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qsprojection.h

/***************************************************************************
                                qsprojection.h
                             -------------------                                         
    begin                : 01-January-2000
    copyright            : (C) 2000 by Kamil Dobkowski                         
    email                : kamildobk@poczta.onet.pl                                     
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   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; either version 2 of the License, or     *
 *   (at your option) any later version.                                   * 
 *                                                                         *
 ***************************************************************************/


#ifndef QSPROJECTION_H
#define QSPROJECTION_H

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include"qscoord.h"
#include"qsgattr.h"

class QSAxes;
class QSProjection {
 public:
    static const double pi;
     static inline double degToRad( double deg ) { return deg*pi/180.0; }
     static inline double radToDeg( double rad ) { return rad*180.0/pi; }
    enum ClipResult { Rejected = 0, Clipped, Accepted };
    QSProjection();
    virtual ~QSProjection();
    virtual void setLight( bool enabled );
    virtual void setLightParameters( const QSPt3f& lightVector, int ambientLight, int directedLight );
    bool light() const { return m_light; }
    QSPt3f lightVector() const { return m_light_vector; }
    int ambientLight() const { return m_ambient_light; }
    int directedLight() const { return m_directed_light; }
    virtual QSPt3f world2DToCanvas3( const QSPt2f& p ) const = 0;
    virtual QSPt2f world2DToCanvas( const QSPt2f& p ) const = 0;
    virtual QSPt3f world3DToCanvas3( const QSPt3f &p ) const = 0;
    virtual QSPt2f world3DToCanvas( const QSPt3f &p ) const = 0;
    virtual QSPt3f canvas3ToWorld3D( const QSPt3f &p ) const = 0;
    QSPt2f map( const QSPt3f& pos ) const { return QSPt2f( pos.x, pos.y ); }
    QSPt3f map( const QSPt2f& pos ) const { return QSPt3f( pos.x, pos.y, 0.0 ); }
    virtual QSPt3f furthest() const;
    virtual QSPt2f middle() const;
    virtual ClipResult clipPoint2( const QSPt2f& p1 ) const;
    virtual ClipResult clipLine2( QSPt2f* p1, QSPt2f* p2 ) const;
    virtual ClipResult clipPoly2( const QSPt2f in[], int inpoints, QSPt2f out[], int *outpoints, int maxout,  bool outedges[] = NULL, const bool inedges[] = NULL ) const;
    virtual ClipResult clipPoint3( const QSPt3f& pos ) const;
    virtual ClipResult clipLine3( QSPt3f* p1, QSPt3f* p2 ) const;
     virtual ClipResult clipPoly3( const QSPt3f in[], int inpoints, QSPt3f out[], int *outpoints, int maxpoints, const QSPt3f cube[2],  bool outedges[] = NULL, const bool inedges[] = NULL ) const;
     virtual void shade( QSGFill &fill, const QSPt3f& normal, const QSPt2f* canvas_pts, int npoints, QSGFill *bottomFill ) const;

 //-----------------------------------------------------------------------------------------------------//

    static bool pointInPoly( const QSPt2f& pos, const QSPt2f* pts, int npts );

 //-----------------------------------------------------------------------------------------------------//
    
      static double dotProduct( const QSPt3f& p1, const QSPt3f& p2 );
      static QSPt3f vectorProduct( const QSPt3f& p1, const QSPt3f& p2 );
      static QSPt3f normal( const QSPt3f vertices[4], bool normalize = true );
      static QSPt3f normal( const QSPt3f *v, int npoints, bool normalize = true );
      static QSPt3f normalize( QSPt3f vector );
     static void getPoly3Cube( const QSPt3f in[], int inpoints, QSPt3f cube[2] );
     static ClipResult clipLine( QSPt2f* p0, QSPt2f* p1, const QSPt2f& clip_pos, const QSPt2f& clip_area );
     static void clipVertexNormals( const QSPt3f in[], int inpoints, const QSPt3f clip[], int clipoints, const QSPt3f innors[], QSPt3f outnor[] );
     static void clipVertexColors( const QSPt3f in[], int inpoints, const QSPt3f clip[], int clipoints, const QSGFill incol[], QSGFill outcol[] );
     static bool isBottom( const QSPt2f pts[], int npoints );
    static bool isBottom( const QSPt3f pts[], int npoints );
    static inline bool isBottom( const QSPt3f &p0,const QSPt3f &p1, const QSPt3f &p2 ) {
             return 0.0 > p2.x*p0.y - p0.x*p2.y + p0.x*p1.y - p1.x*p0.y + p1.x*p2.y - p2.x*p1.y;
        }
    static bool isFlat( const QSPt3f pts[], int npoints );
    static bool isCorrect( const QSPt3f pts[4] );
    static bool isCorrect( const double values[4] );
    /*
     * Extracs triangle from polygon. This methods divides polygon into npoints-2 triangles.
     */
      static void triangulate1( int triangleNumber, const QSPt3f pts[], int npoints, QSPt3f triangle[3], bool edges[3] );

   protected:
    bool m_light;
    QSPt3f m_light_vector;
    int m_ambient_light;
    int m_directed_light;

   private:
       static QSPt3f  interpolation( const QSPt3f& p1, const QSPt3f& p2, double t );
       static QSGFill interpolation( const QSGFill& f1, const QSGFill& f2, double t );
       static void get_interpolation_params(const QSPt3f in[], int inpoints, const QSPt3f& clip, int p1[2], int p2[2], double *t1, double *t2, double *t3 );
 };

#endif

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