Bounding Box Checking
=====================

See http://trac.gispython.org/projects/PCL/ticket/127.

Adding with bogus bounds
------------------------

  >>> import rtree
  >>> index = rtree.Rtree()
  >>> index.add(1, (0.0, 0.0, -1.0, 1.0))
  Traceback (most recent call last):
  ...
  ValueError: Bounding box is invalid: maxx < miny or maxy < miny

  >>> index.intersection((0.0, 0.0, -1.0, 1.0))
  Traceback (most recent call last):
  ...
  ValueError: Bounding box is invalid: maxx < miny or maxy < miny


