803 lines
24 KiB
C
803 lines
24 KiB
C
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// Copyright (c) 1999-2003 ETH Zurich (Switzerland).
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// All rights reserved.
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//
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// This file is part of CGAL (www.cgal.org).
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// You can redistribute it and/or modify it under the terms of the GNU
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// General Public License as published by the Free Software Foundation,
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// either version 3 of the License, or (at your option) any later version.
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//
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// Licensees holding a valid commercial license may use this file in
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// accordance with the commercial license agreement provided with the software.
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//
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// This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
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// WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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//
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// $URL$
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// $Id$
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// SPDX-License-Identifier: GPL-3.0+
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//
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//
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// Author(s) : Michael Hoffmann <hoffmann@inf.ethz.ch> and
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// Emo Welzl <emo@inf.ethz.ch>
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#ifndef CGAL_MIN_QUADRILATERAL_2_H
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#define CGAL_MIN_QUADRILATERAL_2_H 1
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#include <CGAL/license/Bounding_volumes.h>
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#include <CGAL/basic.h>
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#include <CGAL/Optimisation/assertions.h>
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#include <iterator>
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#include <boost/bind.hpp>
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#include <boost/function.hpp>
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#ifdef CGAL_OPTIMISATION_EXPENSIVE_PRECONDITION_TAG
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#include <CGAL/Polygon_2_algorithms.h>
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#endif
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namespace CGAL {
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template < class ForwardIterator, class OutputIterator, class Traits >
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OutputIterator
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convex_bounding_box_2(
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ForwardIterator f, ForwardIterator l, OutputIterator o, Traits& t)
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// PRE:
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// * f != l
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// * value type of ForwardIterator is Traits::Point_2
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// * [f,l) form a the vertices of a convex polygon
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// oriented counterclockwise
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// * OutputIterator accepts ForwardIterator as value type
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// POST:
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// writes to o iterators from [f,l) referring to the last points with
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// - smallest y coordinate
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// - largest x coordinate
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// - largest y coordinate
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// - smallest x coordinate
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// in that order.
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{
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CGAL_precondition(f != l);
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// make sure that we have two distinct points, such that it
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// can be determined in which quadrant of the polygon we are
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ForwardIterator first;
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do {
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first = f;
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// catch the one-element case:
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if (++f == l) {
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f = first;
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break;
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}
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} while (t.equal_2_object()(*first, *f));
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// Four extremes
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ForwardIterator minx = first;
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ForwardIterator maxx;
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ForwardIterator miny;
