testConvexHull2D.cpp File Reference

#include <iostream>
#include "DGtal/base/Common.h"
#include "DGtal/base/Circulator.h"
#include "DGtal/kernel/PointVector.h"
#include "DGtal/geometry/tools/Hull2DHelpers.h"
#include "DGtal/geometry/tools/PolarPointComparatorBy2x2DetComputer.h"
#include "DGtal/geometry/tools/determinant/InHalfPlaneBySimple3x3Matrix.h"
#include "DGtal/geometry/tools/determinant/PredicateFromOrientationFunctor2.h"
#include "DGtal/io/boards/Board2D.h"

Go to the source code of this file.

Functions
template<typename ForwardIterator >
bool	circularlyEqual (const ForwardIterator &first1, const ForwardIterator &last1, const ForwardIterator &first2, const ForwardIterator &last2)
bool	testConvexHull2D ()
bool	testConvexHullCompThickness ()
int	main (int argc, char **argv)

Detailed Description

This program 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 3 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, see http://www.gnu.org/licenses/.

Author

Tristan Roussillon (trist.nosp@m.an.r.nosp@m.oussi.nosp@m.llon.nosp@m.@liri.nosp@m.s.cn.nosp@m.rs.fr ) Laboratoire d'InfoRmatique en Image et Systèmes d'information - LIRIS (CNRS, UMR 5205), CNRS, France

Date

2013/12/06

Functions for testing the functions devoted to convex hull computations.

This file is part of the DGtal library.

Definition in file testConvexHull2D.cpp.

Function Documentation

circularlyEqual()

template<typename ForwardIterator >

bool circularlyEqual	(	const ForwardIterator &	first1,
		const ForwardIterator &	last1,
		const ForwardIterator &	first2,
		const ForwardIterator &	last2
	)

Function that checks whether two ranges are equal up to circular shifts or not. For example, (1, 2, 3) and (2, 3, 1) are equal, but (1, 2, 3) and (2, 1, 3) are not equal.

Parameters

first1	begin iterator of the first range
last1	end iterator of the first range
first2	begin iterator of the second range
last2	end iterator of the second range

Template Parameters

ForwardIterator

a model of forward iterator

Returns

'true' if the two ranges are equal, 'false' otherwise

Definition at line 66 of file testConvexHull2D.cpp.

{
  ASSERT( first2 != last2 ); 
 
  //find a element of the first range equal to the first element of the second range
  ForwardIterator start1 = find( first1, last1, *first2 );
  if (start1 == last1)
    return false; 
  else
    {
      bool areEqual = true; //true if the two ranges are equal up to circular shifts
      //check whether the two ranges are equal or not
      Circulator<ForwardIterator> c1(start1, first1, last1); 
      Circulator<ForwardIterator> cEnd1 = c1; 
      Circulator<ForwardIterator> c2(first2, first2, last2); 
      do
        {
          if (*c1 != *c2)
            areEqual = false; 
          else
            {
              ++c1; 
              ++c2; 
            }
        } while ( (c1 != cEnd1) && (areEqual) ); 
      return areEqual; 
 
    }
}

Referenced by testConvexHull2D().

main()

int main	(	int	argc,
		char **	argv
	)

Definition at line 370 of file testConvexHull2D.cpp.

{
  trace.beginBlock ( "Testing convex hull function" );
  trace.info() << "Args:";
  for ( int i = 0; i < argc; ++i )
    trace.info() << " " << argv[ i ];
  trace.info() << endl;
 
  bool res = testConvexHull2D() &&testConvexHullCompThickness();
  trace.emphase() << ( res ? "Passed." : "Error." ) << endl;
  trace.endBlock();
  return res ? 0 : 1;
}

References DGtal::Trace::beginBlock(), DGtal::Trace::emphase(), DGtal::Trace::endBlock(), DGtal::Trace::info(), testConvexHull2D(), testConvexHullCompThickness(), and DGtal::trace.

testConvexHull2D()

bool testConvexHull2D

(

)

Testing functions that computes the convex hull of a range of points

Returns

'true' if passed.

Definition at line 102 of file testConvexHull2D.cpp.

