/2026 at 1:25:27 PM

Eh. I thought they had somehow created a physical realization of Conway's Game of Life.

by meindnoch

3/19/2026 at 2:02:00 PM

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by irenetusuq

3/19/2026 at 2:48:41 PM

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by Lliora

3/19/2026 at 12:42:18 PM

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by zuiko_39182

3/19/2026 at 9:16:54 AM

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by gethwhunter34

3/19/2026 at 3:11:56 PM

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by Iamkkdasari74

3/19/2026 at 8:36:21 AM

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by shawoodle65

3/19/2026 at 4:57:35 PM

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by andysalmela34