Search found 463 matches

by pcallahan
Today, 1:53 pm
Forum: The Sandbox
Topic: Squiggles
Replies: 7
Views: 212

Re: Squiggles

Simple connected blobs without holes can be applied to recognize still life neighborhoods in CGOL. This illustrates the idea at a schematic level, but you could just as easily use thicker lines to make blobs. Use an approach like the petal tiles to collect neighbor counts, but instead of representin...
by pcallahan
February 14th, 2020, 11:27 am
Forum: Other Cellular Automata
Topic: Any serious survey of constructions in Margolus Critters?
Replies: 39
Views: 6802

Re: Any serious survey of constructions in Margolus Critters?

This probably isn't worth posting but eh, whatever. I found this silly thing the other night while procrastinating. It's a clunky 90° reflector that gets its shape/phase changed every time a glider passes (a whole cycle is 8 gliders). Input must be of the form 8n + 24 where: n >= 0. x = 53, y = 35,...
by pcallahan
February 13th, 2020, 12:49 pm
Forum: The Sandbox
Topic: Squiggles
Replies: 7
Views: 212

Re: Squiggles

Interesting. Here's a not well thought out game idea-- Use two or three colors for the black blobs. If I calculate correctly, there would be 90 tiles with two colors, 300 with three, and 1400 with four. Then the object of a two person (or more?) game would be to build a complete four tile pattern, ...
by pcallahan
February 12th, 2020, 4:49 pm
Forum: The Sandbox
Topic: Squiggles
Replies: 7
Views: 212

Re: Squiggles

I just realized that the simple connected "blobs" are actually spanning trees of the boundary nodes (a node is just the interval of black space on each boundary). This is true for the corner tiles above as well as the original tiles. This explains some of the requirements for connectivity. If there ...
by pcallahan
February 11th, 2020, 8:00 pm
Forum: The Sandbox
Topic: Thread for Non-CA Academic Questions
Replies: 315
Views: 76587

Re: Thread for Non-CA Academic Questions

What's the general formula for the area of a regular n-gon with side length 1? I know, not very academic question You can look that up pretty easily (I checked). If you want to work it out yourself, think of the n-gon as consisting of n isosceles triangles with a base length 1 and angle 360°/n. Div...
by pcallahan
February 9th, 2020, 3:41 pm
Forum: The Sandbox
Topic: Squiggles
Replies: 7
Views: 212

Re: Squiggles

Here's one I've only sketched out, but what if we connect corners instead of sides with non-crossing arcs. Then which corner placements result in single closed curves without holes. For this size, there are 14 possible corner tiles. And here are some examples of combining them. Screen Shot 2020-02-0...
by pcallahan
February 8th, 2020, 1:46 pm
Forum: The Sandbox
Topic: Low-tech universal computing
Replies: 15
Views: 736

Re: Low-tech universal computing

Sorry for non-constructive comments, but I wish I had a set of those tiles. Do you have a printer? All my physical tiles so far are done with an inkjet printer, scrap cardboard (like a cereal box), glue and scissors. It limits me a bit (though I have done triangles and hexagons besides squares usin...
by pcallahan
February 8th, 2020, 12:32 pm
Forum: The Sandbox
Topic: Squiggles
Replies: 7
Views: 212

Re: Squiggles

Sure like tiling, don’t you. You noticed! This actually looks pretty good, if I had these in real life I would start matching them together to see what they would look like. Well, if you have a printer, these ones are sized for printing and cutting. I haven't done it myself with these, at least not...
by pcallahan
February 7th, 2020, 10:06 pm
Forum: The Sandbox
Topic: Squiggles
Replies: 7
Views: 212

Squiggles

The idea is to start with tiles based on matching points like parentheses. The points along the bottom of each tile are connected with circular arcs. E.g., ()(()) would connect positions 0 and 1, 2 and 5, 3 and 4. When you place these tiles together, you may get one or more closed curves. Which ones...
by pcallahan
February 6th, 2020, 3:34 pm
Forum: The Sandbox
Topic: cellular automata according to Max Planck
Replies: 189
Views: 2959

Re: cellular automata according to Max Planck

Moosey wrote:
February 6th, 2020, 7:48 am
otismo wrote:
February 6th, 2020, 1:07 am
maybe some of you Max Planck types could make this a real racetrack...
Then you're out of luck; our only "Max Planck type" isn't known for constructing patterns
And where has our Plonkus Maximus gone? I was starting to think he was getting the hang of how to post here, at least in Sandbox.
by pcallahan
February 5th, 2020, 5:58 pm
Forum: The Sandbox
Topic: Above user in a nutshell
Replies: 656
Views: 65760

Re: Above user in a nutshell

"Help! I'm in a nutshell! How did I get into this bloody great big nutshell? What kind of shell has a nut like this?" (except substitute Moosey for Austin Powers.)

