src/lyxlength.C

   1 /**
   2  * \file lyxlength.C
   3  * This file is part of LyX, the document processor.
   4  * Licence details can be found in the file COPYING.
   5  *
   6  * \author Matthias Ettrich
   7  * \author Lars Gullik Bjønnes
   8  * \author Jean-Marc Lasgouttes
   9  * \author Angus Leeming
  10  * \author John Levon
  11  * \author Dekel Tsur
  12  *
  13  * Full author contact details are available in file CREDITS.
  14  */
  15
  16 #include <config.h>
  17
  18 #include "lyxlength.h"
  19 #include "lengthcommon.h"
  20 #include "lyxrc.h"
  21
  22 #include <sstream>
  23 #include <iomanip>
  24
  25
  26 using std::ostringstream;
  27 using std::setprecision;
  28 using std::string;
  29
  30
  31 LyXLength::LyXLength()
  32         : val_(0), unit_(LyXLength::UNIT_NONE)
  33 {}
  34
  35
  36 LyXLength::LyXLength(double v, LyXLength::UNIT u)
  37         : val_(v), unit_(u)
  38 {}
  39
  40
  41 LyXLength::LyXLength(string const & data)
  42         : val_(0), unit_(LyXLength::PT)
  43 {
  44         LyXLength tmp;
  45
  46         if (!isValidLength(data, &tmp))
  47                 return; // should raise an exception
  48
  49         val_  = tmp.val_;
  50         unit_ = tmp.unit_;
  51 }
  52
  53
  54 string const LyXLength::asString() const
  55 {
  56         ostringstream os;
  57         os << val_ << unit_name[unit_]; // setw?
  58         return os.str();
  59 }
  60
  61
  62 string const LyXLength::asLatexString() const
  63 {
  64         ostringstream os;
  65         switch (unit_) {
  66         case PTW:
  67                 os << setprecision(2) << val_/100.0 << "\\textwidth";
  68                 break;
  69         case PCW:
  70                 os << setprecision(2) << val_/100.0 << "\\columnwidth";
  71                 break;
  72         case PPW:
  73                 os << setprecision(2) << val_/100.0 << "\\paperwidth";
  74                 break;
  75         case PLW:
  76                 os << setprecision(2) << val_/100.0 << "\\linewidth";
  77                 break;
  78         case PPH:
  79                 os << setprecision(2) << val_/100.0 << "\\paperheight";
  80                 break;
  81         case PTH:
  82                 os << setprecision(2) << val_/100.0 << "\\textheight";
  83                 break;
  84         default:
  85                 os << setprecision(2) << val_ << unit_name[unit_];
  86           break;
  87         }
  88         return os.str();
  89 }
  90
  91
  92 double LyXLength::value() const
  93 {
  94         return val_;
  95 }
  96
  97
  98 LyXLength::UNIT LyXLength::unit() const
  99 {
 100         return unit_;
 101 }
 102
 103
 104 void LyXLength::value(double v)
 105 {
 106         val_ = v;
 107 }
 108
 109
 110 void LyXLength::unit(LyXLength::UNIT u)
 111 {
 112         unit_ = u;
 113 }
 114
 115
 116 bool LyXLength::zero() const
 117 {
 118         return val_ == 0.0;
 119 }
 120
 121
 122 bool LyXLength::empty() const
 123 {
 124         return unit_ == LyXLength::UNIT_NONE;
 125 }
 126
 127
 128 int LyXLength::inPixels(int text_width, int em_width_base) const
 129 {
 130         // Zoom factor specified by user in percent
 131         double const zoom = lyxrc.zoom / 100.0; // [percent]
 132
 133         // DPI setting for monitor: pixels/inch
 134         double const dpi = lyxrc.dpi; // screen resolution [pixels/inch]
 135
 136         double const em_width = (em_width_base > 0)
 137                 ? em_width_base
 138                 : 10*(dpi/72.27)*zoom;
 139         // A different estimate for em_width is
 140         // font_metrics::width('M', LyXFont(LyXFont::ALL_SANE))
 141         // but this estimate might not be more accurate as the screen font
 142         // is different then the latex font.
 143
 144         // Pixel values are scaled so that the ratio
 145         // between lengths and font sizes on the screen
 146         // is the same as on paper.
