Check if BoundingBox a intersects with BoundingBox b.

def do_bb_intersect(a, b):
    """Check if BoundingBox a intersects with BoundingBox b."""
    return a.p1.x <= b.p2.x \
        and a.p2.x >= b.p1.x \
        and a.p1.y <= b.p2.y \
        and a.p2.y >= b.p1.y