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