svg-path-to-polygons

Node package that converts path commands for an SVG path to polygonal points.

Features

• Sparsely represents linear portions of the path by the minimal number of points.
• Does not skip any imporant features.
• Uses adaptive subsampling for curves to represent them exactly in the fewest number of points, with an arbitrary tolerance.

Installation

npm install svg-path-to-polygons

Usage

const { pathDataToPolys } = require('../svg-path-to-polygons.js');
let pathData = 'M5,15 c5.5,0 10-4.5 10,-10 h10';
let points = pathDataToPolys(pathData, {tolerance:1, decimals:1});
console.log(points);
/*******************************************************************
[
  [ [5,15],[7,14.8],[10.6,13.3],[13.3,10.6],[14.8,7],[15,5],[25,5] ]
]
********************************************************************/

Note that the output for every path is an array of polygons/polylines (even if there is only one), where each polygon/polyline is an array of points, and where each point is an array of two numbers.

Each polygon/polyline also includes a custom closed property that defines whether the SVG subpath was closed (i.e. ended with a z or Z command).

The optional tolerance option specifies how far (in SVG coordinates) the polygon path may deviate from ideal curves. If not supplied, it defaults to 1.

The optional decimals option controls the precision of values produces for each point. Only non-negative values are currently supported. If unspecified, full precision is used for each number.

TODO (aka Known Limitations)

• Need to support quadratic Bézier commands.
• Need to support arc commands.
• Subsample linear sections if they are within the tolerance.
• Support negative values for decimals.

License, Contact, and Support

Copyright 2017 Gavin Kistner (!@phrogz.net) MIT License. See LICENSE file for details.

Please file bugs and feature requests on the GitHub page.