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Diffstat (limited to 'src/2geom/intersection-graph.h')
| -rw-r--r-- | src/2geom/intersection-graph.h | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/src/2geom/intersection-graph.h b/src/2geom/intersection-graph.h new file mode 100644 index 000000000..bd9aaee81 --- /dev/null +++ b/src/2geom/intersection-graph.h @@ -0,0 +1,128 @@ +/** + * \file + * \brief Path intersection graph + *//* + * Authors: + * Krzysztof Kosiński <tweenk.pl@gmail.com> + * + * Copyright 2015 Authors + * + * This library is free software; you can redistribute it and/or + * modify it either under the terms of the GNU Lesser General Public + * License version 2.1 as published by the Free Software Foundation + * (the "LGPL") or, at your option, under the terms of the Mozilla + * Public License Version 1.1 (the "MPL"). If you do not alter this + * notice, a recipient may use your version of this file under either + * the MPL or the LGPL. + * + * You should have received a copy of the LGPL along with this library + * in the file COPYING-LGPL-2.1; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * You should have received a copy of the MPL along with this library + * in the file COPYING-MPL-1.1 + * + * The contents of this file are subject to the Mozilla Public License + * Version 1.1 (the "License"); you may not use this file except in + * compliance with the License. You may obtain a copy of the License at + * http://www.mozilla.org/MPL/ + * + * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY + * OF ANY KIND, either express or implied. See the LGPL or the MPL for + * the specific language governing rights and limitations. + */ + +#ifndef SEEN_LIB2GEOM_INTERSECTION_GRAPH_H +#define SEEN_LIB2GEOM_INTERSECTION_GRAPH_H + +#include <set> +#include <vector> +#include <boost/ptr_container/ptr_vector.hpp> +#include <boost/intrusive/list.hpp> +#include <2geom/forward.h> +#include <2geom/pathvector.h> + +namespace Geom { + +class PathIntersectionGraph +{ + // this is called PathIntersectionGraph so that we can also have a class for polygons, + // e.g. PolygonIntersectionGraph, which is going to be significantly faster +public: + PathIntersectionGraph(PathVector const &a, PathVector const &b, Coord precision = EPSILON); + + PathVector getUnion(); + PathVector getIntersection(); + PathVector getAminusB(); + PathVector getBminusA(); + PathVector getXOR(); + + /// Returns the number of intersections used when computing Boolean operations. + std::size_t size() const; + std::vector<Point> intersectionPoints() const; + +private: + enum InOutFlag { + POINT_INSIDE, + POINT_OUTSIDE + }; + + struct IntersectionVertex { + boost::intrusive::list_member_hook<> _hook; + PathVectorTime pos; + Point p; // guarantees that endpoints are exact + IntersectionVertex *neighbor; + bool entry; // going in +t direction enters the other path + InOutFlag previous; + InOutFlag next; + bool processed; // TODO: use intrusive unprocessed list instead + }; + + typedef boost::intrusive::list + < IntersectionVertex + , boost::intrusive::member_hook + < IntersectionVertex + , boost::intrusive::list_member_hook<> + , &IntersectionVertex::_hook + > + > IntersectionList; + + struct PathData { + IntersectionList xlist; + unsigned removed_in; + unsigned removed_out; + + PathData() + : removed_in(0) + , removed_out(0) + {} + }; + + struct IntersectionVertexLess; + + PathVector _getResult(bool enter_a, bool enter_b); + void _handleNonintersectingPaths(PathVector &result, int which, bool inside); + bool _findUnprocessed(IntersectionList::iterator &result); + + PathVector _a, _b; + boost::ptr_vector<IntersectionVertex> _xs; + boost::ptr_vector<PathData> _apaths; + boost::ptr_vector<PathData> _bpaths; + + friend std::ostream &operator<<(std::ostream &, PathIntersectionGraph const &); +}; + +std::ostream &operator<<(std::ostream &os, PathIntersectionGraph const &pig); + +} // namespace Geom + +#endif // SEEN_LIB2GEOM_PATH_GRAPH_H +/* + Local Variables: + mode:c++ + c-file-style:"stroustrup" + c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +)) + indent-tabs-mode:nil + fill-column:99 + End: +*/ +// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 : |