1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
|
/*
* Inkscape::SVG::PathString - builder for SVG path strings
*
* Copyright 2008 Jasper van de Gronde <th.v.d.gronde@hccnet.nl>
*
* This program is free software; 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 2
* of the License, or (at your option) any later version.
*
* See the file COPYING for details.
*
*/
#include "svg/path-string.h"
#include "svg/stringstream.h"
#include "svg/svg.h"
#include "preferences.h"
#include <algorithm>
// 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;
double Inkscape::SVG::PathString::epsilon;
Inkscape::SVG::PathString::PathString() :
allow_relative_coordinates(Inkscape::Preferences::get()->getBool("/options/svgoutput/allowrelativecoordinates", true)),
force_repeat_commands(Inkscape::Preferences::get()->getBool("/options/svgoutput/forcerepeatcommands")),
allow_shorthands(Inkscape::Preferences::get()->getBool("/options/svgoutput/allowshorthands", true))
{
Inkscape::Preferences *prefs = Inkscape::Preferences::get();
numericprecision = std::max<int>(minprec,std::min<int>(maxprec, prefs->getInt("/options/svgoutput/numericprecision", 8)));
minimumexponent = prefs->getInt("/options/svgoutput/minimumexponent", -8);
epsilon = pow(10, -numericprecision+1); // The +1 is to give a bit more headroom when we have "low" values (we use relative error, while really we should look at digits, so a number starting with 1 requires a tolerance that's about 10 times higher).
}
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;
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 && allow_relative_coordinates ) {
// 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);
}
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) {
size_t const reserve = precision+1+1+1+1+3; // Just large enough to hold the maximum number of digits plus a sign, a period, the letter 'e', another sign and three digits for the exponent
size_t const oldsize = str.size();
str.append(reserve, (char)0);
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...)
size_t added = sp_svg_number_write_de(begin_of_num, reserve, v, precision, minexp);
str.resize(oldsize+added); // remove any trailing characters
}
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 :
|
