package fb.math{
  public final class Degree{
    //角度转换为弧度
  public static function angleToRadian(angle:Number):Number {
    return angle*(Math.PI/180);
  }
  //弧度转换为角度
  public static function radianToAngle(radian:Number):Number {
    return radian*(180/Math.PI);
  }
  //修正角度在360度以内
  public static function fixAngle(angle:Number):Number {
    return (angle %= 360)<0 ? angle+360 : angle;
  }
  //以角度为单位计算三角函数值
  public static function sinD(angle:Number):Number {
    return Math.sin(angleToRadian(angle));
  }
  public static function cosD(angle:Number):Number {
    return Math.cos(angleToRadian(angle));
  }
  public static function tanD(angle:Number):Number {
    return Math.tan(angleToRadian(angle));
  }
  //返回的值是以角度为单位
  public static function asinD(radian:Number):Number {
    return radianToAngle(Math.acos(radian));
  }
  public static function acosD(radian:Number):Number {
    return radianToAngle(Math.acos(radian));
  }
  public static function atanD(radian:Number):Number {
    return radianToAngle(Math.acos(radian));
  }
  public static function atan2D(y:Number, x:Number):Number {
    return radianToAngle(Math.atan2(y, x));
  }
  }
}