src/vspace.C

   1 // -*- C++ -*-
   2 /* This file is part of
   3  * ======================================================
   4  *
   5  *           LyX, The Document Processor
   6  *
   7  *          Copyright (C) 1995 Matthias Ettrich
   8  *          Copyright (C) 1995-1998 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 <stdio.h>
  24 #include <string.h>
  25 #include "BufferView.h"
  26
  27 extern LyXRC * lyxrc;
  28 extern BufferView *current_view;
  29
  30 //      $Id: vspace.C,v 1.1 1999/09/27 18:44:38 larsbj Exp $
  31
  32 #if !defined(lint) && !defined(WITH_WARNINGS)
  33 static char vcid[] = "$Id: vspace.C,v 1.1 1999/09/27 18:44:38 larsbj Exp $";
  34 #endif /* lint */
  35
  36 /*  length units
  37  */
  38
  39 static const int   num_units            = int(LyXLength::UNIT_NONE);
  40
  41 // I am not sure if "mu" should be possible to select (Lgb)
  42 static char const* unit_name[num_units] = { "sp", "pt", "bp", "dd",
  43                                             "mm", "pc", "cc", "cm",
  44                                             "in", "ex", "em", "mu" };
  45
  46
  47 LyXLength::UNIT unitFromString (LString const & data)
  48 {
  49         int i=0;
  50         while ((i<num_units) && (data != unit_name[i])) i++;
  51         return (LyXLength::UNIT)i;
  52 }
  53
  54 /*  The following static items form a simple scanner for
  55  *  length strings, used by isValid[Glue]Length.  See comments there.
  56  */
  57 static float           number[4] = { 0, 0, 0, 0 };
  58 static LyXLength::UNIT unit[4]   = { LyXLength::UNIT_NONE,
  59                                      LyXLength::UNIT_NONE,
  60                                      LyXLength::UNIT_NONE,
  61                                      LyXLength::UNIT_NONE };
  62 //static int number_index, unit_index;
  63 int number_index, unit_index;
  64
  65 static void advance (LString& data, const int n)
  66 {
  67         if (data.length() <= n)
  68                 data.clean();
  69         else
  70                 data.substring (n, data.length()-1);
  71 }
  72
  73 static bool isEndOfData (LString& data)
  74 {
  75         data.frontStrip (' ');
  76         return data.empty();
  77 }
  78
  79 static char nextToken (LString& data)
  80 {
  81         data.frontStrip (' ');
  82
  83         if (data.empty())
  84                 return '\0';
  85         else if (data[0] == '+') {
  86                 advance (data, 1);
  87                 return '+';
  88         }
  89         else if (data.prefixIs ("plus")) {
  90                 advance (data, 4);
  91                 return '+';
  92         }
  93         else if (data[0] == '-') {
  94                 advance (data, 1);
  95                 return '-';
  96         }
  97         else if (data.prefixIs ("minus")) {
  98                 advance (data, 5);
  99                 return '-';
 100         }
 101         else {
 102                 int      i;
 103
 104                 // I really mean assignment ("=") below, not equality!
 105
 106                 if ((i = strspn (data.c_str(), "0123456789."))) {
 107                         if (number_index > 3) return 'E';  // Error
 108                         LString buffer = data;
 109                         buffer.substring (0, i-1);
 110                         if (sscanf (buffer.c_str(),
 111                                     "%f", &number[number_index]) == 1) {
 112                                 advance (data, i);
 113                                 number_index++;
 114                                 return 'n';
 115                         } else
 116                                 return 'E';  // Error
 117                 } else if ((i = strspn (data.c_str(),
 118                                        "abcdefghijklmnopqrstuvwxyz"))) {
 119                         if (unit_index > 3) return 'E';  // Error
 120                         LString buffer = data; buffer.substring (0, i-1);
 121                         unit[unit_index] = unitFromString (buffer);
 122                         if (unit[unit_index] != LyXLength::UNIT_NONE) {
 123                                 advance (data, i);
 124                                 unit_index++;
 125                                 return 'u';
 126                         } else
 127                                 return 'E';  // Error
 128                 } else
 129                         return 'E';  // Error
 130         }
 131 }
 132
 133 static struct {
 134         char const* pattern;
 135         int   plus_val_index, minus_val_index,
 136               plus_uni_index, minus_uni_index;
 137 } table[] = { { "nu",       0, 0, 0, 0 },
 138               { "nu+nu",    2, 0, 2, 0 },
 139               { "nu+nu-nu", 2, 3, 2, 3 },
 140               { "nu+-nu",   2, 2, 2, 2 },