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ForwardIterator maxy;
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typedef typename Traits::Point_2 Point_2;
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typedef typename Traits::Less_xy_2 Less_xy_2;
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typedef typename Traits::Less_yx_2 Less_yx_2;
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typedef boost::function2<bool,Point_2,Point_2> Greater_xy_2;
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typedef boost::function2<bool,Point_2,Point_2> Greater_yx_2;
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Less_xy_2 less_xy_2 = t.less_xy_2_object();
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Less_yx_2 less_yx_2 = t.less_yx_2_object();
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Greater_xy_2 greater_xy_2 = boost::bind(less_xy_2, _2, _1);
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Greater_yx_2 greater_yx_2 = boost::bind(less_yx_2, _2, _1);
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if (less_xy_2(*minx, *f) ||
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(less_yx_2(*minx, *f) && !less_xy_2(*f, *minx)))
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if (less_yx_2(*minx, *f))
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// first quadrant
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for (;;) {
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maxx = f;
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if (++f == l) {
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maxy = minx = miny = maxx;
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break;
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}
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if (less_xy_2(*f, *maxx)) {
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f = maxx;
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for (;;) {
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maxy = f;
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if (++f == l) {
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minx = miny = maxy;
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break;
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}
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if (less_yx_2(*f, *maxy)) {
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f = maxy;
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for (;;) {
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minx = f;
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if (++f == l) {
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miny = minx;
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break;
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}
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if (greater_xy_2(*f, *minx)) {
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f = minx;
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do
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miny = f;
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while (++f != l && !greater_yx_2(*f, *miny));
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break;
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}
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} // for (;;)
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break;
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} // if (less_yx_2(*f, *maxy))
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} // for (;;)
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break;
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} // if (less_xy_2(*f, *maxx))
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} // for (;;)
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else
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// fourth quadrant
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for (;;) {
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miny = f;
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if (++f == l) {
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maxx = maxy = minx = miny;
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break;
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}
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if (greater_yx_2(*f, *miny)) {
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f = miny;
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for (;;) {
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maxx = f;
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if (++f == l) {
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maxy = minx = maxx;
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break;
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}
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if (less_xy_2(*f, *maxx)) {
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f = maxx;
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for (;;) {
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maxy = f;
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if (++f == l) {
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minx = maxy;
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break;
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}
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if (less_yx_2(*f, *maxy)) {
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f = maxy;
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do
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minx = f;
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while (++f != l && !greater_xy_2(*f, *minx));
