//##################################################################################################
//
//   Custom Visualization Core library
//   Copyright (C) 2011-2013 Ceetron AS
//
//   This library may be used under the terms of either the GNU General Public License or
//   the GNU Lesser General Public License as follows:
//
//   GNU General Public License Usage
//   This library 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, either version 3 of the License, or
//   (at your option) any later version.
//
//   This library 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 at <<http://www.gnu.org/licenses/gpl.html>>
//   for more details.
//
//   GNU Lesser General Public License Usage
//   This library is free software; you can redistribute it and/or modify
//   it under the terms of the GNU Lesser General Public License as published by
//   the Free Software Foundation; either version 2.1 of the License, or
//   (at your option) any later version.
//
//   This library 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 Lesser General Public License at <<http://www.gnu.org/licenses/lgpl-2.1.html>>
//   for more details.
//
//##################################################################################################


#pragma once

#include "cvfObject.h"
#include "cvfVector3.h"
#include "cvfMatrix4.h"
#include "cvfArray.h"

namespace external {
namespace cvf {

//=================================================================================================
// 
// Plane class
// 
//=================================================================================================
class Plane : public Object
{
public:
    enum Side { FRONT, BACK, ON, BOTH };

public:
    Plane();
    Plane(double A, double B, double C, double D);
    Plane(const Plane& other);
    ~Plane();

    const Plane&    operator=(const Plane& other);
    bool            operator==(const Plane& other) const;
    bool            operator!=(const Plane& other) const;

    inline double   A() const   { return m_A; }     ///< Get plane coefficient A
    inline double   B() const   { return m_B; }     ///< Get plane coefficient B     
    inline double   C() const   { return m_C; }     ///< Get plane coefficient C
    inline double   D() const   { return m_D; }     ///< Get plane coefficient D

    bool            isValid() const;

    void            set(double A, double B, double C, double D);
    bool            setFromPointAndNormal(const Vec3d& point, const Vec3d& normal);
    bool            setFromPoints(const Vec3d& p1, const Vec3d& p2, const Vec3d& p3);

    Vec3d           normal() const;
    Vec3d           pointInPlane() const;

    void            flip();
    void            transform(const Mat4d& matrix);

    double          distance(const Vec3d& point) const;
    double          distanceSquared(const Vec3d& point) const;
    double          distanceToOrigin() const;

    bool            projectVector(const Vec3d& vector, Vec3d* projectedVector) const;
    Vec3d           projectPoint(const Vec3d& point) const;

    bool            intersect(const Plane& other, Vec3d* point, Vec3d* direction = NULL) const;
    bool            intersect(const Vec3d& a, const Vec3d& b, Vec3d* intersection) const;
    size_t          clipTriangle(const Vec3d& ta, const Vec3d& tb, const Vec3d& tc, Vec3d clippedPolygon[4]) const;
    
    Side            side(const Vec3d& point) const;
    Side            side(const Vec3dArray& points) const;

private:
    double m_A;     // Plane equation coefficients
    double m_B;     //
    double m_C;     //
    double m_D;     //
};

}
} //namespace external
