diff bGrease/geometry.py @ 41:ff3e395abf91

Renamed grease to bGrease (Basic Grease) to get rid of conflicts with an already installed grease.
author KarstenBock@gmx.net
date Mon, 05 Sep 2011 15:00:34 +0200
parents grease/geometry.py@bc88f7d5ca8b
children a6bbb732b27b
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/bGrease/geometry.py	Mon Sep 05 15:00:34 2011 +0200
@@ -0,0 +1,600 @@
+__version__ = "$Id$"
+__docformat__ = "reStructuredText"
+
+import operator
+import math
+import ctypes 
+
+class Vec2d(ctypes.Structure):
+    """2d vector class, supports vector and scalar operators,
+       and also provides a bunch of high level functions
+       """
+    __slots__ = ['x', 'y']
+    
+    @classmethod
+    def from_param(cls, arg):
+        return cls(arg)
+        
+    def __init__(self, x_or_pair, y = None):
+        
+        if y == None:
+            self.x = x_or_pair[0]
+            self.y = x_or_pair[1]
+        else:
+            self.x = x_or_pair
+            self.y = y
+ 
+    def __len__(self):
+        return 2
+ 
+    def __getitem__(self, key):
+        if key == 0:
+            return self.x
+        elif key == 1:
+            return self.y
+        else:
+            raise IndexError("Invalid subscript "+str(key)+" to Vec2d")
+ 
+    def __setitem__(self, key, value):
+        if key == 0:
+            self.x = value
+        elif key == 1:
+            self.y = value
+        else:
+            raise IndexError("Invalid subscript "+str(key)+" to Vec2d")
+ 
+    # String representaion (for debugging)
+    def __repr__(self):
+        return 'Vec2d(%s, %s)' % (self.x, self.y)
+    
+    # Comparison
+    def __eq__(self, other):
+        if hasattr(other, "__getitem__") and len(other) == 2:
+            return self.x == other[0] and self.y == other[1]
+        else:
+            return False
+    
+    def __ne__(self, other):
+        if hasattr(other, "__getitem__") and len(other) == 2:
+            return self.x != other[0] or self.y != other[1]
+        else:
+            return True
+ 
+    def __nonzero__(self):
+        return self.x or self.y
+ 
+    # Generic operator handlers
+    def _o2(self, other, f):
+        "Any two-operator operation where the left operand is a Vec2d"
+        if isinstance(other, Vec2d):
+            return Vec2d(f(self.x, other.x),
+                         f(self.y, other.y))
+        elif (hasattr(other, "__getitem__")):
+            return Vec2d(f(self.x, other[0]),
+                         f(self.y, other[1]))
+        else:
+            return Vec2d(f(self.x, other),
+                         f(self.y, other))
+ 
+    def _r_o2(self, other, f):
+        "Any two-operator operation where the right operand is a Vec2d"
+        if (hasattr(other, "__getitem__")):
+            return Vec2d(f(other[0], self.x),
+                         f(other[1], self.y))
+        else:
+            return Vec2d(f(other, self.x),
+                         f(other, self.y))
+ 
+    def _io(self, other, f):
+        "inplace operator"
+        if (hasattr(other, "__getitem__")):
+            self.x = f(self.x, other[0])
+            self.y = f(self.y, other[1])
+        else:
+            self.x = f(self.x, other)
+            self.y = f(self.y, other)
+        return self
+ 
+    # Addition
+    def __add__(self, other):
+        if isinstance(other, Vec2d):
+            return Vec2d(self.x + other.x, self.y + other.y)
+        elif hasattr(other, "__getitem__"):
+            return Vec2d(self.x + other[0], self.y + other[1])
+        else:
+            return Vec2d(self.x + other, self.y + other)
+    __radd__ = __add__
+    
+    def __iadd__(self, other):
+        if isinstance(other, Vec2d):
+            self.x += other.x
+            self.y += other.y
+        elif hasattr(other, "__getitem__"):
+            self.x += other[0]
+            self.y += other[1]
+        else:
+            self.x += other
+            self.y += other
+        return self
+ 
+    # Subtraction
+    def __sub__(self, other):
+        if isinstance(other, Vec2d):
+            return Vec2d(self.x - other.x, self.y - other.y)
