public void Update(Vector3 position, Vector3 camPos) { if (!bVisible && alpha > 0f) { Fade(-0.03f); } else if (bVisible && alpha < 1f) { Fade(0.1f); } Vector3 viewNormal = Vector3.Normalize(position - camPos); rotationMatrix = MathExtra.MatrixFromNormal(viewNormal); world = Matrix.CreateScale(drawScale) * rotationMatrix * Matrix.CreateTranslation(position); }