src/lyxlength.C

   1 /* This file is part of
   2  * ======================================================
   3  *
   4  *           LyX, The Document Processor
   5  *
   6  *           Copyright 1995 Matthias Ettrich
   7  *           Copyright 1995-2001 The LyX Team.
   8  *
   9  * ====================================================== */
  10
  11 #include <config.h>
  12
  13 #ifdef __GNUG__
  14 #pragma implementation
  15 #endif
  16
  17 #include "lyxlength.h"
  18 #include "lengthcommon.h"
  19 #include "lyxrc.h"
  20
  21 #include "support/lstrings.h"
  22
  23 #include "Lsstream.h"
  24
  25 #include <cstdlib>
  26
  27 using std::abs;
  28
  29 LyXLength::LyXLength()
  30         : val_(0), unit_(LyXLength::PT)
  31 {}
  32
  33
  34 LyXLength::LyXLength(double v, LyXLength::UNIT u)
  35         : val_(v), unit_(u)
  36 {}
  37
  38
  39 LyXLength::LyXLength(string const & data)
  40         : val_(0), unit_(LyXLength::PT)
  41 {
  42         LyXLength tmp;
  43
  44         if (!isValidLength(data, &tmp))
  45                 return; // should raise an exception
  46
  47         val_  = tmp.val_;
  48         unit_ = tmp.unit_;
  49 }
  50
  51
  52 string const LyXLength::asString() const
  53 {
  54         ostringstream buffer;
  55         buffer << val_ << unit_name[unit_]; // setw?
  56         return STRCONV(buffer.str());
  57 }
  58
  59
  60 string const LyXLength::asLatexString() const
  61 {
  62         ostringstream buffer;
  63         switch (unit_) {
  64         case PTW:
  65             buffer << abs(static_cast<int>(val_/100)) << "."
  66                    << abs(static_cast<int>(val_)%100) << "\\textwidth";
  67             break;
  68         case PCW:
  69             buffer << abs(static_cast<int>(val_/100)) << "."
  70                    << abs(static_cast<int>(val_)%100) << "\\columnwidth";
  71             break;
  72         case PPW:
  73             buffer << abs(static_cast<int>(val_/100)) << "."
  74                    << abs(static_cast<int>(val_)%100) << "\\paperwidth";
  75             break;
  76         case PLW:
  77             buffer << abs(static_cast<int>(val_/100)) << "."
  78                    << abs(static_cast<int>(val_)%100) << "\\linewidth";
  79             break;
  80         case PPH:
  81             buffer << abs(static_cast<int>(val_/100)) << "."
  82                    << abs(static_cast<int>(val_)%100) << "\\paperheight";
  83             break;
  84         case PTH:
  85             buffer << abs(static_cast<int>(val_/100)) << "."
  86                    << abs(static_cast<int>(val_)%100) << "\\textheight";
  87             break;
  88         default:
  89             buffer << val_ << unit_name[unit_]; // setw?
  90             break;
  91         }
  92         return STRCONV(buffer.str());
  93 }
  94
  95
  96 double LyXLength::value() const
  97 {
  98         return val_;
  99 }
 100
 101
 102 LyXLength::UNIT LyXLength::unit() const
 103 {
 104         return unit_;
 105 }
 106
 107
 108 void LyXLength::value(double v)
 109 {
 110         val_ = v;
 111 }
 112
 113
 114 void LyXLength::unit(LyXLength::UNIT u)
 115 {
 116         unit_ = u;
 117 }
 118
 119
 120 bool LyXLength::zero() const
 121 {
 122         return val_ == 0.0;
 123 }
 124
 125
 126 int LyXLength::inPixels(int text_width, int em_width_base) const
 127 {
 128         // Zoom factor specified by user in percent
 129         double const zoom = lyxrc.zoom / 100.0; // [percent]
 130
 131         // DPI setting for monitor: pixels/inch
 132         double const dpi = lyxrc.dpi; // screen resolution [pixels/inch]
 133
 134         double const em_width = (em_width_base > 0)
 135                 ? em_width_base
 136                 : 10*(dpi/72.27)*zoom;
 137         // A different estimate for em_width is
 138         // font_metrics::width('M', LyXFont(LyXFont::ALL_SANE))
 139         // but this estimate might not be more accurate as the screen font
 140         // is different then the latex font.
 141
 142         // Pixel values are scaled so that the ratio
 143         // between lengths and font sizes on the screen
 144         // is the same as on paper.
