/** * \file * \brief nearest point routines for D2 and Piecewise> * * Authors: * * Marco Cecchetti * * Copyright 2007-2008 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 _NEAREST_POINT_H_ #define _NEAREST_POINT_H_ #include #include <2geom/d2.h> #include <2geom/piecewise.h> #include <2geom/exception.h> namespace Geom { /* * Given a line L specified by a point A and direction vector v, * return the point on L nearest to p. Note that the returned value * is with respect to the _normalized_ direction of v! */ inline double nearest_point(Point const &p, Point const &A, Point const &v) { Point d(p - A); return d[0] * v[0] + d[1] * v[1]; } //////////////////////////////////////////////////////////////////////////////// // D2 versions /* * Return the parameter t of a nearest point on the portion of the curve "c", * related to the interval [from, to], to the point "p". * The needed curve derivative "dc" is passed as parameter. * The function return the first nearest point to "p" that is found. */ double nearest_point( Point const& p, D2 const& c, D2 const& dc, double from = 0, double to = 1 ); inline double nearest_point( Point const& p, D2 const& c, double from = 0, double to = 1 ) { return nearest_point(p, c, Geom::derivative(c), from, to); } /* * Return the parameters t of all the nearest points on the portion of * the curve "c", related to the interval [from, to], to the point "p". * The needed curve derivative "dc" is passed as parameter. */ std::vector all_nearest_points( Point const& p, D2 const& c, D2 const& dc, double from = 0, double to = 1 ); inline std::vector all_nearest_points( Point const& p, D2 const& c, double from = 0, double to = 1 ) { return all_nearest_points(p, c, Geom::derivative(c), from, to); } //////////////////////////////////////////////////////////////////////////////// // Piecewise< D2 > versions double nearest_point( Point const& p, Piecewise< D2 > const& c, double from, double to ); inline double nearest_point( Point const& p, Piecewise< D2 > const& c ) { return nearest_point(p, c, c.cuts[0], c.cuts[c.size()]); } std::vector all_nearest_points( Point const& p, Piecewise< D2 > const& c, double from, double to ); inline std::vector all_nearest_points( Point const& p, Piecewise< D2 > const& c ) { return all_nearest_points(p, c, c.cuts[0], c.cuts[c.size()]); } } // end namespace Geom #endif /*_NEAREST_POINT_H_*/