+        elif (hasattr(other, "__getitem__")):
+            return Vec2d(self.x - other[0], self.y - other[1])
+        else:
+            return Vec2d(self.x - other, self.y - other)
+    def __rsub__(self, other):
+        if isinstance(other, Vec2d):
+            return Vec2d(other.x - self.x, other.y - self.y)
+        if (hasattr(other, "__getitem__")):
+            return Vec2d(other[0] - self.x, other[1] - self.y)
+        else:
+            return Vec2d(other - self.x, other - self.y)
+    def __isub__(self, other):
+        if isinstance(other, Vec2d):
+            self.x -= other.x
+            self.y -= other.y
+        elif (hasattr(other, "__getitem__")):
+            self.x -= other[0]
+            self.y -= other[1]
+        else:
+            self.x -= other
+            self.y -= other
+        return self
+ 
+    # Multiplication
+    def __mul__(self, other):
+        if isinstance(other, Vec2d):
+            return Vec2d(self.x*other.y, self.y*other.y)
+        if (hasattr(other, "__getitem__")):
+            return Vec2d(self.x*other[0], self.y*other[1])
+        else:
+            return Vec2d(self.x*other, self.y*other)
+    __rmul__ = __mul__
+    
+    def __imul__(self, other):
+        if isinstance(other, Vec2d):
+            self.x *= other.x
+            self.y *= other.y
+        elif (hasattr(other, "__getitem__")):
+            self.x *= other[0]
+            self.y *= other[1]
+        else:
+            self.x *= other
+            self.y *= other
+        return self
+ 
+    # Division
+    def __div__(self, other):
+        return self._o2(other, operator.div)
+    def __rdiv__(self, other):
+        return self._r_o2(other, operator.div)
+    def __idiv__(self, other):
+        return self._io(other, operator.div)
+ 
+    def __floordiv__(self, other):
+        return self._o2(other, operator.floordiv)
+    def __rfloordiv__(self, other):
+        return self._r_o2(other, operator.floordiv)
+    def __ifloordiv__(self, other):
+        return self._io(other, operator.floordiv)
+ 
+    def __truediv__(self, other):
+        return self._o2(other, operator.truediv)
+    def __rtruediv__(self, other):
+        return self._r_o2(other, operator.truediv)
+    def __itruediv__(self, other):
+        return self._io(other, operator.floordiv)
+ 
+    # Modulo
+    def __mod__(self, other):
+        return self._o2(other, operator.mod)
+    def __rmod__(self, other):
+        return self._r_o2(other, operator.mod)
+ 
+    def __divmod__(self, other):
+        return self._o2(other, divmod)
+    def __rdivmod__(self, other):
+        return self._r_o2(other, divmod)
+ 
+    # Exponentation
+    def __pow__(self, other):
+        return self._o2(other, operator.pow)
+    def __rpow__(self, other):
+        return self._r_o2(other, operator.pow)
+ 
+    # Bitwise operators
+    def __lshift__(self, other):
+        return self._o2(other, operator.lshift)
+    def __rlshift__(self, other):
+        return self._r_o2(other, operator.lshift)
+ 
+    def __rshift__(self, other):
+        return self._o2(other, operator.rshift)
+    def __rrshift__(self, other):
+        return self._r_o2(other, operator.rshift)
+ 
+    def __and__(self, other):
+        return self._o2(other, operator.and_)
+    __rand__ = __and__
+ 
+    def __or__(self, other):
+        return self._o2(other, operator.or_)
+    __ror__ = __or__
+ 
+    def __xor__(self, other):
+        return self._o2(other, operator.xor)
+    __rxor__ = __xor__
+ 
+    # Unary operations
+    def __neg__(self):
+        return Vec2d(operator.neg(self.x), operator.neg(self.y))
+ 
+    def __pos__(self):
+        return Vec2d(operator.pos(self.x), operator.pos(self.y))
+ 
+    def __abs__(self):
+        return Vec2d(abs(self.x), abs(self.y))
+ 
+    def __invert__(self):
+        return Vec2d(-self.x, -self.y)
+ 
+    # vectory functions
+    def get_length_sqrd(self): 
+        """Get the squared length of the vector.
+        It is more efficent to use this method instead of first call 
+        get_length() or access .length and then do a sqrt().
