//! multiplication operator by a vector
public static Vector3D operator *(Vector3D lhs, Quaternion rhs)
{
Vector3D qvec = new Vector3D(rhs.X, rhs.Y, rhs.Z);
Vector3D uv = qvec.CrossProduct(lhs);
Vector3D uuv = qvec.CrossProduct(uv);
uv *= (2.0f * rhs.W);
uuv *= 2.0f;
return lhs + uv + uuv;
}
/// <summary> Builds a right-handed look-at matrix.</summary>
public void BuildCameraLookAtMatrixRH(Vector3D position, Vector3D target, Vector3D upVector)
{
Vector3D zaxis = position - target;
zaxis.Normalize();
Vector3D xaxis = upVector.CrossProduct(zaxis);
xaxis.Normalize();
Vector3D yaxis = zaxis.CrossProduct(xaxis);
SetMInsecure(0, 0, xaxis.X);
SetMInsecure(1, 0, yaxis.X);
SetMInsecure(2, 0, zaxis.X);
SetMInsecure(3, 0, 0);
SetMInsecure(0, 1, xaxis.Y);
SetMInsecure(1, 1, yaxis.Y);
SetMInsecure(2, 1, zaxis.Y);
SetMInsecure(3, 1, 0);
SetMInsecure(0, 2, xaxis.Z);
SetMInsecure(1, 2, yaxis.Z);
SetMInsecure(2, 2, zaxis.Z);
SetMInsecure(3, 2, 0);
SetMInsecure(0, 3, -xaxis.DotProduct(position));
SetMInsecure(1, 3, -yaxis.DotProduct(position));
SetMInsecure(2, 3, -zaxis.DotProduct(position));
SetMInsecure(3, 3, 1.0f);
}