1 # Code is Public Domain.
   2 
   3 import math # required because of 'sqrt' in 'distanceTo' function (and now rotation)
   4 
   5 def normalize(x1, y1, x2, y2):
   6     '''I am not sure what this is for, care to comment?'''
   7     return min(x1,x2), min(y1,y2), max(x1,x2), max(y1,y2)
   8 
   9 class Point:
  10     def __init__(self, x, y):
  11         self.x = x
  12         self.y = y
  13     def __add__(self, other):
  14         return Point(self.x+other.x, self.y+other.y)
  15     def __sub__(self, other):
  16         return Point(self.x-other.x, self.y-other.y)
  17     def __mul__( self, scalar ):
  18         return Point(self.x*scalar, self.y*scalar)
  19     def __div__(self, scalar):
  20         return Point(self.x/scalar, self.y/scalar)
  21     def __str__(self):
  22         return "(%s, %s)" % (self.x, self.y)
  23     def __repr__(self):
  24         return "%s(%r, %r)" % (self.__class__.__name__, self.x, self.y)
  25     def XY(self):
  26         '''Returns a tuple (x,y).'''
  27         return self.x,self.y
  28     def Clone(self):
  29         '''Returns a full copy of this point.''' 
  30         return Point(self.x, self.y)
  31     def Integerize(self):
  32         '''Rounds co-ordinate values to integers.'''
  33         self.x = int(self.x)
  34         self.y = int(self.y)
  35     def Floatize(self):
  36         '''Converts co-ordinate values to floating point (is this necessary?)'''
  37         self.x = float(self.x)
  38         self.y = float(self.y)
  39     def DistanceTo(self,pt):
  40         '''Distance between 2 points.'''
  41         dy = self.y - pt.y
  42         dx = self.x - pt.x
  43         return sqrt(dy*dy + dx*dx)
  44     def Move(newx,newy):
  45         '''Changes coordinates to those given.'''
  46         self.x = newx
  47         self.y = newy
  48     def MoveDelta(dx,dy):
  49         '''Move to new (x+dx,y+dy)'''
  50         self.x = self.x + dx
  51         self.y = self.y + dy
  52     def Rotate(self,theta):
  53         '''Clockwise rotation about origin, theta in Degrees.  Returns the new position as Point()'''
  54         # Err..this math is not exactly readable.  It is elementary though, involving only Pythogoras and basic trig.
  55           r2 = sqr(self.x)+sqr(self.y)
  56           tmp = math.tan(theta*math.pi/90 + math.atan(self.x/self.y))
  57           ret = Point()
  58           ret.x = math.sqrt(r2/(1+tmp*tmp))
  59           ret.y = ret.x * tmp
  60           return ret
  61     def RotateAbout(self,OtherPoint,theta):
  62         '''Clockwise rotation about another point.  Returns a Point() at new position'''
  63         tmpx = OtherPoint.x
  64         tmpy = OtherPoint.y
  65         self.MoveDelta(-tmpx,-tmpy)
  66         tmpPoint = self.Rotate(theta)
  67         tmpPoint.MoveDelta(tmpx,tmpy)
  68         return tmpPoint
  69 
  70 
  71 class Rect:
  72     def __init__(self, pt1, pt2):
  73         self.Set(pt1, pt2)
  74     def Contains(self, pt):
  75         x,y = pt.XY()
  76         return self.left <= x <= self.right and self.top <= y <= self.bottom
  77     def Set( self, pt1, pt2 ):
  78         extrema = normalize(pt1.x, pt1.y, pt2.x, pt2.y)
  79         self.left, self.top, self.right, self.bottom = extrema
  80     def Overlaps(self, other):
  81         return (self.right > other.left and self.left < other.right
  82                 and self.top < other.bottom and self.bottom > other.top)
  83     def GetTL(self):
  84         return Point(self.left, self.top)
  85     def GetBR(self):
  86         return Point(self.right, self.bottom)
  87     def ExpandedBy(self, n):
  88         p1 = Point(self.left-n, self.top+n)
  89         p2 = Point(self.right+n, self.bottom+n)
  90         return Rect(p1, p2)
  91     def TransformedByFunction(self, foo):
  92         p1 = Point(self.left,  self.top)
  93         p2 = Point(self.right, self.bottom)
  94         return Rect(foo(p1), foo(p2))
  95     def __str__( self ):
  96         return "<Rect (%s,%s)-(%s,%s)>" % (self.left,self.top,
  97                                            self.right,self.bottom)
  98     def __repr__(self):
  99         return "%s(%r, %r)" % (self.__class__.__name__,
 100                                Point(self.left, self.top),
 101                                Point(self.right, self.bottom))