#ifndef __RECTANGLE3_H
#define __RECTANGLE3_H

#include <iostream>
using namespace std;
#include "Vector3.h"

namespace GtpVisibilityPreprocessor {

/// rectangle vertices
//   3 2
//   0 1
class Rectangle3 {
public:
  Vector3 mVertices[4];

  inline Vector3 GetVertex(const int i) const { return mVertices[i]; }
  Rectangle3() {}
  
  Rectangle3(const Vector3 &v0,
	     const Vector3 &v1,
	     const Vector3 &v2,
	     const Vector3 &v3) {
    mVertices[0] = v0;
    mVertices[1] = v1;
    mVertices[2] = v2;
    mVertices[3] = v3;
  }
  
  Vector3 GetNormal() const {
    return Normalize(CrossProd(mVertices[0]-mVertices[1],
			       mVertices[2]-mVertices[1]
			       ));
  }
  
  Vector3 GetCenter() const {
    return (mVertices[0] + mVertices[1] + mVertices[2] + mVertices[3])/4.0f;
  }

  int DominantAxis() const {
    if (SqrMagnitude(mVertices[0] - mVertices[1]) >  SqrMagnitude(mVertices[0] - mVertices[3]))
      return 0;
    else
      return 1;
  }
      
  float GetArea() const {
    Vector3 v = CrossProd(mVertices[3], mVertices[0]);
    
    for (int i=0; i < 3; i++)
      v += CrossProd(mVertices[i], mVertices[i+1]);
    
    return 0.5f*abs(DotProd(GetNormal(), v));
  }
  
  void
  Split(const int axis,
	Rectangle3 &r1,
	Rectangle3 &r2
	) const;

  friend ostream& operator<< (ostream &s, const Rectangle3 &r) {
    return s<<"Rectangle3:"<<r.mVertices[0]<<r.mVertices[1]<<r.mVertices[2]<<r.mVertices[3];
  }

};

}

#endif