Note that this will work for any "above user" thus proving the general theorem.
by pcallahan
February 4th, 2020, 2:33 pm
Forum: The Sandbox
Topic: Random posts
Replies: 3703
Views: 429757

Re: Random posts

The six Moore neighborhood tiles... "You know, for kids!" blocktiles.png It doesn't look good or anything and I'm a kid. All right then, a minimalist approach. And a new pitch*: "It's very grown up!" (Peppa Pig) Screen Shot 2020-02-04 at 10.30.22 AM.png Just wait. After I build the phalanx with the...
by pcallahan
February 4th, 2020, 1:30 pm
Forum: General Discussion
Topic: Tiling with placement rules for still life and p2 oscillators
Replies: 2
Views: 221

Re: Tiling with placement rules for still life and p2 oscillators

This is really just a slight tweak on the first split-dot approach (update 4 in this post: https://conwaylife.com/forums/viewtopic.php?f=7&t=2188&start=100#p87584), though somehow I was most of the way done before realizing it. I think it makes for a better visualization. The main idea is to use cir...
by pcallahan
February 1st, 2020, 2:11 pm
Forum: The Sandbox
Topic: Random posts
Replies: 3703
Views: 429757

Re: Random posts

JP21 wrote:
January 31st, 2020, 11:46 pm
It doesn't look good or anything and I'm a kid.
I'll need to work on a better pitch. :|
by pcallahan
February 1st, 2020, 3:00 am
Forum: General Discussion
Topic: Realizing still life constraints as a planar tiling
Replies: 110
Views: 43708

Re: Realizing still life constraints as a planar tiling

I feel as if still life violations would jump out at me, but I should probably test that with real non-still-life patterns. For some additional comparisons, here's a glider and blinker. I think the violations mostly jump out, but I might have missed the cell birth on the glider if I wasn't looking ...
by pcallahan
January 31st, 2020, 10:17 pm
Forum: The Sandbox
Topic: Random posts
Replies: 3703
Views: 429757

Re: Random posts

The six Moore neighborhood tiles... "You know, for kids!"
blocktiles.png
blocktiles.png (12.99 KiB) Viewed 129 times
by pcallahan
January 31st, 2020, 7:18 pm
Forum: General Discussion
Topic: Realizing still life constraints as a planar tiling
Replies: 110
Views: 43708

Re: Realizing still life constraints as a planar tiling

Back before computers, I did use up lots of graph paper (and erasers were cheaper than new paper). Still have some of that around here somewhere. At some point it did become unnecessary to count neighbors, just recognize the patterns. I had an early TRS-80 computer before I ever heard of Life, so I...
by pcallahan
January 31st, 2020, 10:40 am
Forum: The Sandbox
Topic: Thread for Non-CA Academic Questions
Replies: 315
Views: 76587

Re: Thread for Non-CA Academic Questions

Suppose we make a domino tiling like this and we swap each adjacent pair. Symbolically, if you did it with all horizontal dominoes, you get this series of swaps: a↔b, c↔d, e↔f, g↔h, i↔j, k↔l, m↔n, o↔p. That's one possible permutation of the values, but each domino tiling defines a different one. So...
by pcallahan
January 30th, 2020, 10:22 pm
Forum: The Sandbox
Topic: Thread for Non-CA Academic Questions
Replies: 315
Views: 76587

Re: Thread for Non-CA Academic Questions

I'm not sure this is academic, but it's non-CA, at least directly. I'll post it as a puzzle in case someone else wants to think of a solution. We have a 4x4 grid of values (or you could generalize it, but I am interested in n=4). Assigning variable names, it looks like this: a b c d e f g h i j k l ...
by pcallahan
January 30th, 2020, 7:26 pm
Forum: General Discussion
Topic: Realizing still life constraints as a planar tiling
Replies: 110
Views: 43708

Re: Realizing still life constraints as a planar tiling

I can see how this will produce all valid patterns and only valid patterns, but as it appears to be rules-agnostic, it won't exclude non-still-lifes. It is pretty, though. On the other hand, if you only want to show valid patterns, you could just use the first two tiles, and the we're back to how L...
by pcallahan
January 30th, 2020, 4:07 pm
Forum: The Sandbox
Topic: cellular automata according to Max Planck
Replies: 189
Views: 2959

Re: cellular automata according to Max Planck

Not quite true: the ZX81 can be programmed to simulate life at plenty of generations per second. Based on my knowledge of z80 assembly, I'd guess that you could easily get 100gps - and when you have a 64x48 graphics mode, that's more than enough. Agreed, though my early experience was with a TRS-80...
by pcallahan
January 30th, 2020, 2:44 pm
Forum: The Sandbox
Topic: Low-tech universal computing
Replies: 15
Views: 736

Re: Low-tech universal computing

Here's a 6-tile set that pulls the complete Moore neighborhood into the middles of cells. Without any placement rules except matching boundaries, you can use it as a visual aid for analyzing the next step of any 2-state Moore neighborhood CA.
Screen Shot 2020-01-30 at 10.20.03 AM.png
Screen Shot 2020-01-30 at 10.20.03 AM.png (37.5 KiB) Viewed 195 times
by pcallahan
January 30th, 2020, 1:34 pm
Forum: The Sandbox
Topic: Random posts
Replies: 3703
Views: 429757

Re: Random posts

How to kill time when running searches? Watch live hospital constructions online! 火神山医院建设 雷神山医院建设 All Hail Wuhan! In the US it takes (rough guess here) anywhere from 5-10 years to build a new hospital, or more likely a new wing of an existing hospital. Much of that is stuck in funding and permit is...
by pcallahan
January 30th, 2020, 12:05 pm
Forum: General Discussion
Topic: Realizing still life constraints as a planar tiling
Replies: 110
Views: 43708

Re: Realizing still life constraints as a planar tiling

(skipping over the recent posting) I like the split dots better. With the petals, it isn't entirely obvious which quadrants are contributing. The split dots show that orthogonally, it takes two tiles to contribute, but only one diagonally. Here's another variation, and maybe it's the right one for ...
by pcallahan
January 29th, 2020, 7:51 pm
Forum: The Sandbox
Topic: cellular automata according to Max Planck
Replies: 189
Views: 2959

Re: cellular automata according to Max Planck

we should all care about climate change . . . we should learn to deal with it by having appropriate clothing..... With all due respect, I'm pretty sure that telling people to "just adapt to the climate" qualifies as not caring about climate change. I agree Well, I still like to call it global warmi...