/****************************************************************************
* 
* Copyright (c) 2006 by JIA Pei, all rights reserved.
* Copyright (c) 2006 by Vision Open: http://www.visionopen.com/
*
* Author:      	JIA Pei
* Contact:     	jp4work@gmail.com
* URL:		http://www.visionopen.com/members/jiapei.php
* The author administrates Vision Open -- http://www.visionopen.com
*
* This program is free software; you can redistribute it and/or modify it 
* under the terms of the GNU General Public License as published by the 
* Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but 
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 
* for more details.
* 
* You should have received a copy of the GNU General Public License along 
* with this program; if not, write to the Free Software Foundation, Inc., 
* 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
* 
* This software is partly based on the following open source: 
*  
*		- Boost 
*		- OpenCV 
* 
* This software is using IMM Face Database, which can be downloaded from
* http://www2.imm.dtu.dk/~aam/.
*
* M. B. Stegmann, B. K. Ersb{\o}ll, and R. Larsen. FAME - a flexible appearance 
* modelling environment. IEEE Trans. on Medical Imaging, 22(10):1319-1331, 2003
*
****************************************************************************/

// $Id: lv_triangle2d.h,v 1.1.1.1 2006-09-03 17:49:04 JIA Pei Exp $ 

#ifndef __lv_triangle2d__
#define __lv_triangle2d__

#include <vector>

#include "cv.h"
#include "highgui.h"

using namespace std;


class lv_triangle2d
{
public:

    // Positions of 3 triangle vertexes
    vector<CvPoint2D32f>    m_vVertexes;

    double                  m_dD;

    lv_triangle2d() {this->m_vVertexes.resize (3); this->m_dD = 0;}

    lv_triangle2d(const vector<CvPoint2D32f> &iVertexes)
    {
        assert (iVertexes.size () == 3);
        this->m_vVertexes.clear ();
        this->m_vVertexes = iVertexes;
        this->m_dD = this->Calc_dD ();
    }

    lv_triangle2d(const CvMat* iVertexes)
    {
        assert (iVertexes->cols == 3);
        this->m_vVertexes.resize (3);
        for (unsigned int i = 0; i < this->m_vVertexes.size (); i++)
        {
            this->m_vVertexes[i] = CV_MAT_ELEM( *iVertexes, CvPoint2D32f, 0, i );
        }
        this->m_dD = this->Calc_dD ();
    }

    ~lv_triangle2d() {this->m_vVertexes.clear(); }

    double Calc_dD()
    {
        double x1, x2, x3, y1, y2, y3;

        x1 = this->m_vVertexes[0].x;
        x2 = this->m_vVertexes[1].x;
        x3 = this->m_vVertexes[2].x;
        y1 = this->m_vVertexes[0].y;
        y2 = this->m_vVertexes[1].y;
        y3 = this->m_vVertexes[2].y;

        return (+x2*y3-x2*y1-x1*y3-x3*y2+x3*y1+x1*y2);
    }

    // operators
    lv_triangle2d&           operator=(const lv_triangle2d &s)
    {
        this->m_vVertexes   = s.m_vVertexes;
        this->m_dD          = s.m_dD;
        return (*this);
    }
};



#endif  // __lv_triangle2d__