point-in-svg-polygon
v1.0.25
Published
Determine if a point is inside an SVG polygon.
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point-in-svg-polygon
Determine if an point is inside a polygon
Works with arbitrary polygons (as in: curves!) and is usable in Node.JS as well as in your browser (through Browserify).
What it does
Given an SVG path and a point, it'll tell you whether the point lies within the SVG path.
For instance:
Color | Inside red shape (convex)? | Inside blue shape (concave)? ------ | -------------------------- | ---------------------------- Red | No | No Green | Yes | Yes Blue | Yes | No Orange | No | Yes
Usage
Give it a point and a path string:
var pointInSvgPolygon = require("point-in-svg-polygon");
// See the path specification for the correct format
// https://developer.mozilla.org/en/docs/Web/SVG/Tutorial/Paths
var pathString = "M1,1 C1,1 501,1 501,501 C501,1001 1,1001 1,1001 L1,1 Z";
var result = pointInSvgPolygon.isInside([x, y], pathString);
You can amortize the path splitting by performing it once:
var pointInSvgPolygon = require("point-in-svg-polygon");
// See the path specification for the correct format
// https://developer.mozilla.org/en/docs/Web/SVG/Tutorial/Paths
var pathString = "M1,1 C1,1 501,1 501,501 C501,1001 1,1001 1,1001 L1,1 Z";
var segments = pointInSvgPolygon.segments(pathString);
// Use it multiple times:
var result = pointInSvgPolygon.isInside([x, y], segments);
This is useful if you have to test a lot of points.
Credits
Originally based on the work by Kevin Lindsey. Severly trimmed down: 6.3Kb footprint when minified, drops down to 2.9Kb when gzipped.
License
Copyright (c) 2016, Ruben Vermeersch
Copyright (c) 2013, Kevin Lindsey
All rights reserved.
Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:
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contributors may be used to endorse or promote products derived from
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