src/vspace.C

   1 // -*- C++ -*-
   2 /* This file is part of
   3  * ======================================================
   4  *
   5  *           LyX, The Document Processor
   6  *
   7  *           Copyright 1995 Matthias Ettrich
   8  *           Copyright 1995-2000 The LyX Team.
   9  *
  10  * ====================================================== */
  11
  12 #include <config.h>
  13
  14 #ifdef __GNUG__
  15 #pragma implementation "vspace.h"
  16 #endif
  17
  18 #include "lyx_main.h"
  19 #include "buffer.h"
  20 #include "vspace.h"
  21 #include "lyxrc.h"
  22 #include "lyxtext.h"
  23 #include "BufferView.h"
  24 #include "support/lstrings.h"
  25
  26
  27 /*  length units
  28  */
  29
  30 static const int num_units = LyXLength::UNIT_NONE;
  31
  32 // I am not sure if "mu" should be possible to select (Lgb)
  33 static char const * unit_name[num_units] = { "sp", "pt", "bp", "dd",
  34                                              "mm", "pc", "cc", "cm",
  35                                              "in", "ex", "em", "mu" };
  36
  37
  38 LyXLength::UNIT unitFromString (string const & data)
  39 {
  40         int i = 0;
  41         while ((i < num_units) && (data != unit_name[i])) ++i;
  42         return static_cast<LyXLength::UNIT>(i);
  43 }
  44
  45 /*  The following static items form a simple scanner for
  46  *  length strings, used by isValid[Glue]Length.  See comments there.
  47  */
  48 static float           number[4] = { 0, 0, 0, 0 };
  49 static LyXLength::UNIT unit[4]   = { LyXLength::UNIT_NONE,
  50                                      LyXLength::UNIT_NONE,
  51                                      LyXLength::UNIT_NONE,
  52                                      LyXLength::UNIT_NONE };
  53 //static int number_index, unit_index;
  54 int number_index, unit_index;
  55
  56
  57 static inline
  58 void lyx_advance (string & data, unsigned int n)
  59 {
  60         data.erase(0, n);
  61 }
  62
  63
  64 static inline
  65 bool isEndOfData (string const & data)
  66 {
  67         return frontStrip (data).empty();
  68 }
  69
  70
  71 static
  72 char nextToken (string & data)
  73 {
  74         data = frontStrip(data);
  75         if (data.empty())
  76                 return '\0';
  77         else if (data[0] == '+') {
  78                 lyx_advance (data, 1);
  79                 return '+';
  80         }
  81         else if (prefixIs(data, "plus")) {
  82                 lyx_advance (data, 4);
  83                 return '+';
  84         }
  85         else if (data[0] == '-') {
  86                 lyx_advance (data, 1);
  87                 return '-';
  88         }
  89         else if (prefixIs(data, "minus")) {
  90                 lyx_advance (data, 5);
  91                 return '-';
  92         }
  93         else {
  94                 string::size_type i;
  95
  96                 // I really mean assignment ("=") below, not equality!
  97                 if ((i = data.find_last_of("0123456789.")) != string::npos) {
  98                         if (number_index > 3) return 'E';  // Error
  99                         string buffer = data.substr(0, i + 1).c_str();
 100                         double x = strToDbl(buffer);
 101                         if (x || (buffer[0] == '0')) {
 102                                 number[number_index] = x;
 103                                 lyx_advance (data, i + 1);
 104                                 ++number_index;
 105                                 return 'n';
 106                         } else
 107                                 return 'E';  // Error
 108                 } else if ((i = data.find_last_of("abcdefghijklmnopqrstuvwxyz"))
 109                            != string::npos) {
 110                         if (unit_index > 3) return 'E';  // Error
 111                         string buffer = data.substr(0, i + 1);
 112                         unit[unit_index] = unitFromString (buffer);
 113                         if (unit[unit_index] != LyXLength::UNIT_NONE) {
 114                                 lyx_advance (data, i + 1);
 115                                 ++unit_index;
 116                                 return 'u';
 117                         } else
 118                                 return 'E';  // Error
 119                 } else
 120                         return 'E';  // Error
 121         }
 122 }
 123
 124
 125 struct LaTeXLength {
 126         char const * pattern;
 127         int   plus_val_index, minus_val_index,
