vcglib: segment3.h Source File

00001 /****************************************************************************
00002 * VCGLib                                                            o o     *
00003 * Visual and Computer Graphics Library                            o     o   *
00004 *                                                                _   O  _   *
00005 * Copyright(C) 2004                                                \/)\/    *
00006 * Visual Computing Lab                                            /\/|      *
00007 * ISTI - Italian National Research Council                           |      *
00008 *                                                                    \      *
00009 * All rights reserved.                                                      *
00010 *                                                                           *
00011 * This program is free software; you can redistribute it and/or modify      *   
00012 * it under the terms of the GNU General Public License as published by      *
00013 * the Free Software Foundation; either version 2 of the License, or         *
00014 * (at your option) any later version.                                       *
00015 *                                                                           *
00016 * This program is distributed in the hope that it will be useful,           *
00017 * but WITHOUT ANY WARRANTY; without even the implied warranty of            *
00018 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the             *
00019 * GNU General Public License (http://www.gnu.org/licenses/gpl.txt)          *
00020 * for more details.                                                         *
00021 *                                                                           *
00022 ****************************************************************************/
00023 /****************************************************************************
00024   History
00025 
00026 $Log: not supported by cvs2svn $
00027 Revision 1.7  2006/06/06 14:35:31  zifnab1974
00028 Changes for compilation on linux AMD64. Some remarks: Linux filenames are case-sensitive. _fileno and _filelength do not exist on linux
00029 
00030 Revision 1.6  2006/03/07 16:39:38  pietroni
00031 compiled  and corrected ClosestPoint function
00032 
00033 Revision 1.5  2004/05/13 23:39:47  ponchio
00034 SegmentType -> Segment3 in constructor (g++ complained)
00035 
00036 Revision 1.4  2004/05/08 14:07:50  ganovelli
00037 return type of length and squaredlength corrected
00038 
00039 Revision 1.3  2004/03/11 11:47:20  tarini
00040 minor updates, corrections, added documentations, etc.
00041 
00042 
00043 Revision 1.1  2004/03/08 19:46:47  tarini
00044 First Version (tarini)
00045 
00046 ****************************************************************************/
00047 
00048 
00049 
00050 #ifndef __VCGLIB_SEGMENT3
00051 #define __VCGLIB_SEGMENT3
00052 
00053 #include <vcg/space/point3.h>
00054 #include <vcg/space/line3.h>
00055 #include <vcg/space/box3.h>
00056 
00057 namespace vcg {
00058 
00066 template <class SegmentScalarType >
00067 class Segment3
00068 {
00069 public: 
00070 
00072         typedef SegmentScalarType ScalarType;
00073 
00075         typedef Point3<SegmentScalarType> PointType;
00076 
00078         typedef Segment3<SegmentScalarType> SegmentType;
00079 
00080 private:
00081 
00083         PointType _p0,_p1;
00084 
00085 public:
00086 
00088   inline const PointType &P0() const { return _p0; } 
00089   inline const PointType &P1() const { return _p1; } 
00090   inline PointType &P0() { return _p0; } 
00091   inline PointType &P1() { return _p1; } 
00093         Segment3() {};
00095         Segment3(const PointType &a, const PointType &b) { _p0=a; _p1=b; };
00097         inline bool operator == ( SegmentType const & p ) const
00098         {       return _p0==p._p0 && _p1==p._p1; }
00100         inline bool operator != ( SegmentType const & p ) const
00101         {       return _p0!=p._p0 || _p1!=p._p1; }
00103         void Set( const PointType &a, const PointType &b)
00104         {       _p0=a; _p1=b;}
00107         inline PointType P( const ScalarType t ) const
