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???????????? $(x_1, y_1)$ ? $(x_2, y_2)$???????????????????????

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function getDistanceP2L(point, line) {
    const x1 = line.startPoint.x;
    const y1 = line.startPoint.y;
    const x2 = line.endPoint.x;
    const y2 = line.endPoint.y;
    const x0 = point.x;
    const y0 = point.y;
    // ???????????
    const k = x1 === x2 ? 10000 : (y2 - y1) / (x2 - x1);
    const a = k;
    const b = -1;
    const c = y1 - k * x1;
    // ????
    const d = Math.abs(a * x0 + b * y0 + c) / Math.sqrt(a * a + b * b);
    // ??????
    const px = (b * b * x0 - a * b * y0 - a * c) / (a * a + b * b);
    const py = (a * a * y0 - a * b * x0 - b * c) / (a * a + b * b);
    return [d, new Point(px, py)];
}

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