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