 128                 plus_uni_index, minus_uni_index;
 129 };
 130
 131
 132 static
 133 LaTeXLength table[] = {
 134         { "nu",       0, 0, 0, 0 },
 135         { "nu+nu",    2, 0, 2, 0 },
 136         { "nu+nu-nu", 2, 3, 2, 3 },
 137         { "nu+-nu",   2, 2, 2, 2 },
 138         { "nu-nu",    0, 2, 0, 2 },
 139         { "nu-nu+nu", 3, 2, 3, 2 },
 140         { "nu-+nu",   2, 2, 2, 2 },
 141         { "n+nu",     2, 0, 1, 0 },
 142         { "n+n-nu",   2, 3, 1, 1 },
 143         { "n+-nu",    2, 2, 1, 1 },
 144         { "n-nu",     0, 2, 0, 1 },
 145         { "n-n+nu",   3, 2, 1, 1 },
 146         { "n-+nu",    2, 2, 1, 1 },
 147         { "",         0, 0, 0, 0 }   // sentinel, must be empty
 148 };
 149
 150
 151 bool isValidGlueLength (string const & data, LyXGlueLength * result)
 152 {
 153         // This parser is table-driven.  First, it constructs a "pattern"
 154         // that describes the sequence of tokens in "data".  For example,
 155         // "n-nu" means: number, minus sign, number, unit.  As we go along,
 156         // numbers and units are stored into static arrays.  Then, "pattern"
 157         // is searched in the "table".  If it is found, the associated
 158         // table entries tell us which number and unit should go where
 159         // in the LyXLength structure.  Example: if "data" has the "pattern"
 160         // "nu+nu-nu", the associated table entries are "2, 3, 2, 3".
 161         // That means, "plus_val" is the second number that was seen
 162         // in the input, "minus_val" is the third number, and "plus_uni"
 163         // and "minus_uni" are the second and third units, respectively.
 164         // ("val" and "uni" are always the first items seen in "data".)
 165         //     This is the most elegant solution I could find -- a straight-
 166         // forward approach leads to very long, tedious code that would be
 167         // much harder to understand and maintain. (AS)
 168
 169         if (data.empty())
 170                 return true;
 171         string buffer = frontStrip(data);
 172
 173         // To make isValidGlueLength recognize negative values as
 174         // the first number this little hack is needed:
 175         short val_sign = 1; // positive as default
 176         switch(buffer[0]) {
 177         case '-':
 178                 lyx_advance(buffer, 1);
 179                 val_sign = -1;
 180                 break;
 181         case '+':
 182                 lyx_advance(buffer, 1);
 183                 // fall through
 184         default:
 185                 // no action
 186                 break;
 187         }
 188         // end of hack
 189
 190         int       pattern_index = 0, table_index = 0;
 191         char      pattern[20];
 192
 193         number_index = unit_index = 1;  // entries at index 0 are sentinels
 194
 195         // construct "pattern" from "data"
 196         while (!isEndOfData (buffer)) {
 197                 if (pattern_index > 20) return false;
 198                 pattern[pattern_index] = nextToken (buffer);
 199                 if (pattern[pattern_index] == 'E') return false;
 200                 ++pattern_index;
 201         }
 202         pattern[pattern_index] = '\0';
 203
 204         // search "pattern" in "table"
 205         table_index = 0;
 206         while (compare(pattern, table[table_index].pattern)) {
 207                 ++table_index;
 208                 if (!*table[table_index].pattern) return false;
 209         }
 210
 211         // Get the values from the appropriate places.  If an index
 212         // is zero, the corresponding array value is zero or UNIT_NONE,
 213         // so we needn't check this.
 214         if (result) {
 215                 result->val = number[1] * val_sign;
 216                 result->uni = unit[1];
 217                 result->plus_val  = number[table[table_index].plus_val_index];
 218                 result->minus_val = number[table[table_index].minus_val_index];
 219                 result->plus_uni  = unit  [table[table_index].plus_uni_index];
 220                 result->minus_uni = unit  [table[table_index].minus_uni_index];
 221         }
 222         return true;
 223 }
 224
 225
 226 bool isValidLength(string const & data, LyXLength * result)
 227 {
 228         /// This is a trimmed down version of isValidGlueLength.
 229         /// The parser may seem overkill for lengths without
 230         /// glue, but since we already have it, using it is
 231         /// easier than writing something from scratch.
