Function segmentContains

docs/app/js/sanddance-app.js:130624–130627

(a, b, c)

    return contains1;
}
function segmentContains(a, b, c) {
    var i;
    return collinear(a, b, c) && within(a[i = +(a[0] === b[0])], c[i], b[i]);
}
function collinear(a, b, c) {
    return (b[0] - a[0]) * (c[1] - a[1]) === (c[0] - a[0]) * (b[1] - a[1]);
}