{
  unsigned int nbok = 0;
  unsigned int nb = 0;
 
  typedef PointVector<2,DGtal::int32_t> Point;
  
  trace.beginBlock ( "One simple test..." );
 
  vector<Point> data, g, res; 
  //data
  data.push_back( Point(2,0) );
  data.push_back( Point(4,0) ); 
  data.push_back( Point(0,3) );
  data.push_back( Point(0,-4) ); 
  data.push_back( Point(3,4) );
  data.push_back( Point(5,0) ); 
  data.push_back( Point(4,3) );
  data.push_back( Point(0,5) ); 
  data.push_back( Point(-3,-4) );
  data.push_back( Point(-5,0) ); 
  data.push_back( Point(-4,-3) );
  data.push_back( Point(0,-5) );
  data.push_back( Point(3,-4) );
  data.push_back( Point(4,-3) );
  data.push_back( Point(-3,4) );
  data.push_back( Point(-4,3) );
  //ground truth
  g.push_back( Point(5,0) ); 
  g.push_back( Point(4,3) );
  g.push_back( Point(3,4) );
  g.push_back( Point(0,5) ); 
  g.push_back( Point(-3,4) );
  g.push_back( Point(-4,3) );
  g.push_back( Point(-5,0) ); 
  g.push_back( Point(-4,-3) );
  g.push_back( Point(-3,-4) );
  g.push_back( Point(0,-5) );
  g.push_back( Point(3,-4) );
  g.push_back( Point(4,-3) );
 
  //geometric predicate
  typedef InHalfPlaneBySimple3x3Matrix<Point, DGtal::int64_t> Functor;  
  Functor functor; 
  typedef PredicateFromOrientationFunctor2<Functor> Predicate; 
  Predicate predicate( functor ); 
 
  //namespace
  using namespace functions::Hull2D; 
 
  //andrew algorithm
  trace.info() << " andrew algorithm " << std::endl; 
  andrewConvexHullAlgorithm( data.begin(), data.end(), back_inserter( res ), predicate );   
 
  copy(res.begin(), res.end(), ostream_iterator<Point>( cout, " " ) ); 
  cout << endl; 
 
  if ( (res.size() == g.size()) && 
        (circularlyEqual(res.begin(), res.end(), g.begin(), g.end())) )
    nbok++; 
  nb++; 
  trace.info() << "(" << nbok << "/" << nb << ") " << endl;
 
  //graham algorithm
  res.clear(); 
  trace.info() << " graham algorithm " << std::endl;
  functors::PolarPointComparatorBy2x2DetComputer<Point> comparator;  
  grahamConvexHullAlgorithm( data.begin(), data.end(), back_inserter( res ), predicate, comparator );
 
  copy(res.begin(), res.end(), ostream_iterator<Point>( cout, " " ) ); 
  cout << endl; 
 
  if ( (res.size() == g.size()) && 
        (circularlyEqual(res.begin(), res.end(), g.begin(), g.end())) )
    nbok++; 
  nb++; 
  trace.info() << "(" << nbok << "/" << nb << ") " << endl;
 
  //melkman algorithm
  res.clear(); 
  trace.info() << " melkman algorithm " << std::endl;
  sort( data.begin(), data.end() ); 
  melkmanConvexHullAlgorithm( data.begin(), data.end(), back_inserter( res ), functor );
 
  copy(res.begin(), res.end(), ostream_iterator<Point>( cout, " " ) ); 
  cout << endl; 
 
  if ( (res.size() == g.size()) && 
        (circularlyEqual(res.begin(), res.end(), g.begin(), g.end())) )
    nbok++; 
  nb++; 
  trace.info() << "(" << nbok << "/" << nb << ") " << endl;
  // melkman on line construction of  convex hull:
  trace.info() << "on line convex hull construction" << std::endl;
  DGtal::MelkmanConvexHull<Point, Functor> ch; 
  for(vector<Point>::const_iterator it = data.begin(); it != data.end(); it++)
    {
      ch.add(*it);
    }
 
 
  unsigned int cvSize = 0;
  for(DGtal::MelkmanConvexHull<Point, Functor>::ConstIterator it = ch.begin(); it != ch.end(); it++, cvSize++)
    {
      trace.info() << *it ;
    };
  trace.info() << std::endl;
 
  if(res.size() == cvSize && (cvSize == ch.size()))
    nbok++;
  nb++;
 
