dust3d/thirdparty/cgal/CGAL-4.13/include/CGAL/Minkowski_sum_2/Labels.h

293 lines
6.8 KiB
C++
Executable File

// Copyright (c) 2006 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
// General Public License as published by the Free Software Foundation,
// either version 3 of the License, or (at your option) any later version.
//
// 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.
//
// $URL$
// $Id$
// SPDX-License-Identifier: GPL-3.0+
//
// Author(s) : Ron Wein <wein_r@yahoo.com>
#ifndef CGAL_MINKOWSKI_SUM_LABELS_H
#define CGAL_MINKOWSKI_SUM_LABELS_H
#include <CGAL/license/Minkowski_sum_2.h>
namespace CGAL {
/*! \class
* A label for endpoints of Minkowski-sum curves.
*/
class Point_label
{
private:
unsigned int _component; // The index of the component this point
// belongs to.
unsigned int _index; // Index of the point in the component.
public:
/*! Default constructor. */
Point_label () :
_component (0),
_index (0)
{}
/*!
* Constructor.
* \param component The index of the component.
* \param index Index of the point within the component.
*/
Point_label (unsigned int component,
unsigned int index) :
_component (component),
_index (index)
{
CGAL_precondition (component != 0);
}
/*! Check whether the label is valid. */
bool is_valid () const
{
return (_component != 0);
}
/*! Check two labels for equality. */
bool operator== (const Point_label& label) const
{
if (_component == 0 || label._component == 0)
return (false);
return (_component == label._component &&
_index == label._index);
}
/*! Get the component. */
unsigned int component () const
{
return (_component);
}
/*! Get the index within the component. */
unsigned int index () const
{
return (_index);
}
/*! Set the component. */
void set_component (unsigned int component)
{
CGAL_precondition (component != 0);
_component = component;
return;
}
/*! Set the index. */
void set_index (unsigned int index)
{
_index = index;
return;
}
};
/*! \class
* A label for Minkowski-sum x-monotone curves.
*/
class X_curve_label
{
private:
unsigned int _component; // The index of the component the x-monotone
// curve belongs to.
unsigned int _index; // Index of the curve in the component.
bool _is_last; // Is the curve the last one in its component.
int _right; // The number of curves directed from left to
// right that are associated with the curve.
int _left; // The number of curves directed from right to
// left that are associated with the curve.
public:
/*! Default constructor. */
X_curve_label () :
_component (0),
_index (0),
_is_last (false),
_right (0),
_left (0)
{}
/*!
* Constructor.
* \param is_directed_right Is the curve directed from left to right.
* \param component The index of the component.
* \param index Index of the curve in the component.
* \param is_last Is this the last curve of the component.
*/
X_curve_label (bool is_directed_right,
unsigned int component,
unsigned int index,
bool is_last = false) :
_component (component),
_index (index),
_is_last (is_last),
_right (is_directed_right ? 1 : 0),
_left (is_directed_right ? 0 : 1)
{
CGAL_precondition (component != 0);
}
/*!
* Construct a merged curve label.
* \param label1 The first label.
* \param label2 The second label.
*/
X_curve_label (const X_curve_label& label1,
const X_curve_label& label2) :
_component (0),
_index (0),
_is_last (false),
_right (label1._right + label2._right),
_left (label1._left + label2._left)
{}
/*! Check whether the label is valid. */
bool is_valid () const
{
return (_component != 0);
}
/*! Check two labels for equality. */
bool operator== (const X_curve_label& label) const
{
if (_component == 0)
return (false);
return (_component == label._component &&
_index == label._index);
}
/*! Check whether the given label is the predecessor of this label. */
bool is_prev (const X_curve_label& label) const
{
if (_component == 0)
return (false);
return (_component == label._component &&
(label._index + 1 == _index ||
(label._is_last && _index == 0)));
}
/*! Check whether the given label is the succcessor of this label. */
bool is_next (const X_curve_label& label) const
{
if (_component == 0)
return (false);
return (_component == label._component &&
(_index + 1 == label._index ||
(_is_last && label._index == 0)));
}
/*!
* Check if the given label is the successor of this label
* (or vice-versa).
*/
bool is_adjacent (const X_curve_label& label) const
{
if (_component == 0)
return (false);
// Two curves can be adjacent only if they belong to the same component.
if (_component != label._component)
return (false);
// Check if one label is adjacent to the next.
return ((_index + 1 == label._index) ||
(label._index + 1 == _index) ||
(_is_last && label._index == 0) ||
(label._is_last && _index == 0));
}
/*! Get the number of curves directed from left to right. */
int right_count () const
{
return (_right);
}
/*! Get the number of curves directed from right to left. */
int left_count () const
{
return (_left);
}
/*! Get the component. */
unsigned int component () const
{
return (_component);
}
/*! Get the index within the component. */
unsigned int index () const
{
return (_index);
}
/*! Check whether this is the last curve in the component. */
bool is_last () const
{
return (_is_last);
}
/*! Set the component. */
void set_component (unsigned int component)
{
CGAL_precondition (component != 0);
_component = component;
return;
}
/*!
* Set the curve index within the component.
* \param index The index in the component.
* \param is_last Is this the last curve of the component.
*/
void set_index (unsigned int index, bool is_last = false)
{
_index = index;
_is_last = is_last;
return;
}
/*! Get the flag value. */
bool get_flag () const
{
return (_is_last);
}
/*! Set the flag value. */
void set_flag (bool flag)
{
_is_last = flag;
return;
}
};
} //namespace CGAL
#endif