Custom C++ Quaternion Rotation Not Working Correctly

Question

In my code, I have a quaternion that is used for rotation for a camera for the player. Rotation itself seems to work fine, but my directional vectors for moving and to rotate on do not rotate correctly.

Quaternion Multiplication:

Quaternion Quaternion::operator*(Vector3 other) const
{

    float x_ = w * other.x + y * other.z - z * other.y;
    float y_ = w * other.y + z * other.x - x * other.z;
    float z_ = w * other.z + x * other.y - y * other.x;
    float w_ = -x * other.x - y * other.y - z * other.z;

    return Quaternion(x_, y_, z_, w_);

}

Quaternion Quaternion::operator*(Quaternion other) const
{

    Vector4 r = other.getValues();

    float x_ = x * r.w + w * r.x + y * r.z - z * r.y;
    float y_ = y * r.w + w * r.y + z * r.x - x * r.z;
    float z_ = z * r.w + w * r.z + x * r.y - y * r.x;
    float w_ = w * r.w - x * r.x - y * r.y - z * r.z;

    return Quaternion(x_, y_, z_, w_);

}

Conjugate Function

Quaternion Quaternion::conjugate() const
{

    return Quaternion(-x, -y, -z, w);

}

Vector Rotation:

void Vector3::rotate(Quaternion rotation)
{

    Quaternion rotated = rotation * *this * rotation.conjugate();

    x = rotated.getValues().x;
    y = rotated.getValues().y;
    z = rotated.getValues().z;

}

Sample Directional Vector:

Vector3 Quaternion::getRight() const
{

    Vector3 right(1.0f, 0.0f, 0.0f);
    right.rotate(*this);

    return right;

}

If I have the camera rotated exactly 90 degrees around the y-axis and I print out the values of the right vector, x is 0.000796229, y is 0 and z is -1. In this case, x should be 0 and z should be a positive 1.

I have been browsing Google and others' code for the past few days trying to find what I am doing wrong, but I cannot find anything wrong.

UPDATE:

I ended up deciding to just incorporate GLM into my math classes and after some changing of things, everything works as it should.

Answer 1

I ended up deciding to just incorporate GLM into my math classes and after some changing of things, everything works as it should.

Answer 2

In your vector rotation replace the first line by

Quaternion rotated = rotation * Quaternion(this->x, this->y, this->z, 0) * 
    rotation.conjugate();

Explanation: Quaternion multiplications are not commutative, which means that Q * v does not equal v * Q, with v being a Quaternion with w=0.