【Unity】Scriptからambient color変更

Scriptからambient colorを変更する方法(Unity var5.1)
例:ChangeColorを呼ぶたびにランダムでambient colorを変える場合

sample.cs

void ChangeColor(){
     Color colorGreen=new Color(134f,244f,171f,255f);
     Color colorBlue=new Color(134f,140f,244f,255f);
     Color colorRed=new  Color(244f,134f,182f,255f);
     Color colorOrange=new Color(244f,182f,134f,255f);
     Color[] colorList={colorGreen,colorBlue,colorRed,colorOrange};
     int randamColor=Random.Range(0,colorList.Length);
     float sum = colorList[randamColor].r
                       + colorList[randamColor].g 
                      + colorList[randamColor].b;
     float reciprocal = 1/sum;
        colorList[randamColor] = colorList[randamColor]*reciprocal;
        RenderSettings.ambientSkyColor=colorList[randamColor];
    }