public void QuaternionLerpTest1()
{
Vector3 axis = Vector3.Normalize(new Vector3(1.0f, 2.0f, 3.0f));
Quaternion a = Quaternion.CreateFromAxisAngle(axis, MathHelper.ToRadians(10.0f));
Quaternion b = Quaternion.CreateFromAxisAngle(axis, MathHelper.ToRadians(30.0f));
Single t = 0.0f;
Quaternion expected = new Quaternion(a.X, a.Y, a.Z, a.W);
Quaternion actual = Quaternion.Lerp(a, b, t);
Assert.True(MathHelper.Equal(expected, actual), $"Quaternion.Lerp did not return the expected value: expected {expected} actual {actual}");
}
public void QuaternionLerpTest3()
{
Vector3 axis = Vector3.Normalize(new Vector3(1.0f, 2.0f, 3.0f));
Quaternion a = Quaternion.CreateFromAxisAngle(axis, MathHelper.ToRadians(10.0f));
Quaternion b = Quaternion.Negate(a);
Single t = 1.0f;
Quaternion actual = Quaternion.Lerp(a, b, t);
// Note that in quaternion world, Q == -Q. In the case of quaternions dot product is zero,
// one of the quaternion will be flipped to compute the shortest distance. When t = 1, we
// expect the result to be the same as quaternion b but flipped.
Assert.True(actual == a, $"Quaternion.Lerp did not return the expected value: expected {a} actual {actual}");
}
public void QuaternionLerpTest()
{
Vector3 axis = Vector3.Normalize(new Vector3(1.0f, 2.0f, 3.0f));
Quaternion a = Quaternion.CreateFromAxisAngle(axis, MathHelper.ToRadians(10.0f));
Quaternion b = Quaternion.CreateFromAxisAngle(axis, MathHelper.ToRadians(30.0f));
Single t = 0.5f;
Quaternion expected = Quaternion.CreateFromAxisAngle(axis, MathHelper.ToRadians(20.0f));
Quaternion actual;
actual = Quaternion.Lerp(a, b, t);
Assert.True(MathHelper.Equal(expected, actual), $"Quaternion.Lerp did not return the expected value: expected {expected} actual {actual}");
// Case a and b are same.
expected = a;
actual = Quaternion.Lerp(a, a, t);
Assert.True(MathHelper.Equal(expected, actual), $"Quaternion.Lerp did not return the expected value: expected {expected} actual {actual}");
}