 232
 233         string   buffer = data;
 234         int       pattern_index = 0;
 235         char      pattern[3];
 236
 237         // To make isValidLength recognize negative values
 238         // this little hack is needed:
 239         short val_sign = 1; // positive as default
 240         switch(buffer[0]) {
 241         case '-':
 242                 lyx_advance(buffer, 1);
 243                 val_sign = -1;
 244                 break;
 245         case '+':
 246                 lyx_advance(buffer, 1);
 247                 // fall through
 248         default:
 249                 // no action
 250                 break;
 251         }
 252         // end of hack
 253
 254         number_index = unit_index = 1;  // entries at index 0 are sentinels
 255
 256         // construct "pattern" from "data"
 257         while (!isEndOfData (buffer)) {
 258                 if (pattern_index > 2) return false;
 259                 pattern[pattern_index] = nextToken (buffer);
 260                 if (pattern[pattern_index] == 'E') return false;
 261                 ++pattern_index;
 262         }
 263         pattern[pattern_index] = '\0';
 264
 265         // only the most basic pattern is accepted here
 266         if (compare(pattern, "nu") != 0) return false;
 267
 268         // It _was_ a correct length string.
 269         // Store away the values we found.
 270         if (result) {
 271                 result->val = number[1] * val_sign;
 272                 result->uni = unit[1];
 273         }
 274         return true;
 275 }
 276
 277
 278 /// LyXLength class
 279
 280 LyXLength::LyXLength(string const & data)
 281 {
 282         LyXLength tmp;
 283
 284         if (!isValidLength (data, &tmp))
 285                 return; // should raise an exception
 286         else {
 287                 val = tmp.val;
 288                 uni = tmp.uni;
 289         }
 290 }
 291
 292
 293 string LyXLength::asString() const
 294 {
 295 #ifdef HAVE_SSTREAM
 296         std::ostringstream buffer;
 297         buffer << val << unit_name[uni]; // setw?
 298         return buffer.str().c_str();
 299 #else
 300         char tbuf[20];
 301         ostrstream buffer(tbuf, 20);
 302         buffer << val << unit_name[uni] << '\0'; // setw?
 303         return buffer.str();
 304 #endif
 305 }
 306
 307
 308 /*  LyXGlueLength class
 309  */
 310
 311 LyXGlueLength::LyXGlueLength (string const & data)
 312 {
 313         LyXGlueLength tmp(0.0, PT);
 314
 315         if (!isValidGlueLength (data, &tmp))
 316                 return; // should raise an exception
 317         else {
 318                 val = tmp.val;
 319                 uni = tmp.uni;
 320                 plus_val = tmp.plus_val;
 321                 plus_uni = tmp.plus_uni;
 322                 minus_val = tmp.minus_val;
 323                 minus_uni = tmp.minus_uni;
 324         }
 325 }
 326
 327
 328 string LyXGlueLength::asString() const
 329 {
 330 #ifdef HAVE_SSTREAM
 331         std::ostringstream buffer;
 332 #else
 333         char tbuf[20];
 334         ostrstream buffer(tbuf, 20);
 335 #endif
 336         if (plus_val != 0.0)
 337                 if (minus_val != 0.0)
 338                         if ((uni == plus_uni) && (uni == minus_uni))
 339                                 if (plus_val == minus_val)
 340                                         buffer << val << "+-"
 341                                                << plus_val << unit_name[uni];
 342                                 else
 343                                         buffer << val
 344                                                << '+' << plus_val
 345                                                << '-' << minus_val
 346                                                << unit_name[uni];
 347                         else
 348                                 if (plus_uni == minus_uni
 349                                     && plus_val == minus_val)
 350                                         buffer << val << unit_name[uni]
 351                                                << "+-" << plus_val
 352                                                << unit_name[plus_uni];
 353
 354                                 else
 355                                         buffer << val << unit_name[uni]
 356                                                << '+' << plus_val
 357                                                << unit_name[plus_uni]
 358                                                << '-' << minus_val
 359                                                << unit_name[minus_uni];
 360                 else
 361                         if (uni == plus_uni)
 362                                 buffer << val << '+' << plus_val
 363                                        << unit_name[uni];
 364                         else
 365                                 buffer << val << unit_name[uni]
 366                                        << '+' << plus_val
 367                                        << unit_name[plus_uni];
 368
 369         else
 370                 if (minus_val != 0.0)
 371                         if (uni == minus_uni)
 372                                 buffer << val << '-' << minus_val
 373                                        << unit_name[uni];
 374
 375                         else
 376                                 buffer << val << unit_name[uni]
 377                                        << '-' << minus_val
 378                                        << unit_name[minus_uni];
 379                 else
 380                         buffer << val << unit_name[uni];
 381 #ifdef HAVE_SSTREAM
 382         return buffer.str().c_str();
 383 #else
 384         buffer << '\0';
 385         return buffer.str();
 386 #endif
 387 }
 388
 389
 390 string LyXGlueLength::asLatexString() const
 391 {
 392 #ifdef HAVE_SSTREAM
 393         std::ostringstream buffer;
 394 #else
 395         char tbuf[40];
