30 lines
752 B
JavaScript
30 lines
752 B
JavaScript
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define(function () {
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return {
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distance: function distance(a, b) {
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return Math.pow(a.x - b.x, 2) + Math.pow(a.y - b.y, 2);
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},
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distancePoint: function distancePoint(a, b) {
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return Math.sqrt(distance(a, b));
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},
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distanceLink: function distanceLink(p, a, b) {
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/* http://stackoverflow.com/questions/849211 */
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var l2 = distance(a, b);
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if (l2 === 0) {
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return distance(p, a);
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}
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var t = ((p.x - a.x) * (b.x - a.x) + (p.y - a.y) * (b.y - a.y)) / l2;
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if (t < 0) {
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return distance(p, a);
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} else if (t > 1) {
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return distance(p, b);
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}
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return distancePoint(p, {
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x: a.x + t * (b.x - a.x),
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y: a.y + t * (b.y - a.y)
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});
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}
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};
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});
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