00108         { return _p0 + (_p1 - _p0) * t; }
00110         inline PointType MidPoint( ) const
00111         { return ( _p0 +  _p1) / ScalarType(2.0) ; }
00113         inline Box3<ScalarType> BBox( ) const
00114         { Box3<ScalarType> t; 
00115           if (_p0[0]<_p1[0]) { t.min[0]=_p0[0];t.max[0]=_p1[0];} else { t.min[0]=_p1[0];t.max[0]=_p0[0];}
00116                 if (_p0[1]<_p1[1]) { t.min[1]=_p0[1];t.max[1]=_p1[1];} else { t.min[1]=_p1[1];t.max[1]=_p0[1];}
00117           if (_p0[2]<_p1[2]) { t.min[2]=_p0[2];t.max[2]=_p1[2];} else { t.min[2]=_p1[2];t.max[2]=_p0[2];}
00118           return t; }
00120         ScalarType Length()
00121         { return (_p0 - _p1).Norm(); }
00123         ScalarType SquaredLength()
00124         { return (_p0 - _p1).SquaredNorm(); }
00126         void Flip()
00127         { PointType t=_p0; _p0=_p1; _p1=t; }
00129         template <class Q>
00130         inline void Import( const Segment3<Q> & b )
00131         { _p0.Import( b.P0() ); _p1.Import( b.P1() );
00132         }
00134         template <class Q>
00135         static SegmentType Construct( const Segment3<Q> & b )
00136         { return SegmentType(PointType::Construct(b.P0()), PointType::Construct(b.P1()));}
00137 
00139 
00140         inline SegmentType operator + ( SegmentType const & p) const
00141         {return SegmentType( _p0+p.P0(), _p1+p.P1() );}
00142         inline SegmentType operator - ( SegmentType const & p) const
00143         {return SegmentType( _p0-p.P0(), _p1-p.P1() );}
00144         inline SegmentType operator * ( const ScalarType s ) const
00145         {return SegmentType( _p0*s, _p1*s );}
00146         inline SegmentType operator / ( const ScalarType s ) const
00147         {ScalarType s0=((ScalarType)1.0)/s; return SegmentType( _p0*s0, _p1*s0 );}
00149 
00150 }; // end class definition
00151 
00152 
00153 
00154 typedef Segment3<short>  Segment3s;
00155 typedef Segment3<int>      Segment3i;
00156 typedef Segment3<float>  Segment3f;
00157 typedef Segment3<double> Segment3d;
00158 
00159 /*
00160 * Computes the minimum distance between a segment and a point
00161 * @param[in] segment    The input segment
00162 * @param[in] p                          The input point
00163 * @return                                                       The distance between the segment and the point p
00164 */
00165 template < class ScalarType >
00166 ScalarType SquaredDistance(Segment3< ScalarType > &segment, Point3< ScalarType > &p)
00167 {
00168         typedef typename vcg::Point3< ScalarType > Point3t;
00169 
00170         Point3t  dir = (segment.P1()-segment.P0()).Normalize();
00171         ScalarType h = dir * (p-segment.P0());
00172         if                      (h<=ScalarType(0.0))    return vcg::SquaredDistance<ScalarType>(p, segment.P0());
00173         else if (h>=segment.Length())   return vcg::SquaredDistance<ScalarType>(p, segment.P1());
00174         else
00175         {
00176                 dir = segment.P0() + dir*h;
00177                 return vcg::SquaredDistance<ScalarType>(p, dir);
00178         }
00179 }; //end of Distance method
00180 
00181 template <class ScalarType> 
00182 Point3<ScalarType> ClosestPoint( Segment3<ScalarType> s, const Point3<ScalarType> & p) 
00183 {
00184         vcg::Line3<ScalarType> l;
00185         l.Set(s.P0(),s.P1()-s.P0());
00186         l.Normalize();
00187         Point3<ScalarType> clos=vcg::ClosestPoint<ScalarType,true>(l,p) ;//attention to call
00188         vcg::Box3<ScalarType> b;
00189         b.Add(s.P0());
00190         b.Add(s.P1());
00191         if (b.IsIn(clos))
00192                 return clos;
00193         else
00194         {
00195                 ScalarType d0=(s.P0()-p).Norm();
00196                 ScalarType d1=(s.P1()-p).Norm();
00197                 if (d0<d1)
00198                         return (s.P0());
00199                 else
00200                         return (s.P1());
00201         }
00202         /*ScalarType t = s.Projection(p); 
00203         if (s<0) return s.P0();
00204         if (s>1) return s.P0();
00205         return s.P(t);*/ 
00206 }
00207 
00210 } // end namespace
00211 #endif