 145
 146 #ifdef WITH_WARNINGS
 147 #warning if you don't care than either call this function differently or let it return negative values and call abs() explicitly when needed (Andre')
 148 #endif
 149
 150         double result = 0.0;
 151
 152         switch (unit_) {
 153         case LyXLength::SP:
 154                 // Scaled point: sp = 1/65536 pt
 155                 result = zoom * dpi * val_
 156                         / (72.27 * 65536); // 4736286.7
 157                 break;
 158         case LyXLength::PT:
 159                 // Point: 1 pt = 1/72.27 inch
 160                 result = zoom * dpi * val_
 161                         / 72.27; // 72.27
 162                 break;
 163         case LyXLength::BP:
 164                 // Big point: 1 bp = 1/72 inch
 165                 result = zoom * dpi * val_
 166                         / 72; // 72
 167                 break;
 168         case LyXLength::DD:
 169                 // Didot: 1157dd = 1238 pt?
 170                 result = zoom * dpi * val_
 171                         / (72.27 / (0.376 * 2.845)); // 67.559735
 172                 break;
 173         case LyXLength::MM:
 174                 // Millimeter: 1 mm = 1/25.4 inch
 175                 result = zoom * dpi * val_
 176                         / 25.4; // 25.4
 177                 break;
 178         case LyXLength::PC:
 179                 // Pica: 1 pc = 12 pt
 180                 result = zoom * dpi * val_
 181                         / (72.27 / 12); // 6.0225
 182                 break;
 183         case LyXLength::CC:
 184                 // Cicero: 1 cc = 12 dd
 185                 result = zoom * dpi * val_
 186                         / (72.27 / (12 * 0.376 * 2.845)); // 5.6299779
 187                 break;
 188         case LyXLength::CM:
 189                 // Centimeter: 1 cm = 1/2.54 inch
 190                 result = zoom * dpi * val_
 191                         / 2.54; // 2.54
 192                 break;
 193         case LyXLength::IN:
 194                 // Inch
 195                 result = zoom * dpi * val_;
 196                 break;
 197         case LyXLength::EX:
 198                 // Ex: The height of an "x"
 199                 // 0.4305 is the ration between 1ex and 1em in cmr10
 200                 result = val_ * em_width * 0.4305;
 201                 break;
 202         case LyXLength::EM:
 203                 // Em: The width of an "m"
 204                 result = val_ * em_width;
 205                 break;
 206         case LyXLength::MU:
 207                 // math unit = 1/18em
 208                 result = val_ * em_width / 18;
 209                 break;
 210         case LyXLength::PCW: // Always % of workarea
 211         case LyXLength::PTW:
 212         case LyXLength::PLW:
 213                 result = val_ * text_width / 100;
 214                 break;
 215         case LyXLength::PPW:
 216                 // paperwidth/textwidth is 1.7 for A4 paper with default margins
 217                 result = val_ * text_width * 1.7 / 100;
 218                 break;
 219         case LyXLength::PTH:
 220                 result = val_ * text_width * 1.787 / 100;
 221                 break;
 222         case LyXLength::PPH:
 223                 result = val_ * text_width * 2.2 / 100;
 224                 break;
 225         case LyXLength::UNIT_NONE:
 226                 result = 0;  // this cannot happen
 227                 break;
 228         }
 229         return static_cast<int>(result + ((result >= 0) ? 0.5 : -0.5));
 230 }
 231
 232
 233 int LyXLength::inBP() const
 234 {
 235         // return any LyXLength value as a one with
 236         // the PostScript point, called bp (big points)
 237         double result = 0.0;
 238         switch (unit_) {
 239         case LyXLength::CM:
 240                 // 1bp = 0.2835cm
 241                 result = val_ * 28.346;
 242                 break;
 243         case LyXLength::MM:
 244                 // 1bp = 0.02835mm
 245                 result = val_ * 2.8346;
 246                 break;
 247         case LyXLength::IN:
 248                 // 1pt = 1/72in
 249                 result = val_ * 72.0;
 250                 break;
 251         default:
 252                 // no other than bp possible
 253                 result = val_;
 254                 break;
 255         }
 256         return static_cast<int>(result + 0.5);
 257 }
 258
 259
 260 bool operator==(LyXLength const & l1, LyXLength const & l2)
 261 {
 262         return l1.value() == l2.value() && l1.unit() == l2.unit();
 263 }
 264
 265
 266 bool operator!=(LyXLength const & l1, LyXLength const & l2)
 267 {
 268         return !(l1 == l2);
 269 }