39 lines
685 B
TypeScript
39 lines
685 B
TypeScript
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// https://stackoverflow.com/a/6853926/232122
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export function distanceBetweenPointAndSegment(
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x: number,
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y: number,
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x1: number,
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y1: number,
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x2: number,
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y2: number
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) {
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const A = x - x1;
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const B = y - y1;
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const C = x2 - x1;
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const D = y2 - y1;
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const dot = A * C + B * D;
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const lenSquare = C * C + D * D;
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let param = -1;
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if (lenSquare !== 0) {
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// in case of 0 length line
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param = dot / lenSquare;
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}
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let xx, yy;
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if (param < 0) {
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xx = x1;
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yy = y1;
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} else if (param > 1) {
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xx = x2;
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yy = y2;
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} else {
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xx = x1 + param * C;
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yy = y1 + param * D;
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}
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const dx = x - xx;
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const dy = y - yy;
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return Math.hypot(dx, dy);
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}
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