+        
+        :return: The squared length
+        """
+        return self.x**2 + self.y**2
+ 
+    def get_length(self):
+        """Get the length of the vector.
+        
+        :return: The length
+        """
+        return math.sqrt(self.x**2 + self.y**2)    
+    def __setlength(self, value):
+        length = self.get_length()
+        self.x *= value/length
+        self.y *= value/length
+    length = property(get_length, __setlength, doc = """Gets or sets the magnitude of the vector""")
+       
+    def rotate(self, angle_degrees):
+        """Rotate the vector by angle_degrees degrees clockwise."""
+        radians = -math.radians(angle_degrees)
+        cos = math.cos(radians)
+        sin = math.sin(radians)
+        x = self.x*cos - self.y*sin
+        y = self.x*sin + self.y*cos
+        self.x = x
+        self.y = y
+ 
+    def rotated(self, angle_degrees):
+        """Create and return a new vector by rotating this vector by 
+        angle_degrees degrees clockwise.
+        
+        :return: Rotated vector
+        """
+        radians = -math.radians(angle_degrees)
+        cos = math.cos(radians)
+        sin = math.sin(radians)
+        x = self.x*cos - self.y*sin
+        y = self.x*sin + self.y*cos
+        return Vec2d(x, y)
+    
+    def get_angle(self):
+        if (self.get_length_sqrd() == 0):
+            return 0
+        return math.degrees(math.atan2(self.y, self.x))
+    def __setangle(self, angle_degrees):
+        self.x = self.length
+        self.y = 0
+        self.rotate(angle_degrees)
+    angle = property(get_angle, __setangle, doc="""Gets or sets the angle of a vector""")
+ 
+    def get_angle_between(self, other):
+        """Get the angle between the vector and the other in degrees
+        
+        :return: The angle
+        """
+        cross = self.x*other[1] - self.y*other[0]
+        dot = self.x*other[0] + self.y*other[1]
+        return math.degrees(math.atan2(cross, dot))
+            
+    def normalized(self):
+        """Get a normalized copy of the vector
+        
+        :return: A normalized vector
+        """
+        length = self.length
+        if length != 0:
+            return self/length
+        return Vec2d(self)
+ 
+    def normalize_return_length(self):
+        """Normalize the vector and return its length before the normalization
+        
+        :return: The length before the normalization
+        """
+        length = self.length
+        if length != 0:
+            self.x /= length
+            self.y /= length
+        return length
+ 
+    def perpendicular(self):
+        return Vec2d(-self.y, self.x)
+    
+    def perpendicular_normal(self):
+        length = self.length
+        if length != 0:
+            return Vec2d(-self.y/length, self.x/length)
+        return Vec2d(self)
+        
+    def dot(self, other):
+        """The dot product between the vector and other vector
+            v1.dot(v2) -> v1.x*v2.x + v1.y*v2.y
+            
+        :return: The dot product
+        """
+        return float(self.x*other[0] + self.y*other[1])
+        
+    def get_distance(self, other):
+        """The distance between the vector and other vector
+        
+        :return: The distance
+        """
+        return math.sqrt((self.x - other[0])**2 + (self.y - other[1])**2)
+        
+    def get_dist_sqrd(self, other):
+        """The squared distance between the vector and other vector
+        It is more efficent to use this method than to call get_distance()
+        first and then do a sqrt() on the result.
+        
+        :return: The squared distance
+        """
+        return (self.x - other[0])**2 + (self.y - other[1])**2
+        
+    def projection(self, other):
+        other_length_sqrd = other[0]*other[0] + other[1]*other[1]
+        projected_length_times_other_length = self.dot(other)
+        return other*(projected_length_times_other_length/other_length_sqrd)
+    
+    def cross(self, other):
+        """The cross product between the vector and other vector
+            v1.cross(v2) -> v1.x*v2.y - v2.y-v1.x
+        
+        :return: The cross product
+        """
+        return self.x*other[1] - self.y*other[0]
+    
+    def interpolate_to(self, other, range):
+        return Vec2d(self.x + (other[0] - self.x)*range, self.y + (other[1] - self.y)*range)
+    
+    def convert_to_basis(self, x_vector, y_vector):
+        return Vec2d(self.dot(x_vector)/x_vector.get_length_sqrd(), self.dot(y_vector)/y_vector.get_length_sqrd())
+ 
+    # Extra functions, mainly for chipmunk
+    def cpvrotate(self, other):
+        return Vec2d(self.x*other.x - self.y*other.y, self.x*other.y + self.y*other.x)
+    def cpvunrotate(self, other):
+        return Vec2d(self.x*other.x + self.y*other.y, self.y*other.x - self.x*other.y)
+    
+    # Pickle, does not work atm.
