3D Vector utility class

Vec3D.py

########################################################################
import operator
import math
 
class Vec3d(object):
	"""3d vector class, supports vector and scalar operators,
		and also provides a bunch of high level functions.
		reproduced from the vec2d class on the pygame wiki site.
		"""
	__slots__ = ['x', 'y', 'z']
 
	def __init__(self, x_or_triple, y = None, z = None):
		if y == None:
			self.x = x_or_triple[0]
			self.y = x_or_triple[1]
			self.z = x_or_triple[2]
		else:
			self.x = x_or_triple
			self.y = y
			self.z = z
 
	def __len__(self):
		return 3
 
	def __getitem__(self, key):
		if key == 0:
			return self.x
		elif key == 1:
			return self.y
		elif key == 2:
			return self.z
		else:
			raise IndexError("Invalid subscript "+str(key)+" to Vec3d")
 
	def __setitem__(self, key, value):
		if key == 0:
			self.x = value
		elif key == 1:
			self.y = value
		elif key == 2:
			self.z = value
		else:
			raise IndexError("Invalid subscript "+str(key)+" to Vec3d")
 
	# String representaion (for debugging)
	def __repr__(self):
		return 'Vec3d(%s, %s, %s)' % (self.x, self.y, self.z)
	
	# Comparison
	def __eq__(self, other):
		if hasattr(other, "__getitem__") and len(other) == 3:
			return self.x == other[0] and self.y == other[1] and self.z == other[2]
		else:
			return False
	
	def __ne__(self, other):
		if hasattr(other, "__getitem__") and len(other) == 3:
			return self.x != other[0] or self.y != other[1] or self.z != other[2]
		else:
			return True
 
	def __nonzero__(self):
		return self.x or self.y or self.z
 
	# Generic operator handlers
	def _o2(self, other, f):
		"Any two-operator operation where the left operand is a Vec3d"
		if isinstance(other, Vec3d):
			return Vec3d(f(self.x, other.x),
						 f(self.y, other.y),
						 f(self.z, other.z))
		elif (hasattr(other, "__getitem__")):
			return Vec3d(f(self.x, other[0]),
						 f(self.y, other[1]),
						 f(self.z, other[2]))
		else:
			return Vec3d(f(self.x, other),
						 f(self.y, other),
						 f(self.z, other))
 
	def _r_o2(self, other, f):
		"Any two-operator operation where the right operand is a Vec3d"
		if (hasattr(other, "__getitem__")):
			return Vec3d(f(other[0], self.x),
						 f(other[1], self.y),
						 f(other[2], self.z))
		else:
			return Vec3d(f(other, self.x),
						 f(other, self.y),
						 f(other, self.z))
 
	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])
			self.z = f(self.z, other[2])
		else:
			self.x = f(self.x, other)
			self.y = f(self.y, other)
			self.z = f(self.z, other)
		return self
 
	# Addition
	def __add__(self, other):
		if isinstance(other, Vec3d):
			return Vec3d(self.x + other.x, self.y + other.y, self.z + other.z)
		elif hasattr(other, "__getitem__"):
			return Vec3d(self.x + other[0], self.y + other[1], self.z + other[2])
		else:
			return Vec3d(self.x + other, self.y + other, self.z + other)
	__radd__ = __add__
	
	def __iadd__(self, other):
		if isinstance(other, Vec3d):
			self.x += other.x
			self.y += other.y
			self.z += other.z
		elif hasattr(other, "__getitem__"):
			self.x += other[0]
			self.y += other[1]
			self.z += other[2]
		else:
			self.x += other
			self.y += other
			self.z += other
		return self
 
	# Subtraction
	def __sub__(self, other):
		if isinstance(other, Vec3d):
			return Vec3d(self.x - other.x, self.y - other.y, self.z - other.z)
		elif (hasattr(other, "__getitem__")):
			return Vec3d(self.x - other[0], self.y - other[1], self.z - other[2])
		else:
			return Vec3d(self.x - other, self.y - other, self.z - other)
	def __rsub__(self, other):
		if isinstance(other, Vec3d):
			return Vec3d(other.x - self.x, other.y - self.y, other.z - self.z)
		if (hasattr(other, "__getitem__")):
			return Vec3d(other[0] - self.x, other[1] - self.y, other[2] - self.z)
		else:
			return Vec3d(other - self.x, other - self.y, other - self.z)
	def __isub__(self, other):
		if isinstance(other, Vec3d):
			self.x -= other.x
			self.y -= other.y
			self.z -= other.z
		elif (hasattr(other, "__getitem__")):
			self.x -= other[0]
			self.y -= other[1]
			self.z -= other[2]
		else:
			self.x -= other
			self.y -= other
			self.z -= other
		return self
 
