#ifndef IPolyg2_HH
#define IPolyg2_HH
////////////////////////////////////////////////////////////////////////
//! file="amma/Geometry/CmpGeo2d/IPolyg2.hh"
//! lib=Mcg2
//! userlevel=Normal
//! author="Radek Marik"
//! docentry="Geometry.2-D"
//! date="20.12.1994"
//! rcsid="$Id: IPolyg2.hh,v 1.9 1999/10/11 12:22:24 ees1cg Exp $"

#include "amma/StdType.hh"
#include "amma/Index2d.hh"
#include "amma/DList.hh"
#include "amma/EdgeList.hh"

class istream;
class ostream;
class IntRectangleTPC;

typedef DListC<Index2dC> Index2ListC; 

//====================================================================
//======= IntPolygon2dC ==============================================
//====================================================================

//: An integer polygon in 2d space
// The IntPolygon2dC class is a representation of a polygon in 2 dimensional
// digital space. A polygon is the region of a plane bounded by
// a finite collection of line segments forming a simple closed curve. 

class IntPolygon2dC: private Index2ListC
{
  // ===============
  // == BIG OBJECT =
  // ===============

  public:

    // Type definitions
    // ----------------

    typedef LongIntT AreaT; // polygon area

  public:

    // Constructor, copies, assigment, and destructor
    // ----------------------------------------------

    inline IntPolygon2dC();
    // Empty polygon.
  
    IntPolygon2dC(const IntPolygon2dC & points);
    // Another access to the polygon.

    inline IntPolygon2dC(const Index2ListC & points);
    // Constructs a polygon from a list of points. The 'points' will
    // be shared by the polygon (as a big object).
 
    IntPolygon2dC(const DListC<EdgePtrC> & vertexes);
    // Construct a polygon from a list of vertexes.

    IntPolygon2dC(const DListC<EdgeCPtrC> & vertexes);
    // Construct a polygon from a list of vertexes.

    // Access to the object model
    // --------------------------

    inline const Index2ListC & List() const;
    // Access to the constant list of vertexes.


    // Derived characteristics of the object
    // -------------------------------------

    AreaT Area2() const;
    // Returns twice the signed area of this polygon.
    // Ref.: -  O'Rourke,J.: Computatinal geometry in C;
    //          Cambridge University Press, 1994, pp. 20-26

    IntRectangleTPC MinimumRectangle() const;
    // Returns a minimum enclosing rectangle of this polygon. The polygon
    // must be convex and counter-clockwise oriented.

  private:

    // Special type definitions
    // ------------------------

    typedef RealT DAreaT;  // non-integer area during computation.

  private:

    // Special member functions
    // ------------------------

    inline Index2ListC & MyList();
    // Returns the reference to the list of indexes.

  friend istream & operator>>(istream & s, IntPolygon2dC & pol);
  friend ostream & operator<<(ostream & s, const IntPolygon2dC & pol);
};

istream & 
operator>>(istream & s, IntPolygon2dC & pol);
// Reads a polygon from the input stream.

ostream & 
operator<<(ostream & s, const IntPolygon2dC & pol);
// Sends the polygon into the output stream.

typedef DListC<IntPolygon2dC> FooIntPolygon2dCPPPPPC; // help GNU C++ 2.6.0

void 
SaveAsGF(ostream & s, const DListC<IntPolygon2dC> & pols,
         IntPolygon2dC::AreaT minArea = 0);
// Save all polygons which inside area is bigger than 'minArea'
// into the stream 's'.

//====================================================================
//======= IntPolygon2dC ==============================================
//====================================================================

inline 
const Index2ListC & 
IntPolygon2dC::List() const
//=========================
{
  return(*this);
}

inline 
Index2ListC & 
IntPolygon2dC::MyList()
//=====================
{
  return(*this);
}

inline 
IntPolygon2dC::IntPolygon2dC()
//============================
: Index2ListC()
{}

inline 
IntPolygon2dC::IntPolygon2dC(const Index2ListC & points)
//======================================================
: Index2ListC(points)
{}

#endif

// IAPS - Image analysis program system.
// End of include file IPolyg2.hh