Find the intersection points of two circles

intersection.js

d = hypot(B.x - A.x, B.y - A.y)

if (d <= A.r + B.r && d >= abs(B.r - A.r)) {

  ex = (B.x - A.x) / d
  ey = (B.y - A.y) / d

  x = (A.r * A.r - B.r * B.r + d * d) / (2 * d)
  y = sqrt(A.r * A.r - x * x)

  P1 = {
    x: A.x + x * ex - y * ey,
    y: A.y + x * ey + y * ex
  }

  P2 = {
    x: A.x + x * ex + y * ey,
    y: A.y + x * ey - y * ex
  }

} else {
    // No Intersection, far outside or one circle within the other
    P1 = P2 = null
}