/* *  Stage : a multi-robot simulator. *  Copyright (C) 2001, 2002 Richard Vaughan, Andrew Howard and Brian Gerkey. * *  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. * *  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 */// ==================================================================// Filename:	raytrace.hh// $Id: raytrace.hh,v 1.2 2002/11/01 19:12:30 rtv Exp $// RTV// ==================================================================#ifndef RAYTRACE_HH#define RAYTRACE_HH#include <math.h>#include "matrix.hh"#include "world.hh"enum LineIteratorMode { PointToPoint=0, PointToBearingRange };// these classes do not inherit from each other, but they have similar// interfaces and use each other extensively// scans the points along a lineclass CLineIterator{ private:  double m_x, m_y;    double m_remaining_range;  double m_max_range;  double m_angle;    CEntity** m_ent;  int m_index;  double m_ppm;  CMatrix* m_matrix; public:  CLineIterator( double x, double y, double a, double b, 		 double ppm, CMatrix* matrix, LineIteratorMode pmode );    CEntity* GetNextEntity( void );  inline void GetPos( double& x, double& y )    {      x = m_x / m_ppm;      y = m_y / m_ppm;    };    inline double GetRange( void )    {      return( (m_max_range - m_remaining_range) / m_ppm );    };  inline double GetAngle( void )  {    return( m_angle );  };  inline CEntity** RayTrace( double &px, double &py, double pth, 			     double &remaining_range );  void PrintArray( CEntity** ent );  };// scans the AREA of a triangleclass CTriangleAreaIterator{private:  double m_x, m_y;    double m_bearing;  double m_range_so_far;  double m_max_range;  double m_angle;  double m_skip;    double m_li_angle;  double m_ppm;  CMatrix* m_matrix;  CLineIterator* li; // we use LineIterators to do the work public:  // an isoceles triangle is specified from it's point, by the bearing  // and length of it's left side, and by the angle between the equal  // sides. the triangle is scanned from point to base in increasingly  // long lines perpendicular to the base. skip give the distance  // increment between scan lines.  CTriangleAreaIterator( double x, double y, 			 double bearing, double range, double angle,			 double skip,			 double ppm, CMatrix* matrix );    ~CTriangleAreaIterator();  CEntity* GetNextEntity( void );//    inline void GetPos( double& x, double& y )//      {//        x = m_x / m_ppm;//        y = m_y / m_ppm;//      };    double GetRange( void );  //void PrintArray( CEntity** ent ); };// scans an arc of a circleclass CArcIterator{protected:  double m_radius;  double m_px, m_py;  double m_center_x, m_center_y;  double m_angle;  double m_dangle;  double m_max_angle;  int m_index;  CEntity** m_ent;  double m_ppm;  CMatrix* m_matrix; public:  CArcIterator( double x, double y, double th,  double scan_r, double scan_th,		   double ppm, CMatrix* matrix );      inline CEntity** ArcTrace( double &remaining_angle );    CEntity* GetNextEntity( void );  void PrintArray( CEntity** ent );  inline void GetPos( double& x, double& y )    {      x = m_px / m_ppm;      y = m_py / m_ppm;    };    inline double GetRange( void )    {      return( hypot( m_px - m_center_x, m_py - m_center_y ) / m_ppm );    };  inline double GetAngle( void )  {    return( m_angle );  };  };// a circle iterator is an arc iterator with a hard-coded 2*PI max_angle class CCircleIterator : public CArcIterator{public:   CCircleIterator( double x, double y, double r, 		   double ppm, CMatrix* matrix );};class CRectangleIterator{ private:  CLineIterator* lits[4];   double corners[4][2];   public:  CRectangleIterator( double x, double y, double th,		      double w, double h,  		      double ppm, CMatrix* matrix );  ~CRectangleIterator( void );   CEntity* GetNextEntity( void );       inline void GetPos( double& x, double& y )  {    for( int i=0; i<4; i++ )      if( lits[i] != 0 ) // find the current line iterator	{	  lits[i]->GetPos( x, y );	  break;	}  };};// given a pointer to an array of entity pointers, this iterator will// return one entity* at a time. when it runs out of entities, it// returns null.class CDatabaseIterator{private:  CEntity** database;  int index;  int len;public:  CDatabaseIterator( CEntity** database, int len )  {    this->database = database;    this->len = len;    index = 0;  };  CEntity* GetNextEntity( void )  {    if( index < len )      return database[index++];    else      return (CEntity*)0;  }};#endif // RAYTRACE_HH