private Vector4 GetWeights(float altitude) { Vector4 weights = new Vector4(1); weights.X = MathUtil.Clamp((-altitude + 40) / 20, 0, 1); weights.Y = MathUtil.Clamp(Math.Abs(altitude - 75) / 40, 0, 1); weights.Z = MathUtil.Clamp(Math.Abs(altitude - 175) / 80, 0, 1); weights.W = MathUtil.Clamp((altitude - 350) / 50, 0, 1); weights.Normalize(); return(weights); }