import java.awt.*;
import java.awt.event.*;
import java.util.*;  

public class Dtriangle implements java.io.Serializable{

  InsertionP p1;
  InsertionP p2;
  InsertionP p3;
  Vedge vedge; 
  DoubleVector circum;
  double radius;   
  public Dtriangle(Vedge e1, Vedge e2, Vedge e3){
    Update(e1,e2,e3);
  }
  public Dtriangle(Vector edges, Vedge e[]){
    Update(e[0],e[1],e[2]);
    for(int tn=0;tn<3;tn++)
      edges.addElement(e[tn]);
  }
  
  public Dtriangle(Vector edges, Vedge e1, Vedge e2, Vedge e3){
    Update(e1,e2,e3);
    edges.addElement(e1);
    edges.addElement(e2);
    edges.addElement(e3);
  }
  public void Update(Vedge e1, Vedge e2, Vedge e3){
    
      vedge = e1;
      e1.enext = e2;
      e2.enext = e3;
      e3.enext = e1;
      e1.tri = this;
      e2.tri = this;
      e3.tri = this;
      p1 = vedge.p1;
      p2 = vedge.p2;
      p3 = next(vedge).p2;
      this.setCircumCircle();
  }
  public boolean inCircumCircle(InsertionP ds){ 
    if(ds.Distance(circum.x,circum.y) < radius){
      return true;
    }else{
      return false;
    }
  }
  public void RemoveEdges(Vector edges){
      edges.removeElement(vedge);
      edges.removeElement(next(vedge));
      edges.removeElement(next(next(vedge)));
    }
  private void setCircumCircle(){
    /* see http://mathworld.wolfram.com/Circumcircle.html */
    double a = (p2.y-p3.y)*(p2.x-p1.x)-(p2.y-p1.y)*(p2.x-p3.x);
    double dd = (p1.x+p2.x)*(p2.x-p1.x)+(p2.y-p1.y)*(p1.y+p2.y);
    double df = (p2.x+p3.x)*(p2.x-p3.x)+(p2.y-p3.y)*(p2.y+p3.y);
    circum = new DoubleVector(0.0,0.0);
    if(a==0.0){
      circum.x = 0.0;
      circum.y = 0.0;
      radius = 0.0;
      System.out.println("Error !! in setCircumCircle");
    }
    circum.x = ((dd*(p2.y-p3.y)-df*(p2.y-p1.y))/a/2.0);
    circum.y = ((df*(p2.x-p1.x)-dd*(p2.x-p3.x))/a/2.0);
    radius = (vedge.p1).Distance(circum.x,circum.y);
  }
  private Vedge next(Vedge dv){
    return (dv.enext);
  }
}