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break;
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}
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} // for (;;)
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break;
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} // if (less_xy_2(*f, *maxx))
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} // for (;;)
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break;
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} // if (greater_yx_2(*f, *miny))
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} // for (;;)
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else
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if (less_yx_2(*f, *minx))
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// third quadrant
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for (;;) {
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minx = f;
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if (++f == l) {
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miny = maxx = maxy = minx;
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break;
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}
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if (greater_xy_2(*f, *minx)) {
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f = minx;
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for (;;) {
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miny = f;
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if (++f == l) {
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maxx = maxy = miny;
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break;
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}
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if (greater_yx_2(*f, *miny)) {
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f = miny;
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for (;;) {
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maxx = f;
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if (++f == l) {
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maxy = maxx;
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break;
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}
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if (less_xy_2(*f, *maxx)) {
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f = maxx;
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do
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maxy = f;
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while (++f != l && !less_yx_2(*f, *maxy));
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break;
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}
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} // for (;;)
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break;
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} // if (greater_yx_2(*f, *miny))
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} // for (;;)
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break;
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} // if (greater_xy_2(*f, *minx))
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} // for (;;)
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else
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// second quadrant
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for (;;) {
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maxy = f;
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if (++f == l) {
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minx = miny = maxx = maxy;
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break;
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}
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if (less_yx_2(*f, *maxy)) {
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f = maxy;
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for (;;) {
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minx = f;
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if (++f == l) {
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miny = maxx = minx;
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break;
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}
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if (greater_xy_2(*f, *minx)) {
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f = minx;
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for (;;) {
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miny = f;
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if (++f == l) {
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maxx = miny;
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break;
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}
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if (greater_yx_2(*f, *miny)) {
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f = miny;
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do
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maxx = f;
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while (++f != l && !less_xy_2(*f, *maxx));
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break;
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}
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} // for (;;)
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break;
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} // if (greater_xy_2(*f, *minx))
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} // for (;;)
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break;