	# Multiplication
	def __mul__(self, other):
		if isinstance(other, Vec3d):
			return Vec3d(self.x*other.x, self.y*other.y, self.z*other.z)
		if (hasattr(other, "__getitem__")):
			return Vec3d(self.x*other[0], self.y*other[1], self.z*other[2])
		else:
			return Vec3d(self.x*other, self.y*other, self.z*other)
	__rmul__ = __mul__
	
	def __imul__(self, other):
		if isinstance(other, Vec3d):
			self.x *= other.x
			self.y *= other.y
			self.z *= other.z
		elif (hasattr(other, "__getitem__")):
			self.x *= other[0]
			self.y *= other[1]
			self.z *= other[2]
		else:
			self.x *= other
			self.y *= other
			self.z *= 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, operator.divmod)
	def __rdivmod__(self, other):
		return self._r_o2(other, operator.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 Vec3d(operator.neg(self.x), operator.neg(self.y), operator.neg(self.z))
 
	def __pos__(self):
		return Vec3d(operator.pos(self.x), operator.pos(self.y), operator.pos(self.z))
 
	def __abs__(self):
		return Vec3d(abs(self.x), abs(self.y), abs(self.z))
 
	def __invert__(self):
		return Vec3d(-self.x, -self.y, -self.z)
 
	# vectory functions
	def get_length_sqrd(self): 
		return self.x**2 + self.y**2 + self.z**2
 
	def get_length(self):
		return math.sqrt(self.x**2 + self.y**2 + self.z**2)		 
	def __setlength(self, value):
		length = self.get_length()
		self.x *= value/length
		self.y *= value/length
		self.z *= value/length
	length = property(get_length, __setlength, None, "gets or sets the magnitude of the vector")
		
	def rotate_around_z(self, angle_degrees):
		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 rotate_around_x(self, angle_degrees):
		radians = math.radians(angle_degrees)
		cos = math.cos(radians)
		sin = math.sin(radians)
		y = self.y*cos - self.z*sin
		z = self.y*sin + self.z*cos
		self.y = y
		self.z = z
 
	def rotate_around_y(self, angle_degrees):
		radians = math.radians(angle_degrees)
		cos = math.cos(radians)
		sin = math.sin(radians)
		z = self.z*cos - self.x*sin
		x = self.z*sin + self.x*cos
		self.z = z
		self.x = x
 
	def rotated_around_z(self, angle_degrees):
		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 Vec3d(x, y, self.z)
	
	def rotated_around_x(self, angle_degrees):
		radians = math.radians(angle_degrees)
		cos = math.cos(radians)
		sin = math.sin(radians)
		y = self.y*cos - self.z*sin
		z = self.y*sin + self.z*cos
		return Vec3d(self.x, y, z)
	
	def rotated_around_y(self, angle_degrees):
		radians = math.radians(angle_degrees)
		cos = math.cos(radians)
		sin = math.sin(radians)
		z = self.z*cos - self.x*sin
		x = self.z*sin + self.x*cos
		return Vec3d(x, self.y, z)
	
	def get_angle_around_z(self):
		if (self.get_length_sqrd() == 0):
			return 0
		return math.degrees(math.atan2(self.y, self.x))
	def __setangle_around_z(self, angle_degrees):
		self.x = math.sqrt(self.x**2 + self.y**2)
		self.y = 0
		self.rotate_around_z(angle_degrees)
	angle_around_z = property(get_angle_around_z, __setangle_around_z, None, "gets or sets the angle of a vector in the XY plane")
 