  trace.info() << "(" << nbok << "/" << nb << ") " << endl;  
  // test copy and [] operator on convex hull:
  trace.info() << "test copy and [] operator on convex hull:" << std::endl;
  DGtal::MelkmanConvexHull<Point, Functor> ch2 = ch;
  unsigned int cvSize2 = 0;
  for(DGtal::MelkmanConvexHull<Point, Functor>::ConstIterator it = ch.begin(); it != ch.end(); it++, cvSize2++)
    {
      trace.info() << *it ;
    };
   if(res.size() == cvSize2 && ch[0] == ch2[0])
    nbok++;
  nb++;
  trace.info() << "(" << nbok << "/" << nb << ") " << endl;  
  trace.endBlock();
 
 
  trace.beginBlock ( "Random Tests..." );
  vector<Point> randomData, res1, res2; 
  const int numberOfPoints = 1000; 
  const int numberOfTries = 50; 
  
  for (int i = 0; ( (i < numberOfTries)&&(nbok == nb) ); i++)
    {
      //new data
      randomData.clear(); 
      res1.clear(); 
      res2.clear(); 
      for (int j = 0; j < numberOfPoints; j++)
          randomData.push_back( Point(rand()%256, rand()%256) ); 
      //computation
      andrewConvexHullAlgorithm( randomData.begin(), randomData.end(), back_inserter( res1 ), predicate );   
      grahamConvexHullAlgorithm( randomData.begin(), randomData.end(), back_inserter( res2 ), predicate, comparator );
      //comparison
      if ( (res1.size() == res2.size()) && 
           (circularlyEqual(res1.begin(), res1.end(), res2.begin(), res2.end())) )
        nbok++; 
      nb++; 
      trace.info() << "(" << nbok << "/" << nb << ") " << endl;
      //another computation
      res2.clear(); 
      sort( randomData.begin(), randomData.end() ); 
      melkmanConvexHullAlgorithm( randomData.begin(), randomData.end(), back_inserter( res2 ), functor );   
      //comparison
      if ( (res1.size() == res2.size()) && 
           (circularlyEqual(res1.begin(), res1.end(), res2.begin(), res2.end())) )
        nbok++; 
      nb++; 
      trace.info() << "(" << nbok << "/" << nb << ") " << endl;
    }
 
  trace.endBlock();
  
  return nbok == nb;
}

References DGtal::Trace::beginBlock(), ch, circularlyEqual(), DGtal::Trace::endBlock(), DGtal::Trace::info(), and DGtal::trace.

Referenced by main().

testConvexHullCompThickness()

bool testConvexHullCompThickness

(

)

Testing functions that computes the convex hull thickness.

Returns

'true' if passed.

Definition at line 274 of file testConvexHull2D.cpp.

{
  unsigned int nbok = 0;
  unsigned int nb = 0;
  typedef PointVector<2,DGtal::int32_t> Point;
  typedef InHalfPlaneBySimple3x3Matrix<Point, DGtal::int32_t> Functor;  
  
  trace.beginBlock ( "One simple test..." );
  DGtal::MelkmanConvexHull<Point, Functor> ch; 
  ch.add(Point(0,0));
  ch.add(Point(11,1));
  ch.add(Point(12,3));
  ch.add(Point(8,3));
  ch.add(Point(4,5));
  ch.add(Point(2,6));
  ch.add(Point(1,4));
 
  Point antipodalP, antipodalQ, antipodalS;
  double thicknessE = DGtal::functions::Hull2D::computeHullThickness(ch.begin(), ch.end(), 
                                                                     DGtal::functions::Hull2D::EuclideanThickness, 
                                                                     antipodalP,
                                                                     antipodalQ,
                                                                     antipodalS);
  double thicknessHV = DGtal::functions::Hull2D::computeHullThickness(ch.begin(), ch.end(), 
                                                                      DGtal::functions::Hull2D::HorizontalVerticalThickness,
                                                                      antipodalP, antipodalQ, antipodalS);
  double thicknessHVb = DGtal::functions::Hull2D::computeHullThickness(ch.begin(), ch.end(), 
                                            DGtal::functions::Hull2D::HorizontalVerticalThickness);
  
