def test_slerp():
a = Quaternion(x, y, z, w)
b = Quaternion(-x, -y, -z, -w)
c = a.clone().slerp(b, 0)
d = a.clone().slerp(b, 1)
assert a.equals(c), "Passed"
assert b.equals(d), "Passed"
sqrt1_2 = sqrt(1 / 2)
e = Quaternion(1, 0, 0, 0)
f = Quaternion(0, 0, 1, 0)
expected = Quaternion(sqrt1_2, 0, sqrt1_2, 0)
result = e.clone().slerp(f, 0.5)
assert abs(result.x - expected.x) <= eps, "Check x"
assert abs(result.y - expected.y) <= eps, "Check y"
assert abs(result.z - expected.z) <= eps, "Check z"
assert abs(result.w - expected.w) <= eps, "Check w"
g = Quaternion(0, sqrt1_2, 0, sqrt1_2)
h = Quaternion(0, -sqrt1_2, 0, sqrt1_2)
expected = Quaternion(0, 0, 0, 1)
result = g.clone().slerp(h, 0.5)
assert abs(result.x - expected.x) <= eps, "Check x"
assert abs(result.y - expected.y) <= eps, "Check y"
assert abs(result.z - expected.z) <= eps, "Check z"
assert abs(result.w - expected.w) <= eps, "Check w"
def test_equals():
a = Quaternion(x, y, z, w)
b = Quaternion(-x, -y, -z, -w)
assert a.x != b.x
assert a.y != b.y
assert not a.equals(b)
assert not b.equals(a)
a.copy(b)
assert a.x == b.x
assert a.y == b.y
assert a.equals(b)
assert b.equals(a)
def test_rotate_towards():
a = Quaternion()
b = Quaternion().set_from_euler(Euler(0, pi, 0))
c = Quaternion()
half_pi = pi * 0.5
a.rotate_towards(b, 0)
assert a.equals(a) is True
a.rotate_towards(b, pi * 2)
# test overshoot
assert a.equals(b) is True
a.set(0, 0, 0, 1)
a.rotate_towards(b, half_pi)
assert a.angle_to(c) - half_pi <= eps
def test_set_from_axis_angle():
# TODO: find cases to validate.
# assert True
zero = Quaternion()
a = Quaternion().set_from_axis_angle(Vector3(1, 0, 0), 0)
assert a.equals(zero)
a = Quaternion().set_from_axis_angle(Vector3(0, 1, 0), 0)
assert a.equals(zero)
a = Quaternion().set_from_axis_angle(Vector3(0, 0, 1), 0)
assert a.equals(zero)
b1 = Quaternion().set_from_axis_angle(Vector3(1, 0, 0), pi)
assert not a.equals(b1)
b2 = Quaternion().set_from_axis_angle(Vector3(1, 0, 0), -pi)
assert not a.equals(b2)
b1.multiply(b2)
assert a.equals(b1)