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diff --git a/src/2geom/svg-path-writer.cpp b/src/2geom/svg-path-writer.cpp
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+/** @file
+ * @brief Path sink which writes an SVG-compatible command string
+ *//*
+ * Authors:
+ * Krzysztof Kosiński <tweenk.pl@gmail.com>
+ *
+ * Copyright 2014 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.
+ */
+
+#include <cmath>
+#include <iomanip>
+#include <2geom/coord.h>
+#include <2geom/svg-path-writer.h>
+#include <glib.h>
+
+namespace Geom {
+
+static inline bool is_digit(char c) {
+ return c >= '0' && c <= '9';
+}
+
+SVGPathWriter::SVGPathWriter()
+ : _epsilon(0)
+ , _precision(-1)
+ , _optimize(false)
+ , _use_shorthands(true)
+ , _command(0)
+{
+ // always use C locale for number formatting
+ _ns.imbue(std::locale::classic());
+ _ns.unsetf(std::ios::floatfield);
+}
+
+void SVGPathWriter::moveTo(Point const &p)
+{
+ _setCommand('M');
+ _current_pars.push_back(p[X]);
+ _current_pars.push_back(p[Y]);
+
+ _current = _subpath_start = _quad_tangent = _cubic_tangent = p;
+ if (!_optimize) {
+ flush();
+ }
+}
+
+void SVGPathWriter::lineTo(Point const &p)
+{
+ // The weird setting of _current is to avoid drift with many almost-aligned segments
+ // The additional conditions ensure that the smaller dimension is rounded to zero
+ bool written = false;
+ if (_use_shorthands) {
+ Point r = _current - p;
+ if (are_near(p[X], _current[X], _epsilon) && std::abs(r[X]) < std::abs(r[Y])) {
+ // emit vlineto
+ _setCommand('V');
+ _current_pars.push_back(p[Y]);
+ _current[Y] = p[Y];
+ written = true;
+ } else if (are_near(p[Y], _current[Y], _epsilon) && std::abs(r[Y]) < std::abs(r[X])) {
+ // emit hlineto
+ _setCommand('H');
+ _current_pars.push_back(p[X]);
+ _current[X] = p[X];
+ written = true;
+ }
+ }
+
+ if (!written) {
+ // emit normal lineto
+ if (_command != 'M' && _command != 'L') {
+ _setCommand('L');
+ }
+ _current_pars.push_back(p[X]);
+ _current_pars.push_back(p[Y]);
+ _current = p;
+ }
+
+ _cubic_tangent = _quad_tangent = _current;
+ if (!_optimize) {
+ flush();
+ }
+}
+
+void SVGPathWriter::quadTo(Point const &c, Point const &p)
+{
+ bool shorthand = _use_shorthands && are_near(c, _quad_tangent, _epsilon);
+
+ _setCommand(shorthand ? 'T' : 'Q');
+ if (!shorthand) {
+ _current_pars.push_back(c[X]);
+ _current_pars.push_back(c[Y]);
+ }
+ _current_pars.push_back(p[X]);
+ _current_pars.push_back(p[Y]);
+
+ _current = _cubic_tangent = p;
+ _quad_tangent = p + (p - c);
+ if (!_optimize) {
+ flush();
+ }
+}
+
+void SVGPathWriter::curveTo(Point const &p1, Point const &p2, Point const &p3)
+{
+ bool shorthand = _use_shorthands && are_near(p1, _cubic_tangent, _epsilon);
+
+ _setCommand(shorthand ? 'S' : 'C');
+ if (!shorthand) {
+ _current_pars.push_back(p1[X]);
+ _current_pars.push_back(p1[Y]);
+ }
+ _current_pars.push_back(p2[X]);
+ _current_pars.push_back(p2[Y]);
+ _current_pars.push_back(p3[X]);
+ _current_pars.push_back(p3[Y]);
+
+ _current = _quad_tangent = p3;
+ _cubic_tangent = p3 + (p3 - p2);
+ if (!_optimize) {
+ flush();