 396         ostrstream buffer(tbuf, 40);
 397 #endif
 398
 399         if (plus_val != 0.0)
 400                 if (minus_val != 0.0)
 401                         buffer << val << unit_name[uni]
 402                                << " plus "
 403                                << plus_val << unit_name[plus_uni]
 404                                << " minus "
 405                                << minus_val << unit_name[minus_uni];
 406                 else
 407                         buffer << val << unit_name[uni]
 408                                << " plus "
 409                                << plus_val << unit_name[plus_uni];
 410         else
 411                 if (minus_val != 0.0)
 412                         buffer << val << unit_name[uni]
 413                                << " minus "
 414                                << minus_val << unit_name[minus_uni];
 415                 else
 416                         buffer << val << unit_name[uni];
 417 #ifdef HAVE_SSTREAM
 418         return buffer.str().c_str();
 419 #else
 420         buffer << '\0';
 421         return buffer.str();
 422 #endif
 423 }
 424
 425
 426 /*  VSpace class
 427  */
 428
 429 VSpace::VSpace (string const & data)
 430         : kin (NONE), len (0.0, LyXLength::PT)
 431 {
 432         kp = false;
 433         if (data.empty())
 434                 return;
 435         float   value;
 436         string input  = strip(data);
 437
 438         int length = input.length();
 439
 440         if (length > 1 && input[length-1] == '*') {
 441                 kp = true;
 442                 input.erase(length - 1);
 443         }
 444
 445         if      (prefixIs (input, "defskip"))   kin = DEFSKIP;
 446         else if (prefixIs (input, "smallskip")) kin = SMALLSKIP;
 447         else if (prefixIs (input, "medskip"))   kin = MEDSKIP;
 448         else if (prefixIs (input, "bigskip"))   kin = BIGSKIP;
 449         else if (prefixIs (input, "vfill"))     kin = VFILL;
 450         else if (isValidGlueLength (input, &len))
 451                 kin = LENGTH;
 452         else if (sscanf (input.c_str(), "%f", &value) == 1) {
 453                 // This last one is for reading old .lyx files
 454                 // without units in added_space_top/bottom.
 455                 // Let unit default to centimeters here.
 456                 kin = LENGTH;
 457                 len = LyXGlueLength (value, LyXLength::CM);
 458         }
 459 }
 460
 461
 462 bool VSpace::operator==(VSpace const & other) const
 463 {
 464         if (this->kin == other.kin)
 465                 if (this->kin == LENGTH)
 466                         if (this->len == other.len)
 467                                 return this->kp == other.kp;
 468                         else
 469                                 return false;
 470                 else
 471                         return this->kp == other.kp;
 472         else
 473                 return false;
 474 }
 475
 476
 477 string VSpace::asLyXCommand() const
 478 {
 479         string result;
 480
 481         switch (kin) {
 482         case NONE:      break;
 483         case DEFSKIP:   result = "defskip";      break;
 484         case SMALLSKIP: result = "smallskip";    break;
 485         case MEDSKIP:   result = "medskip";      break;
 486         case BIGSKIP:   result = "bigskip";      break;
 487         case VFILL:     result = "vfill";        break;
 488         case LENGTH:    result = len.asString(); break;
 489         }
 490         if (kp && (kin != NONE) && (kin != DEFSKIP))
 491                 return result += '*';
 492         else
 493                 return result;
 494 }
 495
 496
 497 string VSpace::asLatexCommand(BufferParams const & params) const
 498 {
 499         switch (kin) {
 500         case NONE:      return string();
 501         case DEFSKIP:
 502                 return params.getDefSkip().asLatexCommand(params);
 503         case SMALLSKIP: return kp ? "\\vspace*{\\smallskipamount}"
 504                                 : "\\smallskip{}";
 505         case MEDSKIP:   return kp ? "\\vspace*{\\medskipamount}"
 506                                 : "\\medskip{}";
 507         case BIGSKIP:   return kp ? "\\vspace*{\\bigskipamount}"
 508                                 : "\\bigskip{}";
 509         case VFILL:     return kp ? "\\vspace*{\\fill}"
 510                                 : "\\vfill{}";
 511         case LENGTH:    return kp ? "\\vspace*{" + len.asLatexString() + '}'
 512                                 : "\\vspace{" + len.asLatexString() + '}';
 513         }
 514         return string();  // should never be reached
 515 }
 516
 517
 518 int VSpace::inPixels(BufferView * bv) const
 519 {
 520         // Height of a normal line in pixels (zoom factor considered)
 521         int height = bv->text->DefaultHeight(); // [pixels]
 522         int skip = 0;
 523         if (kin == DEFSKIP)
 524             skip = bv->buffer()->params.getDefSkip().inPixels(bv);
 525
 526         return inPixels(height, skip);
 527 }
 528
 529 int VSpace::inPixels(int default_height, int default_skip) const
 530 {
 531         // Height of a normal line in pixels (zoom factor considered)
 532         int height = default_height; // [pixels]
 533
 534         // Zoom factor specified by user in percent
 535         float const zoom = lyxrc.zoom / 100.0; // [percent]
 536
 537         // DPI setting for monitor: pixels/inch
 538         float const dpi = lyxrc.dpi; // screen resolution [pixels/inch]
 539
 540         // We want the result in pixels
 541         float result, value;
 542
 543         switch (kin) {
 544         case NONE: return 0;
 545
 546         case DEFSKIP:
 547                 return default_skip;
 548
 549                 // This is how the skips are normally defined by
 550                 // LateX.  But there should be some way to change
 551                 // this per document.
