SVG arc to cubic bezier

A function that takes an SVG arc curve as input, and maps it to one or more cubic bezier curves.

I extracted the a2c function from SVG path, as I wanted to use it on its own.

All credit, thanks and respect goes to:

• Sergey Batishchev – @snb2013
• Vitaly Puzrin – @puzrin
• Alex Kocharin – @rlidwka

It blew my mind. Thank you!

Installation

npm install svg-arc-to-cubic-bezier

Usage

import arcToBezier from 'svg-arc-to-cubic-bezier';
 
const previousPoint = { x: 100, y: 100 }
 
const currentPoint = {
  x: 700,
  y: 100,
  curve: {
    type: 'arc',
    rx: 300,
    ry: 200,
    largeArcFlag: 30,
    sweepFlag: 0,
    xAxisRotation: 0,
  },
};
 
const curves = arcToBezier({
  px: previousPoint.x,
  py: previousPoint.y,
  cx: currentPoint.x,
  cy: currentPoint.y,
  rx: currentPoint.curve.rx,
  ry: currentPoint.curve.ry,
  xAxisRotation: currentPoint.curve.xAxisRotation,
  largeArcFlag: currentPoint.curve.largeArcFlag,
  sweepFlag: currentPoint.curve.sweepFlag,
});
 
curves.forEach( c => console.log( c ));
 
// [
//   {
//     x1: 159.7865795437111,
//     y1: 244.97474575043722,
//     x2: 342.5677510865157,
//     y2: 362.49999701503634,
//     x: 508.253174689854,
//     y: 362.4999967447917,
//   },
//   {
//     x1: 673.9385982931924,
//     y1: 362.49999647454695,
//     x2: 759.7865756485664,
//     y2: 244.97474477179443,
//     x: 699.9999995964145,
//     y: 99.99999902135724,
//   },
// ]