public static double RotationAnglesSum(this Matrix4d r) { Vector3d v = r.RotationAngles(); System.Diagnostics.Debug.WriteLine("--Rotation: " + v.X.ToString("0.00") + " : " + v.Y.ToString("0.00") + " : " + v.Z.ToString("0.00") + " : "); return(v.X + v.Y + v.Z); }