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} // if (less_yx_2(*f, *maxy))
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} // for (;;)
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// Output
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*o++ = less_yx_2(*first, *miny) ? first : miny;
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*o++ = less_xy_2(*maxx, *first) ? first : maxx;
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*o++ = less_yx_2(*maxy, *first) ? first : maxy;
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*o++ = less_xy_2(*first, *minx) ? first : minx;
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return o;
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} // convex_bounding_box_2(f, l, o, t)
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namespace Optimisation {
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// Adds certain redundant functionality for convenience
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template < typename Traits >
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struct Min_quadrilateral_traits_wrapper : public Traits
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{
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typedef Traits Base;
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// types inherited from Traits
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typedef typename Base::Point_2 Point_2;
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typedef typename Base::Direction_2 Direction_2;
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// predicates and constructions inherited from Traits
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typedef typename Base::Has_on_negative_side_2 HONS;
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typedef typename Base::Construct_vector_2 CV2;
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typedef typename Base::Construct_direction_2 CD2;
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typedef typename Base::Construct_line_2 Construct_line_2;
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typedef typename Base::Compare_angle_with_x_axis_2 CAWXA;
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using Traits::has_on_negative_side_2_object;
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using Traits::construct_line_2_object;
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using Traits::construct_vector_2_object;
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using Traits::compare_angle_with_x_axis_2_object;
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Min_quadrilateral_traits_wrapper(const Traits& bt) : Base(bt) {}
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// ---------------------------------------------------------------
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// Right_of_implicit_line_2
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// ---------------------------------------------------------------
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typedef boost::function3<bool,Point_2,Point_2,Direction_2>
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Right_of_implicit_line_2;
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Right_of_implicit_line_2 right_of_implicit_line_2_object() const {
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return boost::bind(has_on_negative_side_2_object(),
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boost::bind(construct_line_2_object(), _2, _3),
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_1);
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}
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typedef boost::function2<Direction_2,Point_2,Point_2>
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Construct_direction_2;
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Construct_direction_2 construct_direction_2_object() const {
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return boost::bind(Base::construct_direction_2_object(),
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boost::bind(construct_vector_2_object(), _1, _2));
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}
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template < class Kernel >
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class Rdbmop
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: public CGAL::cpp98::binary_function< Direction_2, int, Direction_2 >
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{
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typename Kernel::Construct_perpendicular_vector_2 cperpvec;
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typename Kernel::Construct_vector_from_direction_2 cvec;
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typename Kernel::Construct_direction_2 dir;
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typename Kernel::Construct_opposite_direction_2 oppdir;
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public:
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Rdbmop() {}
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Rdbmop(const Kernel& k)
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: cperpvec(k.construct_perpendicular_vector_2_object()),
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cvec(k.construct_vector_from_direction_2_object()),
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dir(k.construct_direction_2_object()),
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oppdir(k.construct_opposite_direction_2_object())
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{}
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Direction_2
