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function getBounds(curve) {
    var px;
    var py;
    var qx;
    var qy;
    var rx;
    var ry;
    var sx;
    var sy;
    var tx;
    var ty;
    var tobx;
    var toby;
    var tocx;
    var tocy;
    var todx;
    var tody;
    var toqx;
    var toqy;
    var torx;
    var tory;
    var totx;
    var toty;
    var step;
    var x;
    var y;
    var minX;
    var minY;
    var maxX;
    var maxY;
    var ax = curve[0].x;
    var ay = curve[0].y;
    var bx = curve[1].x;
    var by = curve[1].y;
    var cx = curve[2].x;
    var cy = curve[2].y;
    var dx = curve[3].x;
    var dy = curve[3].y;
    var ITERATIONS_COUNT = 250;

    minX = minY = Number.POSITIVE_INFINITY;
    maxX = maxY = Number.NEGATIVE_INFINITY;

    tobx = bx - ax;
    toby = by - ay;
    tocx = cx - bx;
    tocy = cy - by;
    todx = dx - cx;
    tody = dy - cy;
    step = 1 / ITERATIONS_COUNT;

    for (var i = 0; i < ITERATIONS_COUNT; i++) {
        var d = i * step;
        px = ax + d * tobx;
        py = ay + d * toby;
        qx = bx + d * tocx;
        qy = by + d * tocy;
        rx = cx + d * todx;
        ry = cy + d * tody;
        toqx = qx - px;
        toqy = qy - py;
        torx = rx - qx;
        tory = ry - qy;

        sx = px + d * toqx;
        sy = py + d * toqy;
        tx = qx + d * torx;
        ty = qy + d * tory;
        totx = tx - sx;
        toty = ty - sy;

        x = sx + d * totx;
        y = sy + d * toty;

        minX = Math.min(minX, x);
        minY = Math.min(minY, y);
        maxX = Math.max(maxX, x);
        maxY = Math.max(maxY, y);
    }

    return {
        x: minX,
        y: minY,
        width: maxX - minX,
        height: maxY - minY
    };
}