	def get_angle_around_x(self):
		if (self.get_length_sqrd() == 0):
			return 0
		return math.degrees(math.atan2(self.z, self.y))
	def __setangle_around_x(self, angle_degrees):
		self.y = math.sqrt(self.y**2 + self.z**2)
		self.z = 0
		self.rotate_around_x(angle_degrees)
	angle_around_x = property(get_angle_around_x, __setangle_around_x, None, "gets or sets the angle of a vector in the YZ plane")
 
	def get_angle_around_y(self):
		if (self.get_length_sqrd() == 0):
			return 0
		return math.degrees(math.atan2(self.x, self.z))
	def __setangle_around_y(self, angle_degrees):
		self.z = math.sqrt(self.z**2 + self.x**2)
		self.x = 0
		self.rotate_around_y(angle_degrees)
	angle_around_y = property(get_angle_around_y, __setangle_around_y, None, "gets or sets the angle of a vector in the ZX plane")
 
	def get_angle_between(self, other):
		v1 = self.normalized()
		v2 = Vec3d(other)
		v2.normalize_return_length()
		return math.degrees(math.acos(v1.dot(v2)))
			
	def normalized(self):
		length = self.length
		if length != 0:
			return self/length
		return Vec3d(self)
 
	def normalize_return_length(self):
		length = self.length
		if length != 0:
			self.x /= length
			self.y /= length
			self.z /= length
		return length
 
	def dot(self, other):
		return float(self.x*other[0] + self.y*other[1] + self.z*other[2])
		
	def get_distance(self, other):
		return math.sqrt((self.x - other[0])**2 + (self.y - other[1])**2 + (self.z - other[2])**2)
		
	def get_dist_sqrd(self, other):
		return (self.x - other[0])**2 + (self.y - other[1])**2 + (self.z - other[2])**2
		
	def projection(self, other):
		other_length_sqrd = other[0]*other[0] + other[1]*other[1] + other[2]*other[2]
		projected_length_times_other_length = self.dot(other)
		return other*(projected_length_times_other_length/other_length_sqrd)
	
	def cross(self, other):
		return Vec3d(self.y*other[2] - self.z*other[1], self.z*other[0] - self.x*other[2], self.x*other[1] - self.y*other[0])
	
	def interpolate_to(self, other, range):
		return Vec3d(self.x + (other[0] - self.x)*range, self.y + (other[1] - self.y)*range, self.z + (other[2] - self.z)*range)
	
	def convert_to_basis(self, x_vector, y_vector, z_vector):
		return Vec3d(self.dot(x_vector)/x_vector.get_length_sqrd(),
			self.dot(y_vector)/y_vector.get_length_sqrd(),
			self.dot(z_vector)/z_vector.get_length_sqrd())
 
	def __getstate__(self):
		return [self.x, self.y, self.z]
		
	def __setstate__(self, dict):
		self.x, self.y, self.z = dict
		
########################################################################
## Unit Testing														  ##
########################################################################
if __name__ == "__main__":
 
	import unittest
	import pickle
 
	####################################################################
	class UnitTestVec3d(unittest.TestCase):
	
		def setUp(self):
			pass
		
		def testCreationAndAccess(self):
			v = Vec3d(111,222,333)
			self.assert_(v.x == 111 and v.y == 222 and v.z == 333)
			v.x = 333
			v[1] = 444
			v.z = 555
			self.assert_(v[0] == 333 and v[1] == 444 and v[2] == 555)
 
		def testMath(self):
			v = Vec3d(111,222,333)
			self.assertEqual(v + 1, Vec3d(112,223,334))
			self.assert_(v - 2 == [109,220,331])
			self.assert_(v * 3 == (333,666,999))
			self.assert_(v / 2.0 == Vec3d(55.5, 111, 166.5))
			self.assert_(v / 2 == (55, 111, 166))
			self.assert_(v ** Vec3d(2,3,2) == [12321, 10941048, 110889])
			self.assert_(v + [-11, 78, 67] == Vec3d(100, 300, 400))
			self.assert_(v / [11,2,9] == [10,111,37])
 
