Turtletoy

[jncraton]

If you like this project, you may be interested in a similar project that I did a while back using using the turtle interpretation of grammars to represent connections between LEGO bricks:

https://github.com/jncraton/connectiongrammar

The "API" is admittedly quite poor currently, as I just quickly hacked this together on top of NLTK, but I was able to put together some fun results.

[YeGoblynQueenne]

That's a really cool one. Do you know of any attempts to learn a connection gramar, instead of creating it by hand?

[carapace]

That is really cool!

[rudolfwinestock]

This reminds me of a story of how Logo was implemented on 8-bit microcomputers.

Leigh Klotz was the man who ported MIT Logo to the Apple ][ and then the Commodore 64. According to him “The Commodore 64 CPU 6510 has a bidirectional parallel port at location 0 and 1, taking up 2 of the 256 "page zero" locations, which are the only ones you can indirect through. When I ported MIT Logo from the Apple II, there were lots of places that dereferenced nil without checking, and those caused crashes. Commodore gave me a chip they fabbed in qty 12 yield that brought out the I/D decide status as a pin, and we used a Nicolet-Paratronica logic analyzer to feed the address and data bus to a Pet running a BASIC disassembler. I could then set a breakpoint in-circuit to see the 256 instructions prior to or after the errant memory access, so I could go put on guard code...”

I got it from Jamie Zawinski's weblog. Be forewarned. Following the link from Hacker News will lead to an unsavory image. Just copy & paste it, instead.

https://www.jwz.org/blog/2018/11/weird-machines/#comment-192...

[js2]

Safe clickable link via deferrer:

http://www.dereferer.org/?https%3A%2F%2Fwww%2Ejwz%2Eorg%2Fbl...

[johnwyles]

DDoS of brogrammers and financially obsessed man-children. I think he nailed it. However the content in his pages is very lightweight and hosted in AWS it looks like so maybe that referrer logic pre-dates him hosting it and the DNA Lounge website there and... also because what he has to say is certifiably true. Good laugh.

[nikofeyn]

why does hacker news redirect the link like that? isn't this a major bug and security issue?

[msla]

Oh, joy. Now we have to have a disucussion about jwz' anti-autistic bullshit.

[ebcode]

I'm seeing some really interesting JavaScript techniques in the turtlevm.js[1] source.

This line in particular stands out: const code = String(work).trim().split("{").slice(1).join("{").slice(0, - 1).trim().replace("/0/", _turtlevmapi).replace("/1/", strCode);

It looks like the author is injecting the turtle code written by the user into a "work" function that removes dangerous objects (XMLHttpRequest, WebSocket, etc).

Can someone with experience writing a VM in JS point to a good reference on the topic?

[1]https://turtletoy.net/js/turtlevm.js?v=56

[whyonearth]

I certainly hope that isn't the intent, because there are other ways to generate network requests (new Image() and fetch(), for example). Sandboxing JS eval is a very hard problem and even Angular 1's "bulletproof" sandboxed template engine was repeatedly owned. I'd be wary of XSS on any site like this one.

[aarondf]

Go to this one [1], change the GEAR_NUM to like 30 and enjoy the rendering

1: https://turtletoy.net/turtle/9ddc6d4dc5

[azeirah]

Plotted!

http://imgur.com/gallery/CXLtbZA

[milancurcic]

Tweaking the value of PI2 is a lot of fun..

[azeirah]

Ahhh, love this site. I own an axidraw pen plotter, and because I'm feeling generous, I'll print every sketch made by people in this HN thread.

<3

[antoineMoPa]

I fear the method I used here will be really inefficient on a pen plotter though: https://turtletoy.net/turtle/63b170ed47

(Lots of useless moves happen while the pen is up)

[redbonsai]

How are you translating the sketches into files that work with Axidraw? I have one as well and would love to do the same!

[deyan]

Immediately took me back to Logo and 9 year old me trying to figure out how to move the turtle :) Great memories!

[guillaumec]

For anyone interested about this kind of things, I did something a bit similar for 3d voxel rendering: https://voxeltoy.com/, also inspired by shadertoy.

[antoineMoPa]

I have seen this site some days ago (reddit maybe?) and I really like the concept! The design is very clean!

One feature I'd like: A way to slow down the render so we can see the whole generation in slow-motion.