 147
 148         double result = 0.0;
 149
 150         switch (unit_) {
 151         case LyXLength::SP:
 152                 // Scaled point: sp = 1/65536 pt
 153                 result = zoom * dpi * val_
 154                         / (72.27 * 65536); // 4736286.7
 155                 break;
 156         case LyXLength::PT:
 157                 // Point: 1 pt = 1/72.27 inch
 158                 result = zoom * dpi * val_
 159                         / 72.27; // 72.27
 160                 break;
 161         case LyXLength::BP:
 162                 // Big point: 1 bp = 1/72 inch
 163                 result = zoom * dpi * val_
 164                         / 72; // 72
 165                 break;
 166         case LyXLength::DD:
 167                 // Didot: 1157dd = 1238 pt?
 168                 result = zoom * dpi * val_
 169                         / (72.27 / (0.376 * 2.845)); // 67.559735
 170                 break;
 171         case LyXLength::MM:
 172                 // Millimeter: 1 mm = 1/25.4 inch
 173                 result = zoom * dpi * val_
 174                         / 25.4; // 25.4
 175                 break;
 176         case LyXLength::PC:
 177                 // Pica: 1 pc = 12 pt
 178                 result = zoom * dpi * val_
 179                         / (72.27 / 12); // 6.0225
 180                 break;
 181         case LyXLength::CC:
 182                 // Cicero: 1 cc = 12 dd
 183                 result = zoom * dpi * val_
 184                         / (72.27 / (12 * 0.376 * 2.845)); // 5.6299779
 185                 break;
 186         case LyXLength::CM:
 187                 // Centimeter: 1 cm = 1/2.54 inch
 188                 result = zoom * dpi * val_
 189                         / 2.54; // 2.54
 190                 break;
 191         case LyXLength::IN:
 192                 // Inch
 193                 result = zoom * dpi * val_;
 194                 break;
 195         case LyXLength::EX:
 196                 // Ex: The height of an "x"
 197                 // 0.4305 is the ration between 1ex and 1em in cmr10
 198                 result = val_ * em_width * 0.4305;
 199                 break;
 200         case LyXLength::EM:
 201                 // Em: The width of an "m"
 202                 result = val_ * em_width;
 203                 break;
 204         case LyXLength::MU:
 205                 // math unit = 1/18em
 206                 result = val_ * em_width / 18;
 207                 break;
 208         case LyXLength::PCW: // Always % of workarea
 209         case LyXLength::PTW:
 210         case LyXLength::PLW:
 211                 result = val_ * text_width / 100;
 212                 break;
 213         case LyXLength::PPW:
 214                 // paperwidth/textwidth is 1.7 for A4 paper with default margins
 215                 result = val_ * text_width * 1.7 / 100;
 216                 break;
 217         case LyXLength::PTH:
 218                 result = val_ * text_width * 1.787 / 100;
 219                 break;
 220         case LyXLength::PPH:
 221                 result = val_ * text_width * 2.2 / 100;
 222                 break;
 223         case LyXLength::UNIT_NONE:
 224                 result = 0;  // this cannot happen
 225                 break;
 226         }
 227         return static_cast<int>(result + ((result >= 0) ? 0.5 : -0.5));
 228 }
 229
 230
 231 int LyXLength::inBP() const
 232 {
 233         // return any LyXLength value as a one with
 234         // the PostScript point, called bp (big points)
 235         double result = 0.0;
 236         switch (unit_) {
 237         case LyXLength::CM:
 238                 // 1bp = 0.2835cm
 239                 result = val_ * 28.346;
 240                 break;
 241         case LyXLength::MM:
 242                 // 1bp = 0.02835mm
 243                 result = val_ * 2.8346;
 244                 break;
 245         case LyXLength::IN:
 246                 // 1pt = 1/72in
 247                 result = val_ * 72.0;
 248                 break;
 249         default:
 250                 // no other than bp possible
 251                 result = val_;
 252                 break;
 253         }
 254         return static_cast<int>(result + 0.5);
 255 }
 256
 257
 258 bool operator==(LyXLength const & l1, LyXLength const & l2)
 259 {
 260         return l1.value() == l2.value() && l1.unit() == l2.unit();
 261 }
 262
 263
 264 bool operator!=(LyXLength const & l1, LyXLength const & l2)
 265 {
 266         return !(l1 == l2);
 267 }