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