[gabriel34]

well, it is javascript, so you could implement something like https://stackoverflow.com/questions/951021/what-is-the-javas...

the async way doesn't seem to work inside the walk function, but the older (and uglier imo) way does

As an example here is the modified code for https://turtletoy.net/turtle/eed0f57234

  // You can find the Turtle API reference here: https://turtletoy.net/syntax
  Canvas.setpenopacity(1);
  
  // Global code will be evaluated once.
  const turtle = new Turtle();
  turtle.penup();
  turtle.goto(0,0);
  turtle.pendown();
  
  function sleep(ms) {
    return new Promise(resolve => setTimeout(resolve, ms));
  }
  function pausecomp(millis)
  {
      var date = new Date();
      var curDate = null;
      do { curDate = new Date(); }
      while(curDate-date < millis);
  }
  // The walk function will be called until it returns false.
  function walk(i) {
      turtle.forward(i);
      turtle.right(150);
      //await sleep(100); //await not valid inside the walk function
      pausecomp(50)
      return i < 200;
  }

edit: implemented: https://turtletoy.net/turtle/e99ca811ad

[keithxm23]

And once you can slow down the generation, it would also be lovely to highlight the line of code being executed as the picture was drawn!

[msurguy]

+1

[kayamon]

I am highly impressed that some of these actually implement wireframe hidden surface removal:

https://turtletoy.net/turtle/9ddc6d4dc5

[mrspeaker]

Not really in the true spirit of turtle (if it doesn't "go forward" I don't count it!), but I had to make this one based on the MAD computer program discussed here yesterday.

https://turtletoy.net/turtle/ba15abdde7

[drostie]

I saw yours and went for Buddhabrot: https://turtletoy.net/turtle/e196b49813

[DBYCZ]

This reminded me of a physics toy I saw ~10 years ago where you would draw simple two-dimensional robots with legs and muscles, optimize their gait, and race them.

If only I could remember the name of it...

[scrumbledober]

I am reminded of what i believe is the same thing constantly and can never find it. I always thought it was called something like Sodaracer but searches have been unsuccessful. I remember evolution algorithms to make the fastest amoeba wheels.

EDIT: soda constructor by sodaplay.

http://maciejmatyka.blogspot.com/2018/02/soda-constructor-re...

EDIT2: from that link, here is a playable open source recreation linked at the bottom

https://peterfidelman.github.io/constructor/

[_xgw]

Reminds me of https://dwitter.net: you get 140 characters to animate an HTML canvas.

[chime]

While TurtleToy is way more advanced, few years ago I built a small webapp that uses nested CSS to make recursive images: https://zetabee.com/weave/

Click [Help] button to get an idea of how it works. It was heavily inspired by Structure Synth but written from scratch to work with CSS3 in a modern browser.

[welly]

This takes me back. I remember learning Logo at school when I was 10 or 11 and had a project to do using Logo. For some reason I couldn't make it into school for a few weeks, I'm not sure if I was ill or something else but was going to miss the project hand in date, so I wrote the code on paper while I was at home as I didn't have a Logo compiler or interpreter for my ZX Spectrum. My teacher put my code into the interpreter and it ended up looking exactly as I had expected. I think it was a tank and used procedures/functions which was above and beyond what we'd been taught.

Of course Logo wasn't the most complex language ever but I remember being pretty pleased with myself having written a computer program on a bit of paper and it doing exactly what I'd visualised it to do.

[timbit42]

> Of course Logo wasn't the most complex language ever

Logo's turtle graphics aren't the most complex language ever, but underneath of it is a Lisp without the parentheses, which is quite powerful including list processing and recursion.

[ArtWomb]

I am so glad this exists. Turtle Graphics remains the best way to teach so many fundamental concepts. From recursion to path finding.

One feature that I wish existed was library import. Or community accepted set of extension modules. An easy way to call polar coordinates, Spirographs, matrix transforms, etc.

[viach]

Reminds me of Context Free Art https://www.contextfreeart.org/

They developed their own declarative language for generating art.

[agumonkey]

Some of them are super impressive. Well I mean full fledged 3d renderers

[ejo4041]

Is it possible to get vector files of some sort out of these? .SVG, .AI, .PDF, or something similar would be awesome.

Edit: I meant directly from the site. I could do it from my desktop using python.

PS, this is awesome!

[Jack5500]

Yes, there is a download button for each drawing

[nottwo]

These are great!

Also reminds me of the Forth Haiku Salon: https://forthsalon.appspot.com/

[etrautmann]

If you're into this, you might also be interested in robotic pen plotters. This article from last year kicked off a serious new hobby for me which combines code/art/robotics/etc and has been a ton of fun.

http://www.tobiastoft.com/posts/an-intro-to-pen-plotters