  
  Board2D aBoard;
  for(DGtal::MelkmanConvexHull<Point, Functor>::ConstIterator it = ch.begin(); it != ch.end(); it++){
    if(it != ch.end()-1)
      aBoard.drawLine((*it)[0], (*it)[1], (*(it+1))[0], (*(it+1))[1]);
    else{
      aBoard.drawLine((*it)[0], (*it)[1], (*(ch.begin()))[0], (*(ch.begin()))[1]);
    }
    aBoard << *it;
  }
  
  aBoard.setPenColor(DGtal::Color::Red);
  aBoard.drawCircle( antipodalS[0], antipodalS[1], 1.0) ;
  aBoard.setPenColor(DGtal::Color::Blue);
  aBoard.drawCircle(antipodalP[0], antipodalP[1], 1.0);
  aBoard.drawCircle(antipodalQ[0], antipodalQ[1], 1.0);
  
  aBoard.drawLine(antipodalP[0], antipodalP[1], antipodalQ[0], antipodalQ[1]);
  double awaitedThHV = DGtal::functions::Hull2D::getThicknessAntipodalPair(Point(0,0), Point(11,1), Point(2,6), DGtal::functions::Hull2D::HorizontalVerticalThickness );
  double awaitedThE = DGtal::functions::Hull2D::getThicknessAntipodalPair(Point(0,0), Point(11,1), Point(2,6), DGtal::functions::Hull2D::EuclideanThickness );
  trace.info() << "Thickness HV = " << thicknessHV << std::endl;
  trace.info() << "Expected Thickness HV  = " << awaitedThHV << std::endl;
  trace.info() << "Thickness Euclidean = " << thicknessE << std::endl;
  trace.info() << "Expected Euclidean Thickness  = " << awaitedThE << std::endl;
  aBoard.saveEPS("testConvexHull2D_Thickness.eps");
 
  // testing tickness after changing begin points.
   std::vector<Z2i::RealPoint> hull {
    {804.56832227024199, -68.471176393526704},
    {804.96020257363512, -69.494933490400683},
    {805.35232247974727, -70.519316530915930},
    {825.15497274857830, -114.34711249674335},
    {828.67425867587508, -121.69593677670120},
    {829.05943325037651, -122.39546351563243},
    {829.42436256177677, -122.73833140123513},
    {827.82353937509288, -118.87280445059109},
    {811.06291230576301, -82.124832029926566},
    {806.83483124583609, -72.890457996792406},
    {804.92531970702396, -68.803808853026638},
    {804.55092650722997, -68.125792709291431},
  };
 
   double th = DGtal::functions::Hull2D::computeHullThickness(hull.begin(), hull.end(),
                                                              DGtal::functions::Hull2D::HorizontalVerticalThickness);
   std::rotate(hull.begin(), hull.begin() + 1, hull.end());
   double th2 = DGtal::functions::Hull2D::computeHullThickness(hull.begin(), hull.end(),
                                                               DGtal::functions::Hull2D::HorizontalVerticalThickness);
   std::rotate(hull.begin(), hull.begin() + 5, hull.end());
   double th3 = DGtal::functions::Hull2D::computeHullThickness(hull.begin(), hull.end(),
                                                               DGtal::functions::Hull2D::HorizontalVerticalThickness);
   trace.info() << "Thickness (before change init point)  = " << th << std::endl;
   trace.info() << "Thickness (after change init point) = " << th2 << std::endl;
   trace.info() << "Thickness (after change init point) = " << th3 << std::endl;
    
   nbok += thicknessHV == awaitedThHV && thicknessE == awaitedThE &&
           thicknessHVb == thicknessHV && abs(th - th2) < 0.000001 &&
           th - 0.604414 < 0.000001 && abs(th - th3) < 0.000001 ;
   nb++;
   return nb==nbok;
}

References DGtal::Trace::beginBlock(), DGtal::Color::Blue, ch, DGtal::functions::Hull2D::computeHullThickness(), LibBoard::Board::drawCircle(), LibBoard::Board::drawLine(), DGtal::functions::Hull2D::EuclideanThickness, DGtal::functions::Hull2D::getThicknessAntipodalPair(), DGtal::functions::Hull2D::HorizontalVerticalThickness, DGtal::Trace::info(), DGtal::Color::Red, LibBoard::Board::saveEPS(), LibBoard::Board::setPenColor(), thicknessE, thicknessHV, and DGtal::trace.

Referenced by main().