mirror of https://github.com/CGAL/cgal
125 lines
3.7 KiB
C++
125 lines
3.7 KiB
C++
// Copyright (c) 1998 Utrecht University (The Netherlands),
|
|
// ETH Zurich (Switzerland), Freie Universitaet Berlin (Germany),
|
|
// INRIA Sophia-Antipolis (France), Martin-Luther-University Halle-Wittenberg
|
|
// (Germany), Max-Planck-Institute Saarbruecken (Germany), RISC Linz (Austria),
|
|
// and Tel-Aviv University (Israel). All rights reserved.
|
|
//
|
|
// This file is part of CGAL (www.cgal.org); 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; version 2.1 of the License.
|
|
// See the file LICENSE.LGPL distributed with CGAL.
|
|
//
|
|
// Licensees holding a valid commercial license may use this file in
|
|
// accordance with the commercial license agreement provided with the software.
|
|
//
|
|
// This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
|
|
// WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
|
|
//
|
|
// $URL$
|
|
// $Id$
|
|
//
|
|
//
|
|
// Author(s) : Michael Hoffmann <hoffmann@inf.ethz.ch>
|
|
|
|
#if ! (CGAL_RANDOM_CONVEX_SET_2_H)
|
|
#define CGAL_RANDOM_CONVEX_SET_2_H 1
|
|
|
|
#include <CGAL/basic.h>
|
|
#include <CGAL/algorithm.h>
|
|
#include <vector>
|
|
#include <algorithm>
|
|
#include <numeric>
|
|
#include <CGAL/Random_convex_set_traits_2.h>
|
|
#include <CGAL/centroid.h>
|
|
|
|
CGAL_BEGIN_NAMESPACE
|
|
|
|
template < class OutputIterator, class Point_generator, class Traits >
|
|
OutputIterator
|
|
random_convex_set_2( int n,
|
|
OutputIterator o,
|
|
const Point_generator& pg,
|
|
Traits t)
|
|
{
|
|
CGAL_precondition( n >= 3);
|
|
|
|
using std::vector;
|
|
using std::back_inserter;
|
|
using std::accumulate;
|
|
using std::transform;
|
|
using std::bind2nd;
|
|
using std::sort;
|
|
using std::partial_sum;
|
|
using std::less;
|
|
using std::max_element;
|
|
using CGAL::copy_n;
|
|
|
|
typedef typename Traits::Point_2 Point_2;
|
|
typedef typename Traits::FT FT;
|
|
typedef vector< Point_2 > Container;
|
|
typedef typename Traits::Sum Sum;
|
|
typedef typename Traits::Scale Scale;
|
|
typedef typename Traits::Angle_less Angle_less;
|
|
typedef typename Traits::Max_coordinate Max_coordinate;
|
|
|
|
// GCC 2.8 and egcs-1.0.1 require these:
|
|
// (does not accept s.l. Scale()( p, 1))
|
|
Scale scale;
|
|
Max_coordinate max_coordinate;
|
|
Sum sum;
|
|
|
|
// build random point set:
|
|
Container points;
|
|
points.reserve( n);
|
|
CGAL::copy_n( pg, n, back_inserter( points));
|
|
|
|
// compute centroid of points:
|
|
Point_2 centroid = CGAL::centroid( points.begin(), points.end(), t );
|
|
|
|
// translate s.t. centroid == origin:
|
|
transform(
|
|
points.begin(),
|
|
points.end(),
|
|
points.begin(),
|
|
bind2nd( Sum(), scale( centroid, FT( -1))));
|
|
|
|
// sort them according to their direction's angle
|
|
// w.r.t. the positive x-axis:
|
|
sort( points.begin(), points.end(), Angle_less());
|
|
|
|
// construct polygon:
|
|
partial_sum(
|
|
points.begin(), points.end(), points.begin(), Sum());
|
|
|
|
// and compute its centroid:
|
|
Point_2 new_centroid = CGAL::centroid( points.begin(), points.end(), t );
|
|
|
|
// translate s.t. centroids match:
|
|
transform(
|
|
points.begin(),
|
|
points.end(),
|
|
points.begin(),
|
|
bind2nd( Sum(), sum( centroid,
|
|
scale( new_centroid, FT( -1)))));
|
|
|
|
// compute maximal coordinate:
|
|
FT maxcoord( max_coordinate(
|
|
*max_element( points.begin(),
|
|
points.end(),
|
|
compose2_2( less< FT >(),
|
|
Max_coordinate(),
|
|
Max_coordinate()))));
|
|
|
|
// and finally scale to fit into original grid:
|
|
return transform(
|
|
points.begin(),
|
|
points.end(),
|
|
o,
|
|
bind2nd( Scale(), FT( pg.range()) / maxcoord));
|
|
|
|
} // random_convex_set_2( n, o, pg, t)
|
|
|
|
CGAL_END_NAMESPACE
|
|
|
|
#endif // ! (CGAL_RANDOM_CONVEX_SET_2_H)
|