Turtle graphics is a popular way for introducing programming to non-programmers.
This is a simple turtle graphics implementation in JavaScript that works in browser.
Imagine a robotic turtle starting at (0, 0) in the x-y plane.
Give it the command D(50), and it moves (on-screen) 50 pixels in the direction it is facing, drawing a line as it moves.
Give it the command +(45), and it rotates in-place 45 degrees counter-clockwise.
There are many other commands as well as variables, conditions, loops and procedures.
Online: https://harag.cz/app/turtle
- 2021-03-02: The first commit
- 2021-04-07: Turtle language finalized (hasn't been touched since)
- 2022-10-12: Examples – from simple to advanced, right next to the editor
- 2022-10-17: Publishing
- 2023-04-08: The codebase moved into this separate Git repository and migrated to Rollup.js
- 2023-04-10: PNG export introduced
- 2023-10-30: Migration to Bootstrap 5
npm install to install dependencies.
npm run build builds the library to dist.
npm run dev builds the library, then keeps rebuilding it whenever the source files change using rollup-watch.
npm test builds the library, then tests it.
- TODO: on exception - ability to determine position in source
Turtle language ideas:
- TODO: (?) allow argument list without parenthesis
- TODO: text - T("hello")
- TODO: stroke pattern - P("dotted"), P("dashed"), P(10, 5)...
- TODO: colors using string - B("red")...
- TODO: bezier curve (B)
- TODO: introduce optimizing painter - merge sequences like DDD, M(10)M(50, 20)...