+    def __getstate__(self):
+        return [self.x, self.y]
+        
+    def __setstate__(self, dict):
+        self.x, self.y = dict
+    def __newobj__(cls, *args):
+        return cls.__new__(cls, *args)    
+Vec2d._fields_ = [
+            ('x', ctypes.c_double),
+            ('y', ctypes.c_double),
+        ]
+
+
+class Vec2dArray(list):
+
+	def __init__(self, iterable=()):
+		list.__init__(self, (Vec2d(i) for i in iterable))
+
+	def __setitem__(self, index, value):
+		list.__setitem__(self, index, Vec2d(value))
+	
+	def append(self, value):
+		"""Append a vector to the array"""
+		list.append(self, Vec2d(value))
+	
+	def insert(self, index, value):
+		"""Insert a vector into the array"""
+		list.insert(self, index, Vec2d(value))
+	
+	def transform(self, offset=Vec2d(0,0), angle=0, scale=1.0):
+		"""Return a new transformed Vec2dArray"""
+		offset = Vec2d(offset)
+		angle = math.radians(-angle)
+		rot_vec = Vec2d(math.cos(angle), math.sin(angle))
+		xformed = Vec2dArray()
+		for vec in self:
+			xformed.append(vec.cpvrotate(rot_vec) * scale + offset)
+		return xformed
+	
+	def segments(self, closed=True):
+		"""Generate arrays of line segments connecting adjacent vetices
+		in this array, exploding the shape into it's constituent segments
+		"""
+		if len(self) >= 2:
+			last = self[0]
+			for vert in self[1:]:
+				yield Vec2dArray((last, vert))
+				last = vert
+			if closed:
+				yield Vec2dArray((last, self[0]))
+		elif self and closed:
+			yield Vec2dArray((self[0], self[0]))
+
+
+
+class Rect(ctypes.Structure):
+	"""Simple rectangle. Will gain more functionality as needed"""
+	_fields_ = [
+		('left', ctypes.c_double),
+		('top', ctypes.c_double),
+		('right', ctypes.c_double),
+		('bottom', ctypes.c_double),
+	]
+
+	def __init__(self, rect_or_left, bottom=None, right=None, top=None):
+		if bottom is not None:
+			assert right is not None and top is not None, "No enough arguments to Rect"
+			self.left = rect_or_left
+			self.bottom = bottom
+			self.right = right
+			self.top = top
+		else:
+			self.left = rect_or_left.left
+			self.bottom = rect_or_left.bottom
+			self.right = rect_or_left.right
+			self.top = rect_or_left.top
+
+	@property
+	def width(self):
+		"""Rectangle width"""
+		return self.right - self.left
+	
+	@property
+	def height(self):
+		"""Rectangle height"""
+		return self.top - self.bottom
+
+
+########################################################################
+## Unit Testing                                                       ##
+########################################################################
+if __name__ == "__main__":
+ 
+    import unittest
+    import pickle
+ 
+    ####################################################################
+    class UnitTestVec2d(unittest.TestCase):
+    
+        def setUp(self):
+            pass
+        
+        def testCreationAndAccess(self):
+            v = Vec2d(111, 222)
+            self.assert_(v.x == 111 and v.y == 222)
+            v.x = 333
+            v[1] = 444
+            self.assert_(v[0] == 333 and v[1] == 444)
+ 
+        def testMath(self):
+            v = Vec2d(111,222)
+            self.assertEqual(v + 1, Vec2d(112, 223))
+            self.assert_(v - 2 == [109, 220])
+            self.assert_(v * 3 == (333, 666))
+            self.assert_(v / 2.0 == Vec2d(55.5, 111))
+            #self.assert_(v / 2 == (55, 111)) # Not supported since this is a c_float structure in the bottom
+            self.assert_(v ** Vec2d(2, 3) == [12321, 10941048])
+            self.assert_(v + [-11, 78] == Vec2d(100, 300))
+            #self.assert_(v / [11,2] == [10,111]) # Not supported since this is a c_float structure in the bottom
+ 
+        def testReverseMath(self):
+            v = Vec2d(111, 222)
