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