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operator()(const Direction_2& d, int i) const
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{
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// FIXME: here I would like to construct a vector from a
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// direction, but this is not in the kernel concept
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// maybe, we can get rid of directions soon...
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CGAL_precondition(i >= 0 && i < 4);
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if (i == 0) return d;
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if (i == 1) return dir(cperpvec(cvec(d), CLOCKWISE));
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if (i == 2) return oppdir(d);
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return dir(cperpvec(cvec(d), COUNTERCLOCKWISE));
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}
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};
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typedef Rdbmop<Traits> Rotate_direction_by_multiple_of_pi_2;
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Rotate_direction_by_multiple_of_pi_2
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rotate_direction_by_multiple_of_pi_2_object() const
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{ return Rotate_direction_by_multiple_of_pi_2(*this); }
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typedef boost::function2<bool,Direction_2,Direction_2>
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Less_angle_with_x_axis_2;
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Less_angle_with_x_axis_2 less_angle_with_x_axis_2_object() const {
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return boost::bind(std::equal_to<Comparison_result>(),
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boost::bind(compare_angle_with_x_axis_2_object(),
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_1, _2),
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SMALLER);
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}
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};
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} // namespace Optimisation
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template < class ForwardIterator, class OutputIterator, class BTraits >
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OutputIterator
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min_rectangle_2(
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ForwardIterator f,
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ForwardIterator l,
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OutputIterator o,
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BTraits& bt)
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{
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typedef Optimisation::Min_quadrilateral_traits_wrapper<BTraits> Traits;
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Traits t(bt);
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CGAL_optimisation_expensive_precondition(is_convex_2(f, l, t));
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CGAL_optimisation_expensive_precondition(
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orientation_2(f, l, t) == COUNTERCLOCKWISE);
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// check for trivial cases
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if (f == l) return o;
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ForwardIterator tst = f;
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if (++tst == l) {
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// all points are equal
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for (int i = 0; i < 4; ++i) *o++ = *f;
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return o;
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}
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// types from the traits class
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typedef typename Traits::Rectangle_2 Rectangle_2;
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typedef typename Traits::Direction_2 Direction_2;
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typedef typename Traits::Construct_direction_2 Construct_direction_2;
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typedef typename Traits::Construct_rectangle_2 Construct_rectangle_2;
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Construct_direction_2 direction = t.construct_direction_2_object();
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Construct_rectangle_2 rectangle = t.construct_rectangle_2_object();
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typename Traits::Rotate_direction_by_multiple_of_pi_2
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rotate = t.rotate_direction_by_multiple_of_pi_2_object();
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typename Traits::Less_angle_with_x_axis_2
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less_angle = t.less_angle_with_x_axis_2_object();
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typename Traits::Area_less_rectangle_2
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area_less = t.area_less_rectangle_2_object();
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// quadruple of points defining the current rectangle
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ForwardIterator curr[4];
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// initialised to the points defining the bounding box