+            self.assert_(1 + v == Vec2d(112, 223))
+            self.assert_(2 - v == [-109, -220])
+            self.assert_(3 * v == (333, 666))
+            #self.assert_([222,999] / v == [2,4]) # Not supported since this is a c_float structure in the bottom
+            self.assert_([111, 222] ** Vec2d(2, 3) == [12321, 10941048])
+            self.assert_([-11, 78] + v == Vec2d(100, 300))
+ 
+        def testUnary(self):
+            v = Vec2d(111, 222)
+            v = -v
+            self.assert_(v == [-111, -222])
+            v = abs(v)
+            self.assert_(v == [111, 222])
+ 
+        def testLength(self):
+            v = Vec2d(3,4)
+            self.assert_(v.length == 5)
+            self.assert_(v.get_length_sqrd() == 25)
+            self.assert_(v.normalize_return_length() == 5)
+            self.assertAlmostEquals(v.length, 1)
+            v.length = 5
+            self.assert_(v == Vec2d(3, 4))
+            v2 = Vec2d(10, -2)
+            self.assert_(v.get_distance(v2) == (v - v2).get_length())
+            
+        def testAngles(self):            
+            v = Vec2d(0, 3)
+            self.assertEquals(v.angle, 90)
+            v2 = Vec2d(v)
+            v.rotate(-90)
+            self.assertEqual(v.get_angle_between(v2), 90)
+            v2.angle -= 90
+            self.assertEqual(v.length, v2.length)
+            self.assertEquals(v2.angle, 0)
+            self.assertEqual(v2, [3, 0])
+            self.assert_((v - v2).length < .00001)
+            self.assertEqual(v.length, v2.length)
+            v2.rotate(300)
+            self.assertAlmostEquals(v.get_angle_between(v2), -60, 5) # Allow a little more error than usual (floats..)
+            v2.rotate(v2.get_angle_between(v))
+            angle = v.get_angle_between(v2)
+            self.assertAlmostEquals(v.get_angle_between(v2), 0)  
+ 
+        def testHighLevel(self):
+            basis0 = Vec2d(5.0, 0)
+            basis1 = Vec2d(0, .5)
+            v = Vec2d(10, 1)
+            self.assert_(v.convert_to_basis(basis0, basis1) == [2, 2])
+            self.assert_(v.projection(basis0) == (10, 0))
+            self.assert_(basis0.dot(basis1) == 0)
+            
+        def testCross(self):
+            lhs = Vec2d(1, .5)
+            rhs = Vec2d(4, 6)
+            self.assert_(lhs.cross(rhs) == 4)
+            
+        def testComparison(self):
+            int_vec = Vec2d(3, -2)
+            flt_vec = Vec2d(3.0, -2.0)
+            zero_vec = Vec2d(0, 0)
+            self.assert_(int_vec == flt_vec)
+            self.assert_(int_vec != zero_vec)
+            self.assert_((flt_vec == zero_vec) == False)
+            self.assert_((flt_vec != int_vec) == False)
+            self.assert_(int_vec == (3, -2))
+            self.assert_(int_vec != [0, 0])
+            self.assert_(int_vec != 5)
+            self.assert_(int_vec != [3, -2, -5])
+        
+        def testInplace(self):
+            inplace_vec = Vec2d(5, 13)
+            inplace_ref = inplace_vec
+            inplace_src = Vec2d(inplace_vec)    
+            inplace_vec *= .5
+            inplace_vec += .5
+            inplace_vec /= (3, 6)
+            inplace_vec += Vec2d(-1, -1)
+            alternate = (inplace_src*.5 + .5)/Vec2d(3, 6) + [-1, -1]
+            self.assertEquals(inplace_vec, inplace_ref)
+            self.assertEquals(inplace_vec, alternate)
+        
+        def testPickle(self):
+            return # pickling does not work atm
+            testvec = Vec2d(5, .3)
+            testvec_str = pickle.dumps(testvec)
+            loaded_vec = pickle.loads(testvec_str)
+            self.assertEquals(testvec, loaded_vec)
+    
+    ####################################################################
+    unittest.main()
+