//
// function to compute bounding box of two rectangles
//
// input, output tuples are of the form (x, y, width, height)
// where x, y are coordinates of top left corner in coordinate system
// with (0,0) as its top left corner
//

// (these functions are not needed since Scala has min and max operators,
// but we wrote them in class so keep them)
def min(i1 : Int, i2 : Int) : Int = if (i1 < i2) i1 else i2
def max(i1 : Int, i2 : Int) : Int = if (i1 > i2) i1 else i2

def bbox(r1 : (Int,Int,Int,Int),  r2 : (Int,Int,Int,Int)) : (Int,Int,Int,Int) = {
  val (x1, y1, w1, h1) = r1
  val (x2, y2, w2, h2) = r2
  val x = min(x1, x2)
  val y = min(y1, y2)
  val right1 = x1 + w1
  val right2 = x2 + w2
  val w = max(right1, right2) - x
  val bottom1 = y1 + h1
  val bottom2 = y2 + h2
  val h = max(bottom1, bottom2) - y
  (x, y, w, h)
}