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convex_bounding_box_2(f, l, curr, t);
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// curr[i] can be advanced (cyclically) until it reaches limit[i]
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ForwardIterator limit[4];
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limit[0] = curr[1], limit[1] = curr[2],
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limit[2] = curr[3], limit[3] = curr[0];
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// quadruple of direction candidates defining the current rectangle
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Direction_2 dir[4];
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for (int i = 0; i < 4; i++) {
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ForwardIterator cp = curr[i];
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if (++cp == l)
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cp = f;
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dir[i] = rotate(direction(*(curr[i]), *cp), i);
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}
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int yet_to_finish = 0;
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for (int i1 = 0; i1 < 4; ++i1) {
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CGAL_optimisation_assertion(limit[i1] != l);
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if (curr[i1] != limit[i1])
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++yet_to_finish;
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}
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int low = less_angle(dir[0], dir[1]) ? 0 : 1;
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int upp = less_angle(dir[2], dir[3]) ? 2 : 3;
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int event = less_angle(dir[low], dir[upp]) ? low : upp;
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Rectangle_2 rect_so_far =
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rectangle(*(curr[0]), dir[event], *(curr[1]), *(curr[2]), *(curr[3]));
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for (;;) {
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if (++curr[event] == l)
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curr[event] = f;
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ForwardIterator cp = curr[event];
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if (++cp == l)
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|
cp = f;
|
||
|
|
||
|
dir[event] = rotate(direction(*(curr[event]), *cp), event);
|
||
|
|
||
|
if (curr[event] == limit[event])
|
||
|
if (--yet_to_finish <= 0)
|
||
|
break;
|
||
|
|
||
|
if (event < 2)
|
||
|
low = less_angle(dir[0], dir[1]) ? 0 : 1;
|
||
|
else
|
||
|
upp = less_angle(dir[2], dir[3]) ? 2 : 3;
|
||
|
|
||
|
event = less_angle(dir[low], dir[upp]) ? low : upp;
|
||
|
|
||
|
Rectangle_2 test_rect = rectangle(*(curr[0]), dir[event],
|
||
|
*(curr[1]), *(curr[2]), *(curr[3]));
|
||
|
if (area_less(test_rect, rect_so_far))
|
||
|
rect_so_far = test_rect;
|
||
|
|
||
|
} // for (;;)
|
||
|
|
||
|
return t.copy_rectangle_vertices_2(rect_so_far, o);
|
||
|
|
||
|
} // min_rectangle_2( f, l, o , t)
|
||
|
|
||
|
template < class ForwardIterator, class OutputIterator, class BTraits >
|
||
|
OutputIterator
|
||
|
min_parallelogram_2(ForwardIterator f,
|
||
|
ForwardIterator l,
|
||
|
OutputIterator o,
|
||
|
BTraits& bt)
|
||
|
{
|
||
|
typedef Optimisation::Min_quadrilateral_traits_wrapper<BTraits> Traits;
|
||
|
Traits t(bt);
|
||
|
CGAL_optimisation_expensive_precondition(is_convex_2(f, l, t));
|
||
|
|
||
|
// types from the traits class
|
||
|
typedef typename Traits::Direction_2 Direction_2;
|
||
|
typedef typename Traits::Parallelogram_2 Parallelogram_2;
|
||
|
typedef typename Traits::Construct_direction_2 Construct_direction_2;
|
||
|
typedef typename Traits::Equal_2 Equal_2;
|
||
|
|
||
|
Equal_2 equal = t.equal_2_object();
|
||
|
Construct_direction_2 direction = t.construct_direction_2_object();
|
||
|
typename Traits::Construct_parallelogram_2
|
||
|
parallelogram = t.construct_parallelogram_2_object();
|
||
|
typename Traits::Less_angle_with_x_axis_2
|
||
|
less_angle = t.less_angle_with_x_axis_2_object();
|
||
|
typename Traits::Area_less_parallelogram_2
|
||
|
area_less = t.area_less_parallelogram_2_object();
|
||
|
typename Traits::Right_of_implicit_line_2
|
||
|
right_of_line = t.right_of_implicit_line_2_object();
|
||
|
|
||
|
// check for trivial cases
|
||
|
if (f == l) return o;
|
||
|
|
||
|
ForwardIterator first;
|
||
|
do {
|
||
|
first = f;
|
||
|
if (++f == l) {
|
||
|
// all points are equal
|
||
|
for (int i = 0; i < 4; ++i) *o++ = *first;
|
||
|
return o;
|
||
|
}
|
||
|
} while (equal(*first, *f));
|
||
|
|
||
|
// quadruple of points defining the bounding box
|
||
|
ForwardIterator curr[4];
|
||
|
// initialised to the points defining the bounding box
|
||
|
convex_bounding_box_2(first, l, curr, t);
|
||
|
|
||
|
|
||
|
ForwardIterator low = curr[0];
|
||
|
ForwardIterator upp = curr[2];
|
||
|
ForwardIterator right = low;
|
||
|
ForwardIterator left = upp;
|
||
|
|
||
|
int yet_to_finish = 2;
|
||
|
|
||
|
// initialize parallelogram
|
||
|
ForwardIterator ln = low;
|
||
|
do
|
||
|
if (++ln == l)
|
||
|
ln = first;
|
||
|
while (equal(*ln, *low));
|
||
|
Direction_2 d_low = direction(*low, *ln);
|
||
|
ForwardIterator un = upp;
|
||
|
do
|
||
|
if (++un == l)
|
||
|
un = first;
|
||
|
while (equal(*un, *upp));
|
||
|
Direction_2 d_upp = direction(*un, *upp);
|
||
|
|
||
|
bool low_goes_next = less_angle(d_low, d_upp);
|
||
|
Direction_2 next_dir = low_goes_next ? d_low : d_upp;
|
||
|
|
||
