nowfound

Life & fun · June 20, 2024

IM

I made a puzzle game that gently introduces my favorite math mysteries

This is the first iteration of a short game I’m making that tries to interactively explain some of my favorite math questions / ideas. My goal is mostly to get the player curious and not necessarily to explain absolutely everything. There were a lot of fun technical parts to building this: - For implementation reasons, it’s much easier if the lines all have integer intersection points with each other. To do this, when a new line is added I “cheat” by rounding intersections to integers and then splitting the old lines at the intersection into new linds (with potentially different slopes)…

In plain words

This puzzle game introduces mathematical concepts through interactive gameplay, designed to spark curiosity rather than provide complete explanations. Created by Rahul Ilango, it features puzzles involving lines and geometric intersections across real-world maps including the UK, South America, and the US West Coast. The game uses canvas-based rendering and topojson to accurately represent geographic features while maintaining integer intersection points for technical efficiency. It's aimed at players interested in exploring mathematical ideas through hands-on puzzle solving.

written from the facts on this page · September 2026

From the sources

In the maker’s words, at launch

This is the first iteration of a short game I’m making that tries to interactively explain some of my favorite math questions / ideas. My goal is mostly to get the player curious and not necessarily to explain absolutely everything. There were a lot of fun technical parts to building this: - For implementation reasons, it’s much easier if the lines all have integer intersection points with each other. To do this, when a new line is added I “cheat” by rounding intersections to integers and then splitting the old lines at the intersection into new linds (with potentially different slopes) going through the rounded point - I had to draw semi accurate maps of actual places (UK, South America, US west coast) in the HTML canvas using just line segments. I tried a few different solutions, including using SVG data. I ended up using the topojson library to give nice line approximations to GeoJSON maps - I use a simple backtracking algorithm to handle the live coloring of graphs - I use turf.js’s polygonize function to handle finding polygons from line segments (very happy I didn’t have to implement this myself!) - I wanted to make the game as mobile friendly as possible (don’t think I’ve nailed this quite yet) There were also a few tradeoffs I made: - I wanted give links earlier in the game for players to learn more, but I decided to wait until the end to maintain the flow of the game - In order to make the game more mobile-friendly, I generally stuck to maps with a small number of regions (at least for maps people have to interact with them). So for the most part all of the instances in the game are “easy”

Does the same job

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  • IM
    I made a math puzzle game. Hope you like it2025 · madmonk13.github.io · ▲35

    I've been playing with this for quite some time and I think it's finally ready for public consumption. All feedback welcome.

  • Mr Math2015 · ▲102

    Math game. Looks easy. Is hard.

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    Slices – puzzle game2020 · slices.ovh · ▲219
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    Dozenal – A Game of Spatial ArithmeticJul 2026 · dozenal.game · ▲16

    Hello HN! We're Rory and Chris, and we've made a game called Dozenal[0], a grid-based number puzzle game where the objective is to use all the tiles on the board to create totals of 12 (hence the name). We think the mechanic is quite unique, although keen to hear if people know of similar games! You essentially drag tiles across the board, and the distance between two numbers decides the arithmetic operation when they connect to each other: zero spaces is addition, one space is subtraction, two spaces is multiplication: e.g. 5 → 4 = 9 5 → _ → 4 = 1 5 → _ → _ → 4 = 20 We've spent the past…

  • MN
    My New Puzzle Game2024 · shovemedia.com · ▲9

    This is an idea I’ve been kicking around for a long time, and I decided to finally code it up. In the same way that Scrabble decomposes words into letters, what if there was a game that decomposed letters into sub-shapes? There’s a lot of directions this could go, and I’m still exploring the possibility space. Enjoy. Suggestions welcome. It doesn’t have a real name yet.

  • PG
    Perfect Grid – my first iOS numbers puzzle game2014 · itunes.apple.com · ▲20

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