testGenericLatticeConvexHull.cpp

Go to the documentation of this file.

#include <iostream>
#include <vector>
#include <algorithm>
#include "DGtal/base/Common.h"
#include "DGtal/kernel/SpaceND.h"
#include "DGtal/geometry/tools/GenericLatticeConvexHull.h"
#include "DGtal/geometry/tools/AffineGeometry.h"
#include "DGtalCatch.h"
 
using namespace std;
using namespace DGtal;
 
std::random_device rd;
std::mt19937 g(rd());
 
template <typename Point>
std::vector< Point >
randomPointsInBall( int nb, int R )
{
  std::vector< Point > V;
  Point c = Point::diagonal( R );
  double R2 = (double) R * (double) R;
  for ( int i = 0; i < nb; ) {
    Point p;
    for ( DGtal::Dimension k = 0; k < Point::dimension; ++k )
      p[ k ] = rand() % (2*R);
    if ( ( p - c ).squaredNorm() < R2 ) { V.push_back( p ); i++; }
  }
  return V;
}
 
template < typename Point >
std::vector< Point >
makeRandomLatticePointsFromDirVectors( int nb, const vector< Point>& V )
{
  std::uniform_int_distribution<int> U(-10, 10);
  vector< Point > P;
  int n = V[0].size();
  int m = V.size();
  Point A;
  for ( auto i = 0; i < n; i++ )
    A[ i ] = U( g );
  P.push_back( A );
  for ( auto k = 0; k < nb; k++ )
    {
      Point B = A;
      for ( auto i = 0; i < m; i++ )
        {
          int l = U( g );
          B += l * V[ i ];
        }
      P.push_back( B );
    }
  std::shuffle( P.begin(), P.end(), g );
  return P;
}
 
// ///////////////////////////////////////////////////////////////////////////////
// // Functions for testing class GenericLatticeConvexHull in 2D.
// ///////////////////////////////////////////////////////////////////////////////
 
SCENARIO( "GenericLatticeConvexHull< ConvexHullIntegralKernel< 2 > > unit tests", "[genquickhull][integral_kernel][2d]" )
{
  typedef GenericLatticeConvexHull< 2, int > CvxHull;
  typedef SpaceND< 2, int >                Space;
  typedef Space::Point                     Point;
 
 
  GIVEN( "Given a set { } " ) {
    std::vector<Point> V = { };
    CvxHull hull;
    bool ok = hull.compute( V );
    std::cout << hull << std::endl;
    THEN( "Everything went fine and dim=-1." ) {
      REQUIRE( ok );
      REQUIRE( hull.affine_dimension == -1 );
      REQUIRE( hull.count() == 0 );
    }
  }
  GIVEN( "Given a set { (2,1), (2,1) } " ) {
    std::vector<Point> V
      = { Point(2,1), Point(2,1) };
    CvxHull hull;
    bool ok = hull.compute( V );
    std::cout << hull << std::endl;
    THEN( "Everything went fine and dim=0." ) {
      REQUIRE( ok );
      REQUIRE( hull.affine_dimension == 0 );
      REQUIRE( hull.count() == 1 );
    }
  }
  GIVEN( "Given a set { (0,0), (-4,-1), (8, 2), (16,4) } " ) {
    std::vector<Point> V
      = { Point(0,0), Point(-4,-1), Point(8,2), Point(16,4) };
    CvxHull hull;
    bool ok = hull.compute( V );
    std::cout << hull << std::endl;
    THEN( "Everything went fine and dim=1." ) {
      REQUIRE( ok );
      REQUIRE( hull.affine_dimension == 1 );
      REQUIRE( hull.count() == 6 );
    }
  }
  GIVEN( "Given a set { (0,0), (-4,-1), (-3,5), (7,3), (5, -2), (2, 2) } " ) {
    std::vector<Point> V
      = { Point(0,0), Point(-4,-1), Point(-3,5), Point(7,3), Point(5, -2), Point(2,2) };
    CvxHull hull;
    bool ok = hull.compute( V );
    std::cout << hull << std::endl;
    THEN( "Everything went fine and dim=2." ) {
      REQUIRE( ok );
      REQUIRE( hull.affine_dimension == 2 );
      REQUIRE( hull.count() > V.size() );
    }
  }
 
}
 
SCENARIO( "GenericLatticeConvexHull< ConvexHullIntegralKernel< 3 > > unit tests", "[genquickhull][integral_kernel][3d]" )
{
  typedef GenericLatticeConvexHull< 3, int > CvxHull;
  typedef SpaceND< 3, int >                Space;
  typedef Space::Point                     Point;
 
  std::vector< Point > V1 = { Point{ 5,-2, 1 } };
  std::vector< Point > X1 = makeRandomLatticePointsFromDirVectors( 20, V1 );
  std::vector< Point > V2 = { Point{ 5,-2, 1 }, Point{ -3, 4, 2 } };
  std::vector< Point > X2 = makeRandomLatticePointsFromDirVectors( 20, V2 );
  std::vector< Point > V3 = { Point{ 5,-2, 1 }, Point{ -3, 4, 2 }, Point{ 1, -7, 11 } };
  std::vector< Point > X3 = makeRandomLatticePointsFromDirVectors( 20, V3 );
 
  GIVEN( "Given a 1-d lattice set in Z3 " ) {
    CvxHull hull;
    bool ok = hull.compute( X1 );
    std::cout << hull << std::endl;
    THEN( "Everything went fine and dim=1." ) {
      CAPTURE( hull.positions );
      REQUIRE( ok );
      REQUIRE( hull.affine_dimension == 1 );
      REQUIRE( hull.count() >= 2 );
    }
  }
  GIVEN( "Given a 2-d lattice set in Z3 " ) {
    CvxHull hull;
    bool ok = hull.compute( X2 );
    std::cout << hull << std::endl;
    THEN( "Everything went fine and dim=2." ) {
      REQUIRE( ok );
      REQUIRE( hull.affine_dimension == 2 );
      REQUIRE( hull.count() >= 3 );
    }
  }
  GIVEN( "Given a 3-d lattice set in Z3 " ) {
    CvxHull hull;
    bool ok = hull.compute( X3 );
    std::cout << hull << std::endl;
    THEN( "Everything went fine and dim=3." ) {
      REQUIRE( ok );
      REQUIRE( hull.affine_dimension == 3 );
      REQUIRE( hull.count() >= 4 );
    }
  }
}