|
Direction_2 d_leftright = next_dir;
|
||
|
for (;;) {
|
||
|
// compute the next left/right candidate and store it to d_leftright
|
||
|
ForwardIterator rig = right;
|
||
|
do
|
||
|
if (++rig == l)
|
||
|
rig = first;
|
||
|
while (equal(*rig, *right));
|
||
|
Direction_2 d_right = direction(*right, *rig);
|
||
|
|
||
|
ForwardIterator len = left;
|
||
|
do
|
||
|
if (++len == l)
|
||
|
len = first;
|
||
|
while (equal(*len, *left));
|
||
|
Direction_2 d_left = direction(*len, *left);
|
||
|
|
||
|
if (less_angle(d_right, d_left))
|
||
|
if (right_of_line(*rig, *left, next_dir))
|
||
|
right = rig;
|
||
|
else {
|
||
|
d_leftright = d_right;
|
||
|
break;
|
||
|
}
|
||
|
else
|
||
|
if (right_of_line(*right, *len, next_dir))
|
||
|
left = len;
|
||
|
else {
|
||
|
d_leftright = d_left;
|
||
|
break;
|
||
|
}
|
||
|
} // for (;;)
|
||
|
|
||
|
Parallelogram_2 para_so_far =
|
||
|
parallelogram(*low, next_dir, *right, d_leftright, *upp, *left);
|
||
|
|
||
|
for (;;) {
|
||
|
if (low_goes_next) {
|
||
|
low = ln;
|
||
|
if (low == curr[2])
|
||
|
if (--yet_to_finish <= 0)
|
||
|
break;
|
||
|
} else {
|
||
|
upp = un;
|
||
|
if (upp == curr[0])
|
||
|
if (--yet_to_finish <= 0)
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
// compute the next lower/upper candidate
|
||
|
ln = low;
|
||
|
do
|
||
|
if (++ln == l)
|
||
|
ln = first;
|
||
|
while (equal(*ln, *low));
|
||
|
d_low = direction(*low, *ln);
|
||
|
un = upp;
|
||
|
do
|
||
|
if (++un == l)
|
||
|
un = first;
|
||
|
while (equal(*un, *upp));
|
||
|
d_upp = direction(*un, *upp);
|
||
|
|
||
|
low_goes_next = less_angle(d_low, d_upp);
|
||
|
next_dir = low_goes_next ? d_low : d_upp;
|
||
|
|
||
|
for (;;) {
|
||
|
// compute the next left/right candidate and store it to d_leftright
|
||
|
ForwardIterator rig = right;
|
||
|
do
|
||
|
if (++rig == l)
|
||
|
rig = first;
|
||
|
while (equal(*rig, *right));
|
||
|
Direction_2 d_right = direction(*right, *rig);
|
||
|
|
||
|
ForwardIterator len = left;
|
||
|
do
|
||
|
if (++len == l)
|
||
|
len = first;
|
||
|
while (equal(*len, *left));
|
||
|
Direction_2 d_left = direction(*len, *left);
|
||
|
|
||
|
if (less_angle(d_right, d_left))
|
||
|
if (right_of_line(*rig, *left, next_dir))
|
||
|
right = rig;
|
||
|
else {
|
||
|
d_leftright = d_right;
|
||
|
break;
|
||
|
}
|
||
|
else
|
||
|
if (right_of_line(*right, *len, next_dir))
|
||
|
left = len;
|
||
|
else {
|
||
|
d_leftright = d_left;
|
||
|
break;
|
||
|
}
|
||
|
} // for (;;)
|
||
|
|
||
|
// check whether we found a smaller parallelogram
|
||
|
Parallelogram_2 test_para =
|
||
|
parallelogram(*low, next_dir, *right, d_leftright, *upp, *left);
|
||
|
|
||
|
|
||
|
if (area_less(test_para, para_so_far))
|
||
|
para_so_far = test_para;
|
||
|
|
||
|
} // for (;;)
|
||
|
|
||
|
|
||
|
return t.copy_parallelogram_vertices_2(para_so_far, o);
|
||
|
} // min_parallelogram_2(f, l, o , t)
|
||
|
template < class ForwardIterator, class OutputIterator, class BTraits >
|
||
|
OutputIterator
|
||
|
min_strip_2(ForwardIterator f,
|
||
|
ForwardIterator l,
|
||
|
OutputIterator o,
|
||
|
BTraits& bt)
|
||
|
{
|
||
|
typedef Optimisation::Min_quadrilateral_traits_wrapper<BTraits> Traits;
|
||
|
Traits t(bt);
|
||
|
CGAL_optimisation_expensive_precondition(is_convex_2(f, l, t));
|
||
|
|
||
|
// types from the traits class
|
||
|
typedef typename Traits::Direction_2 Direction_2;
|
||
|
typedef typename Traits::Strip_2 Strip_2;
|
||
|
typedef typename Traits::Equal_2 Equal_2;
|
||
|
typedef typename Traits::Construct_direction_2 Construct_direction_2;
|
||
|
typedef typename Traits::Construct_strip_2 Construct_strip_2;
|
||
|
typedef typename Traits::Width_less_strip_2 Width_less_strip_2;
|
||
|
|
||
|
Equal_2 equal = t.equal_2_object();
|
||
|
Construct_direction_2 direction = t.construct_direction_2_object();
|
||
|
Construct_strip_2 strip = t.construct_strip_2_object();
|
||
|
Width_less_strip_2 width_less = t.width_less_strip_2_object();
|
||
|
typename Traits::Less_angle_with_x_axis_2
|
||
|
less_angle = t.less_angle_with_x_axis_2_object();
|
||
|
|
||
|
// check for trivial cases
|
||
|
if (f == l) return o;
|
||
|
ForwardIterator first;
|
||
|
do {
|
||
|
first = f;
|
||
|
if (++f == l)
|
||
|
// strip undefined, if no two distinct points exist
|
||
|
return o;
|
||
|
} while (equal(*first, *f));
|
||
|
|
||
|
// quadruple of points defining the bounding box
|
||
|
ForwardIterator curr[4];
|
||
|
// initialised to the points defining the bounding box
|
||
|
convex_bounding_box_2(first, l, curr, t);
|
||
|
|
||
|
ForwardIterator low = curr[0];
|
||
|
ForwardIterator upp = curr[2];
|
||
|
|
||
|
int yet_to_finish = 2;
|
||
|
|
||
|
ForwardIterator nlow = low;
|
||
|
if (++nlow == l)
|
||
|
nlow = first;
|
||
|
Direction_2 low_dir = direction(*low, *nlow);
|
||
|
ForwardIterator nupp = upp;
|
||
|
if (++nupp == l)
|
||
|
nupp = first;
|
||
|
Direction_2 upp_dir = direction(*nupp, *upp);
|
||
|
|
||
|
bool low_goes_next = less_angle(low_dir, upp_dir);
|
||
|
Strip_2 strip_so_far = low_goes_next ?
|
||
|
strip(*low, low_dir, *upp) : strip(*low, upp_dir, *upp);
|
||
|
|
||
|
for (;;) {
|
||
|
// compute next direction
|
||
|
if (low_goes_next) {
|
||
|
low = nlow;
|
||
|
if (low == curr[2])
|
||
|
if (--yet_to_finish <= 0)
|
||
|
break;
|
||
|
if (++nlow == l)
|
||
|
nlow = first;
|
||
|
low_dir = direction(*low, *nlow);
|
||
|
} else {
|
||
|
upp = nupp;
|
||
|
if (upp == curr[0])
|
||
|
if (--yet_to_finish <= 0)
|
||
|
break;
|
||
|
if (++nupp == l)
|
||
|
nupp = first;
|
||
|
upp_dir = direction(*nupp, *upp);
|
||
|
}
|
||
|
|
||
|
low_goes_next = less_angle(low_dir, upp_dir);
|
||
|
Strip_2 test_strip = low_goes_next ?
