poly-overlap

Geometry utiltiy for node.js and web.

Check if

• polygons overlap
• point inside polygon
• lines intersect
• polygon boundaries

Install

npm install poly-overlap

Usage

Polygons overlap

const p0 = [[0,0], [1,0], [1,1]];
const p1 = [[0.5,0.5], [1.5,0.5], [1.5,1.5]];
assert(pu.overlap(p0, p1)===true);

Line segments intersect

assert(pu.intersect(0,0, 1,1, 0,1, 1,0)===true);

Point inside polygon

const point = [1,1];
const poly = [[0,0], [2,0], [2,2], [0,2], [0,0]];
assert(pu.inside(point, poly)===true);

Tests

mocha

Sources

• http://math.stackexchange.com/questions/254569/concave-polygons-overlapping-test
• http://ptspts.blogspot.no/2010/06/how-to-determine-if-two-line-segments.html
• http://www.ecse.rpi.edu/Homepages/wrf/Research/Short_Notes/pnpoly.html