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Diffstat (limited to 'src/svg/path-string.cpp')
-rw-r--r-- | src/svg/path-string.cpp | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/src/svg/path-string.cpp b/src/svg/path-string.cpp new file mode 100644 index 0000000..516fe35 --- /dev/null +++ b/src/svg/path-string.cpp @@ -0,0 +1,167 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/** @file + * Inkscape::SVG::PathString - builder for SVG path strings + *//* + * Authors: see git history + * + * Copyright 2008 Jasper van de Gronde <th.v.d.gronde@hccnet.nl> + * Copyright 2013 Tavmjong Bah <tavmjong@free.fr> + * Copyright (C) 2018 Authors + * + * Released under GNU GPL v2+, read the file 'COPYING' for more information. + */ + +#include "svg/path-string.h" +#include "svg/stringstream.h" +#include "svg/svg.h" +#include "preferences.h" + +// 1<=numericprecision<=16, doubles are only accurate upto (slightly less than) 16 digits (and less than one digit doesn't make sense) +// Please note that these constants are used to allocate sufficient space to hold serialized numbers +static int const minprec = 1; +static int const maxprec = 16; + +int Inkscape::SVG::PathString::numericprecision; +int Inkscape::SVG::PathString::minimumexponent; +Inkscape::SVG::PATHSTRING_FORMAT Inkscape::SVG::PathString::format; + +Inkscape::SVG::PathString::PathString() : + force_repeat_commands(!Inkscape::Preferences::get()->getBool("/options/svgoutput/disable_optimizations" ) && Inkscape::Preferences::get()->getBool("/options/svgoutput/forcerepeatcommands")) +{ + Inkscape::Preferences *prefs = Inkscape::Preferences::get(); + format = (PATHSTRING_FORMAT)prefs->getIntLimited("/options/svgoutput/pathstring_format", 1, 0, PATHSTRING_FORMAT_SIZE - 1 ); + numericprecision = std::max<int>(minprec,std::min<int>(maxprec, prefs->getInt("/options/svgoutput/numericprecision", 8))); + minimumexponent = prefs->getInt("/options/svgoutput/minimumexponent", -8); +} + +// For absolute and relative paths... the entire path is kept in the "tail". +// For optimized path, at a switch between absolute and relative, add tail to commonbase. +void Inkscape::SVG::PathString::_appendOp(char abs_op, char rel_op) { + bool abs_op_repeated = _abs_state.prevop == abs_op && !force_repeat_commands; + bool rel_op_repeated = _rel_state.prevop == rel_op && !force_repeat_commands; + + // For absolute and relative paths... do nothing. + switch (format) { + case PATHSTRING_ABSOLUTE: + if ( !abs_op_repeated ) _abs_state.appendOp(abs_op); + break; + case PATHSTRING_RELATIVE: + if ( !rel_op_repeated ) _rel_state.appendOp(rel_op); + break; + case PATHSTRING_OPTIMIZE: + { + unsigned int const abs_added_size = abs_op_repeated ? 0 : 2; + unsigned int const rel_added_size = rel_op_repeated ? 0 : 2; + if ( _rel_state.str.size()+2 < _abs_state.str.size()+abs_added_size ) { + + // Store common prefix + commonbase += _rel_state.str; + _rel_state.str.clear(); + // Copy rel to abs + _abs_state = _rel_state; + _abs_state.switches++; + abs_op_repeated = false; + // We do not have to copy abs to rel: + // _rel_state.str.size()+2 < _abs_state.str.size()+abs_added_size + // _rel_state.str.size()+rel_added_size < _abs_state.str.size()+2 + // _abs_state.str.size()+2 > _rel_state.str.size()+rel_added_size + } else if ( _abs_state.str.size()+2 < _rel_state.str.size()+rel_added_size ) { + + // Store common prefix + commonbase += _abs_state.str; + _abs_state.str.clear(); + // Copy abs to rel + _rel_state = _abs_state; + _abs_state.switches++; + rel_op_repeated = false; + } + if ( !abs_op_repeated ) _abs_state.appendOp(abs_op); + if ( !rel_op_repeated ) _rel_state.appendOp(rel_op); + } + break; + default: + std::cout << "Better not be here!" << std::endl; + } +} + +void Inkscape::SVG::PathString::State::append(Geom::Coord v) { + str += ' '; + appendNumber(v); +} + +void Inkscape::SVG::PathString::State::append(Geom::Point p) { + str += ' '; + appendNumber(p[Geom::X]); + str += ','; + appendNumber(p[Geom::Y]); +} + +void Inkscape::SVG::PathString::State::append(Geom::Coord v, Geom::Coord& rv) { + str += ' '; + appendNumber(v, rv); +} + +void Inkscape::SVG::PathString::State::append(Geom::Point p, Geom::Point &rp) { + str += ' '; + appendNumber(p[Geom::X], rp[Geom::X]); + str += ','; + appendNumber(p[Geom::Y], rp[Geom::Y]); +} + +// NOTE: The following appendRelativeCoord function will not be exact if the total number of digits needed +// to represent the difference exceeds the precision of a double. This is not very likely though, and if +// it does happen the imprecise value is not likely to be chosen (because it will probably be a lot longer +// than the absolute value). + +// NOTE: This assumes v and r are already rounded (this includes flushing to zero if they are < 10^minexp) +void Inkscape::SVG::PathString::State::appendRelativeCoord(Geom::Coord v, Geom::Coord r) { + int const minexp = minimumexponent-numericprecision+1; + int const digitsEnd = (int)floor(log10(std::min(fabs(v),fabs(r)))) - numericprecision; // Position just beyond the last significant digit of the smallest (in absolute sense) number + double const roundeddiff = floor((v-r)*pow(10.,-digitsEnd-1)+.5); + int const numDigits = (int)floor(log10(fabs(roundeddiff)))+1; // Number of digits in roundeddiff + if (r == 0) { + appendNumber(v, numericprecision, minexp); + } else if (v == 0) { + appendNumber(-r, numericprecision, minexp); + } else if (numDigits>0) { + appendNumber(v-r, numDigits, minexp); + } else { + // This assumes the input numbers are already rounded to 'precision' digits + str += '0'; + } +} + +void Inkscape::SVG::PathString::State::appendRelative(Geom::Point p, Geom::Point r) { + str += ' '; + appendRelativeCoord(p[Geom::X], r[Geom::X]); + str += ','; + appendRelativeCoord(p[Geom::Y], r[Geom::Y]); +} + +void Inkscape::SVG::PathString::State::appendRelative(Geom::Coord v, Geom::Coord r) { + str += ' '; + appendRelativeCoord(v, r); +} + +void Inkscape::SVG::PathString::State::appendNumber(double v, int precision, int minexp) { + + str.append(sp_svg_number_write_de(v, precision, minexp)); +} + +void Inkscape::SVG::PathString::State::appendNumber(double v, double &rv, int precision, int minexp) { + size_t const oldsize = str.size(); + appendNumber(v, precision, minexp); + char* begin_of_num = const_cast<char*>(str.data()+oldsize); // Slightly evil, I know (but std::string should be storing its data in one big block of memory, so...) + sp_svg_number_read_d(begin_of_num, &rv); +} + +/* + 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 : |