|
||
|
strip(*low, low_dir, *upp) : strip(*low, upp_dir, *upp);
|
||
|
if (width_less(test_strip, strip_so_far))
|
||
|
strip_so_far = test_strip;
|
||
|
|
||
|
} // for (;;)
|
||
|
|
||
|
// return the result
|
||
|
return t.copy_strip_lines_2(strip_so_far, o);
|
||
|
|
||
|
} // min_strip_2(f, l, o, t)
|
||
|
|
||
|
|
||
|
} //namespace CGAL
|
||
|
#include <CGAL/Min_quadrilateral_traits_2.h>
|
||
|
namespace CGAL {
|
||
|
|
||
|
template < class ForwardIterator, class OutputIterator >
|
||
|
inline
|
||
|
OutputIterator
|
||
|
min_rectangle_2(ForwardIterator f,
|
||
|
ForwardIterator l,
|
||
|
OutputIterator o)
|
||
|
{
|
||
|
typedef typename std::iterator_traits< ForwardIterator >::value_type VT;
|
||
|
typedef typename Kernel_traits<VT>::Kernel Kernel;
|
||
|
Min_quadrilateral_default_traits_2<Kernel> t;
|
||
|
return min_rectangle_2(f, l, o, t);
|
||
|
} // min_rectangle_2(f, l, o)
|
||
|
|
||
|
#ifndef CGAL_NO_DEPRECATED_CODE
|
||
|
// backwards compatibility
|
||
|
template < class ForwardIterator, class OutputIterator >
|
||
|
inline
|
||
|
OutputIterator
|
||
|
minimum_enclosing_rectangle_2(ForwardIterator f,
|
||
|
ForwardIterator l,
|
||
|
OutputIterator o)
|
||
|
{ return min_rectangle_2(f, l, o); }
|
||
|
#endif // CGAL_NO_DEPRECATED_CODE
|
||
|
template < class ForwardIterator, class OutputIterator >
|
||
|
inline
|
||
|
OutputIterator
|
||
|
min_parallelogram_2(ForwardIterator f,
|
||
|
ForwardIterator l,
|
||
|
OutputIterator o)
|
||
|
{
|
||
|
typedef typename std::iterator_traits< ForwardIterator >::value_type VT;
|
||
|
typedef typename Kernel_traits<VT>::Kernel Kernel;
|
||
|
Min_quadrilateral_default_traits_2<Kernel> t;
|
||
|
return min_parallelogram_2(f, l, o, t);
|
||
|
} // min_parallelogram_2(f, l, o)
|
||
|
|
||
|
#ifndef CGAL_NO_DEPRECATED_CODE
|
||
|
// backwards compatibility
|
||
|
template < class ForwardIterator, class OutputIterator >
|
||
|
inline
|
||
|
OutputIterator
|
||
|
minimum_enclosing_parallelogram_2(ForwardIterator f,
|
||
|
ForwardIterator l,
|
||
|
OutputIterator o)
|
||
|
{ return min_parallelogram_2(f, l, o); }
|
||
|
#endif // CGAL_NO_DEPRECATED_CODE
|
||
|
template < class ForwardIterator, class OutputIterator >
|
||
|
inline
|
||
|
OutputIterator
|
||
|
min_strip_2(ForwardIterator f,
|
||
|
ForwardIterator l,
|
||
|
OutputIterator o)
|
||
|
{
|
||
|
typedef typename std::iterator_traits< ForwardIterator >::value_type VT;
|
||
|
typedef typename Kernel_traits<VT>::Kernel Kernel;
|
||
|
Min_quadrilateral_default_traits_2<Kernel> t;
|
||
|
return min_strip_2(f, l, o, t);
|
||
|
} // min_strip_2(f, l, o)
|
||
|
|
||
|
#ifndef CGAL_NO_DEPRECATED_CODE
|
||
|
// backwards compatibility
|
||
|
template < class ForwardIterator, class OutputIterator >
|
||
|
inline
|
||
|
OutputIterator
|
||
|
minimum_enclosing_strip_2(ForwardIterator f,
|
||
|
ForwardIterator l,
|
||
|
OutputIterator o)
|
||
|
{ return min_strip_2(f, l, o); }
|
||
|
#endif // CGAL_NO_DEPRECATED_CODE
|
||
|
|
||
|
} //namespace CGAL
|
||
|
|
||
|
#endif // ! (CGAL_MIN_QUADRILATERAL_2_H)
|