+ }
+}
+
+void SVGPathWriter::arcTo(double rx, double ry, double angle,
+ bool large_arc, bool sweep, Point const &p)
+{
+ _setCommand('A');
+ _current_pars.push_back(rx);
+ _current_pars.push_back(ry);
+ _current_pars.push_back(deg_from_rad(angle));
+ _current_pars.push_back(large_arc ? 1. : 0.);
+ _current_pars.push_back(sweep ? 1. : 0.);
+ _current_pars.push_back(p[X]);
+ _current_pars.push_back(p[Y]);
+
+ _current = _quad_tangent = _cubic_tangent = p;
+ if (!_optimize) {
+ flush();
+ }
+}
+
+void SVGPathWriter::closePath()
+{
+ flush();
+ if (_optimize) {
+ _s << "z";
+ } else {
+ _s << " z";
+ }
+ _current = _quad_tangent = _cubic_tangent = _subpath_start;
+}
+
+void SVGPathWriter::flush()
+{
+ if (_command == 0 || _current_pars.empty()) return;
+
+ if (_optimize) {
+ _s << _command;
+ } else {
+ if (_s.tellp() != 0) {
+ _s << ' ';
+ }
+ _s << _command;
+ }
+
+ char lastchar = _command;
+ bool contained_dot = false;
+
+ for (double _current_par : _current_pars) {
+ // TODO: optimize the use of absolute / relative coords
+ std::string cs = _formatCoord(_current_par);
+
+ // Separator handling logic.
+ // Floating point values can end with a digit or dot
+ // and start with a digit, a plus or minus sign, or a dot.
+ // The following cases require a separator:
+ // * digit-digit
+ // * digit-dot (only if the previous number didn't contain a dot)
+ // * dot-digit
+ if (_optimize) {
+ // C++11: change to front()
+ char firstchar = cs[0];
+ if (is_digit(lastchar)) {
+ if (is_digit(firstchar)) {
+ _s << " ";
+ } else if (firstchar == '.' && !contained_dot) {
+ _s << " ";
+ }
+ } else if (lastchar == '.' && is_digit(firstchar)) {
+ _s << " ";
+ }
+ _s << cs;
+
+ // C++11: change to back()
+ lastchar = cs[cs.length()-1];
+ contained_dot = cs.find('.') != std::string::npos;
+ } else {
+ _s << " " << cs;
+ }
+ }
+ _current_pars.clear();
+ _command = 0;
+}
+
+void SVGPathWriter::clear()
+{
+ _s.clear();
+ _s.str("");
+ _ns.clear();
+ _ns.str("");
+ _command = 0;
+ _current_pars.clear();
+ _current = Point(0,0);
+ _subpath_start = Point(0,0);
+}
+
+void SVGPathWriter::setPrecision(int prec)
+{
+ _precision = prec;
+ if (prec < 0) {
+ _epsilon = 0;
+ } else {
+ _epsilon = std::pow(10., -prec);
+ _ns << std::setprecision(_precision);
+ }
+}
+
+void SVGPathWriter::_setCommand(char cmd)
+{
+ if (_command != 0 && _command != cmd) {
+ flush();
+ }
+ _command = cmd;
+}
+
+std::string SVGPathWriter::_formatCoord(Coord par)
+{
+ std::string ret;
+ if (_precision < 0) {
+ ret = format_coord_shortest(par);
+ } else {
+ _ns << par;
+ ret = _ns.str();
+ _ns.clear();
+ _ns.str("");
+ }
+ return ret;
+}
+
+
+std::string write_svg_path(PathVector const &pv, int prec, bool optimize, bool shorthands)
+{
+ SVGPathWriter writer;
+ writer.setPrecision(prec);
+ writer.setOptimize(optimize);
+ writer.setUseShorthands(shorthands);
+
+ writer.feed(pv);
+ return writer.str();
+}
+
+} // namespace Geom
+
+/*
+ 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:fileencoding=utf-8:textwidth=99 :
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