← Feed

Posts

• Post #2449923

  As promised, here's the Shadertoy page for a GPU shader that draws the hat tiling: https://www.shadertoy.com/view/s3lGD7. Hopefully the code makes sense (I've tried to organize it to be easy to work with), and people will find fun ways to play with it! :monotile:

• Post #2332239

  Recently, Sébastien Labbé and Peter Selinger posted a preprint (https://arxiv.org/pdf/2604.20964) that describes a sophisticated construction for the hat tiling, based on what's called a Markov partition (see the thread by @pieter at https://mathstodon.xyz/@pieter/116484517078239617 for more details). One nice side effect of their construction is that it provides a means of rendering the hat tiling on the GPU using a fragment shader. That's cool, because it requires a constant a...

• Post #1952676

  In the past few years, spicy topokki chips from Korea have become one of my favourite snack foods. They're the perfect blend of sweet, spice, salt, and crunchy. They're also very hard to get in my part of the world. Needless to say, that just makes them even more delicious.

• Post #1095979

  Yesterday, through a somewhat unlikely chain of events, I met a complete stranger who was wearing a t-shirt with a picture of me on it.

• Post #728691

  In my online undergraduate P5.js course, students are about to begin the module on motion and physics, including a bit of physics simulation using Matter.js. It suddenly occurred to me that I had never seen anybody put together this particular demo before, and I realized it had to be done. Messy source code at https://editor.p5js.org/isohedral/full/vJa5RiZWs.

• Post #670113

  Wow, I'm glad the internet enjoyed my silly demo so much. As I mentioned elsewhere, I tip my hat to the people who responded with their past implementations of the same idea. I wish the students in my undergraduate P5.js course were as enthusiastic about this material as all of you 🙃

• Post #565993

  There are a few different notations that are used to describe "regular" tilings (where we use "regular" in the informal sense of "simple arrangement of copies of a single shape"). The most important are probably Grünbaum and Shephard's incidence symbols for isohedral tilings, and Heesch and Kienzle's primitive tiling types. A system developed by Bigalke and Wippermann in the 1990s is intermediate between the other two. Talkin...

• Post #502466

  In my online undergraduate P5.js course, students are about to begin the module on motion and physics, including a bit of physics simulation using Matter.js. It suddenly occurred to me that I had never seen anybody put together this particular demo before, and I realized it had to be done. Messy source code at https://editor.p5js.org/isohedral/full/vJa5RiZWs.

• Post #302439

  January 31: GLSL day. Create an artwork using only shaders. I'm going to cheat a bit and share a work-in-progress image from a forthcoming paper by my PhD student Brian Do. This is a hyperbolic version of Kitaoka's Rotating Snakes illusion. The whole thing is rendered in real time in a browser-based app, using shaders. Pre-print and interactive tool coming soon. #genuary #genuary2026

• Post #302438

  The time has come. Me, Bill Murray, and a sweet vermouth on the rocks with a twist. Happy Groundhog Day.

• Post #302437

• Post #302436

  I'm not in the Epstein files, though someone else with my name is mentioned once or twice (as part of some US political campaign event). But I do know a few people who are mentioned. Interestingly, it appears that Epstein was subscribed to the Gathering 4 Gardner mailing list, and went so far as to make plans to attend G4G11 (2014). I was at that event. I don't remember one way or another whether he was there, but it's certainly possible.

• Post #302433

  My region, Kitchener-Waterloo, is often abbreviated KW. I just discovered that there's a perfect Unicode character for that: ㎾. https://unicodeplus.com/U+33BE