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export { intersectEllipse };
function intersectEllipse(node, rx, ry, point) {
// Formulae from: http://mathworld.wolfram.com/Ellipse-LineIntersection.html
var cx = node.x;
var cy = node.y;
var px = cx - point.x;
var py = cy - point.y;
var det = Math.sqrt(rx * rx * py * py + ry * ry * px * px);
var dx = Math.abs((rx * ry * px) / det);
if (point.x < cx) {
dx = -dx;
}
var dy = Math.abs((rx * ry * py) / det);
if (point.y < cy) {
dy = -dy;
}
return { x: cx + dx, y: cy + dy };
}