public class RotaryBarrier
{
  private Vector2D Pos;   //The actual position of the barier
  
  private float Orient;   //Orientation of the whole thing
  private float in_r;     //Radius of the inner circle before extrusion
  private float ext;      //Extrusion Distance beyond the inner circle

  private int numSides; //probably some number from 3 to 10 or so - undefined below 3
  private int MaxSides;
  private int MinSides;

  public LineSeg2D[] lines;
  
  RotaryBarrier()
  { 
    //Basic default values
    MinSides = 3;
    MaxSides = 20;

    numSides = 3;
    Orient = 0;   //0 radians is Right-facing
    in_r = 70;
    ext = 40;

    Pos = new Vector2D(0,0);    
    lines = new LineSeg2D[MaxSides];  //storage for the Line Seg data
    for (int i=0; i<MaxSides; ++i)
    {
      lines[i] = new LineSeg2D();
    }
    
    RecalculateSegs();  //so that we start in a valid state
  }
  
  public int GetNumSides()
  {
    return numSides;
  }

  public int SetNumSides(int i)
  {
    if (i < MinSides)
      numSides = MinSides;
    else if (i > MaxSides)
      numSides = MaxSides;
    else
      numSides = i;
      
    RecalculateSegs();  //refresh our segments  
    return numSides;
  }  
  
  public float GetOrientation()
  {
    return Orient;
  }
  
  public void SetOrientation(float o)
  {
    Orient = o;
    RecalculateSegs();
  }
  
  public Vector2D GetPosition()
  {
    return new Vector2D(Pos);
  }
  
  public void SetPosition(Vector2D v)
  {
    Pos.Set(v);
    RecalculateSegs();
  }
  
  public void SetPosition(float x, float y)
  {
    Pos.Set(x,y);
    RecalculateSegs();
  }
  
  //maybe this should be private
  public void RecalculateSegs()
  {
     //ok, so loop through the sucker, calculating where the Line Seg points are.
     float twopi = 6.283185307f;
     float thetaSep = twopi/numSides;
     Vector2D[] points = new Vector2D[numSides];  //These represent points on the inner circle
     
     float thetaDist = Orient;  //start calculating the points from the original Orientation
     for (int i=0; i<numSides; ++i)
     { 
       points[i] = new Vector2D(in_r*Math.cos(thetaDist),in_r*Math.sin(thetaDist));
       //points[i].Set(in_r*Math.cos(thetaDist),in_r*Math.sin(thetaDist));
       thetaDist += thetaSep;  //increment the Angle to calculate the next point
//       System.out.println("ping\n");       
     }
     
     //Set all but the final line seg, which is special since it links back to the first
     for (int i=0; i<numSides-1; ++i)
     {
       //lines[i].SetP1(points[i]);
       //lines[i].SetP2(points[i+1]);
       
       //This should give us a normalized vector in between the two points
       Vector2D extVect = (points[i].Plus(points[i+1])).retNormalize();
       
       // P1 = p[i]+Extrusion + CenterPoint
       // P2 = p[i+i]+ ditto
       lines[i].SetP1((points[i].Plus(extVect.Times(ext)).Plus(Pos)));
       lines[i].SetP2((points[i+1].Plus(extVect.Times(ext)).Plus(Pos)));       
     }
     //Set the final LineSeg
     Vector2D extVect = (points[points.length-1].Plus(points[0])).retNormalize();
     lines[numSides-1].SetP1((points[points.length-1].Plus(extVect.Times(ext)).Plus(Pos)));
     lines[numSides-1].SetP2((points[0].Plus(extVect.Times(ext)).Plus(Pos)));            
     
  }
  
};