 552         case SMALLSKIP: return height / 4;
 553         case MEDSKIP:   return height / 2;
 554         case BIGSKIP:   return height;
 555         case VFILL:     return 3 * height;
 556                 // leave space for the vfill symbol
 557         case LENGTH:
 558                 // Pixel values are scaled so that the ratio
 559                 // between lengths and font sizes on the screen
 560                 // is the same as on paper.
 561
 562                 // we don't care about sign of value, we
 563                 // can't display negative anyway
 564                 result = 0.0;
 565                 value = len.value();
 566                 short val_sign = value < 0.0 ? -1 : 1;
 567
 568                 switch (len.unit()) {
 569                 case LyXLength::SP:
 570                         // Scaled point: sp = 1/65536 pt
 571                         result = zoom * dpi * value
 572                                 / (72.27 * 65536); // 4736286.7
 573                         break;
 574                 case LyXLength::PT:
 575                         // Point: 1 pt = 1/72.27 inch
 576                         result = zoom * dpi * value
 577                                 / 72.27; // 72.27
 578                         break;
 579                 case LyXLength::BP:
 580                         // Big point: 1 bp = 1/72 inch
 581                         result = zoom * dpi * value
 582                                 / 72; // 72
 583                         break;
 584                 case LyXLength::DD:
 585                         // Didot: 1157dd = 1238 pt?
 586                         result = zoom * dpi * value
 587                                 / (72.27 / (0.376 * 2.845)); // 67.559735
 588                         break;
 589                 case LyXLength::MM:
 590                         // Millimeter: 1 mm = 1/25.4 inch
 591                         result = zoom * dpi * value
 592                                 / 25.4; // 25.4
 593                         break;
 594                 case LyXLength::PC:
 595                         // Pica: 1 pc = 12 pt
 596                         result = zoom * dpi * value
 597                                 / (72.27 / 12); // 6.0225
 598                         break;
 599                 case LyXLength::CC:
 600                         // Cicero: 1 cc = 12 dd
 601                         result = zoom * dpi * value
 602                                 / (72.27 / (12 * 0.376 * 2.845)); // 5.6299779
 603                         break;
 604                 case LyXLength::CM:
 605                         // Centimeter: 1 cm = 1/2.54 inch
 606                         result = zoom * dpi * value
 607                                 / 2.54; // 2.54
 608                         break;
 609                 case LyXLength::IN:
 610                         // Inch
 611                         result = zoom * dpi * value;
 612                         break;
 613                 case LyXLength::EX:
 614                         // Ex: The height of an "x"
 615                         result = zoom * value * height / 2; // what to / width?
 616                         break;
 617                 case LyXLength::EM: // what to / width?
 618                         // Em: The width of an "m"
 619                         result = zoom * value * height / 2; // Why 2?
 620                         break;
 621                 case LyXLength::MU: // This is probably only allowed in
 622                         // math mode
 623                         result = zoom * value * height;
 624                         break;
 625                 case LyXLength::UNIT_NONE:
 626                         result = 0;  // this cannot happen
 627                         break;
 628                 }
 629                 return int (result * val_sign + 0.5);
 630         }
 631         return 0; // never reached
 632 }