		def testReverseMath(self):
			v = Vec3d(111,222,333)
			self.assert_(1 + v == Vec3d(112,223,334))
			self.assert_(2 - v == [-109,-220,-331])
			self.assert_(3 * v == (333,666,999))
			self.assert_([222,999,666] / v == [2,4,2])
			self.assert_([111,222,333] ** Vec3d(2,3,2) == [12321, 10941048, 110889])
			self.assert_([-11, 78,67] + v == Vec3d(100, 300, 400))
 
		def testUnary(self):
			v = Vec3d(111,222,333)
			v = -v
			self.assert_(v == [-111,-222,-333])
			v = abs(v)
			self.assert_(v == [111,222,333])
 
		def testLength(self):
			v = Vec3d(1,4,8)
			self.assert_(v.length == 9)
			self.assert_(v.get_length_sqrd() == 81)
			self.assert_(v.normalize_return_length() == 9)
			self.assert_(v.length == 1)
			v.length = 9
			self.assert_(v == Vec3d(1,4,8))
			v2 = Vec3d(10, -2, 12)
			self.assert_(v.get_distance(v2) == (v - v2).get_length())
			
		def testAngles(self):			 
			v = Vec3d(0, 3, -3)
			self.assertEquals(v.angle_around_y, 180)
			self.assertEquals(v.angle_around_x, -45)
			self.assertEquals(v.angle_around_z, 90)
 
			v2 = Vec3d(v)
			v.rotate_around_x(-90)
			self.assertEqual(v.get_angle_between(v2), 90)
 
			v = Vec3d(v2)
			v.rotate_around_y(-90)
			self.assertAlmostEqual(v.get_angle_between(v2), 60)
 
			v = Vec3d(v2)
			v.rotate_around_z(-90)
			self.assertAlmostEqual(v.get_angle_between(v2), 60)
 
			v2.angle_around_z -= 90
			self.assertEqual(v.length, v2.length)
			self.assertEquals(v2.angle_around_z, 0)
			self.assertEqual(v2, [3, 0, -3])
			self.assert_((v - v2).length < 0.00001)
			self.assertEqual(v.length, v2.length)
			v2.rotate_around_y(300)
			self.assertAlmostEquals(v.get_angle_between(v2), 60)
			v2.rotate_around_y(v2.get_angle_between(v))
			angle = v.get_angle_between(v2)
			self.assertAlmostEquals(v.get_angle_between(v2), 0)	 
 
		def testHighLevel(self):
			basis0 = Vec3d(5.0, 0, 0)
			basis1 = Vec3d(0, .5, 0)
			basis2 = Vec3d(0, 0, 3)
			v = Vec3d(10, 1, 6)
			self.assert_(v.convert_to_basis(basis0, basis1, basis2) == [2, 2, 2])
			self.assert_(v.projection(basis0) == (10, 0, 0))
			self.assert_(basis0.dot(basis1) == 0)
			
		def testCross(self):
			lhs = Vec3d(1, .5, 3)
			rhs = Vec3d(4, 6, 1)
			self.assert_(lhs.cross(rhs) == [-17.5, 11, 4])
			
		def testComparison(self):
			int_vec = Vec3d(3, -2, 4)
			flt_vec = Vec3d(3.0, -2.0, 4.0)
			zero_vec = Vec3d(0, 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, 4))
			self.assert_(int_vec != [0, 0, 0])
			self.assert_(int_vec != 5)
			self.assert_(int_vec != [3, -2, 4, 15])
		
		def testInplace(self):
			inplace_vec = Vec3d(5, 13, 17)
			inplace_ref = inplace_vec
			inplace_src = Vec3d(inplace_vec)
			inplace_vec *= .5
			inplace_vec += .5
			inplace_vec /= (3, 6, 9)
			inplace_vec += Vec3d(-1, -1, -1)
			alternate = (inplace_src*.5 + .5)/Vec3d(3, 6, 9) + [-1, -1, -1]
			self.assertEquals(inplace_vec, inplace_ref)
			self.assertEquals(inplace_vec, alternate)
		
		def testPickle(self):
			testvec = Vec3d(5, .3, 8.6)
			testvec_str = pickle.dumps(testvec)
			loaded_vec = pickle.loads(testvec_str)
			self.assertEquals(testvec, loaded_vec)
	
	####################################################################
	unittest.main()
 
	######################################################################## 

I found this on the PyGame website a long time ago, I can't find the link now.