 141               { "nu-nu",    0, 2, 0, 2 },
 142               { "nu-nu+nu", 3, 2, 3, 2 },
 143               { "nu-+nu",   2, 2, 2, 2 },
 144               { "n+nu",     2, 0, 1, 0 },
 145               { "n+n-nu",   2, 3, 1, 1 },
 146               { "n+-nu",    2, 2, 1, 1 },
 147               { "n-nu",     0, 2, 0, 1 },
 148               { "n-n+nu",   3, 2, 1, 1 },
 149               { "n-+nu",    2, 2, 1, 1 },
 150               { "",         0, 0, 0, 0 }   // sentinel, must be empty
 151 };
 152
 153 bool isValidGlueLength (LString const & data, LyXGlueLength* result)
 154 {
 155         // This parser is table-driven.  First, it constructs a "pattern"
 156         // that describes the sequence of tokens in "data".  For example,
 157         // "n-nu" means: number, minus sign, number, unit.  As we go along,
 158         // numbers and units are stored into static arrays.  Then, "pattern"
 159         // is searched in the "table".  If it is found, the associated
 160         // table entries tell us which number and unit should go where
 161         // in the LyXLength structure.  Example: if "data" has the "pattern"
 162         // "nu+nu-nu", the associated table entries are "2, 3, 2, 3".
 163         // That means, "plus_val" is the second number that was seen
 164         // in the input, "minus_val" is the third number, and "plus_uni"
 165         // and "minus_uni" are the second and third units, respectively.
 166         // ("val" and "uni" are always the first items seen in "data".)
 167         //     This is the most elegant solution I could find -- a straight-
 168         // forward approach leads to very long, tedious code that would be
 169         // much harder to understand and maintain. (AS)
 170
 171         LString   buffer = data;
 172         buffer.frontStrip(' ');
 173
 174         // To make isValidGlueLength recognize negative values as
 175         // the first number this little hack is needed:
 176         short val_sign = 1; // positive as default
 177         switch(buffer[0]) {
 178         case '-':
 179                 advance(buffer, 1);
 180                 val_sign = -1;
 181                 break;
 182         case '+':
 183                 advance(buffer, 1);
 184                 // fall through
 185         default:
 186                 // no action
 187                 break;
 188         }
 189         // end of hack
 190
 191         int       pattern_index = 0, table_index = 0;
 192         char      pattern[20];
 193
 194         number_index = unit_index = 1;  // entries at index 0 are sentinels
 195
 196         // construct "pattern" from "data"
 197         while (!isEndOfData (buffer)) {
 198                 if (pattern_index > 20) return false;
 199                 pattern[pattern_index] = nextToken (buffer);
 200                 if (pattern[pattern_index] == 'E') return false;
 201                 pattern_index++;
 202         }
 203         pattern[pattern_index] = '\0';
 204
 205         // search "pattern" in "table"
 206         table_index = 0;
 207         while (strcmp (pattern, table[table_index].pattern)) {
 208                 table_index++;
 209                 if (!*table[table_index].pattern) return false;
 210         }
 211
 212         // Get the values from the appropriate places.  If an index
 213         // is zero, the corresponding array value is zero or UNIT_NONE,
 214         // so we needn't check this.
 215         if (result) {
 216             result->val = number[1] * val_sign;
 217             result->uni = unit[1];
 218             result->plus_val  = number[table[table_index].plus_val_index];
 219             result->minus_val = number[table[table_index].minus_val_index];
 220             result->plus_uni  = unit  [table[table_index].plus_uni_index];
 221             result->minus_uni = unit  [table[table_index].minus_uni_index];
 222         }
 223         return true;
 224 }
 225
 226
 227 bool isValidLength(LString const & data, LyXLength* result)
 228 {
 229         /// This is a trimmed down version of isValidGlueLength.
 230         /// The parser may seem overkill for lengths without
 231         /// glue, but since we already have it, using it is
 232         /// easier than writing something from scratch.
 233
 234         LString   buffer = data;
 235         int       pattern_index = 0;
 236         char      pattern[3];
 237
 238         // To make isValidLength recognize negative values
 239         // this little hack is needed:
 240         short val_sign = 1; // positive as default
 241         switch(buffer[0]) {
 242         case '-':
 243                 advance(buffer, 1);
 244                 val_sign = -1;
 245                 break;
 246         case '+':
 247                 advance(buffer, 1);
 248                 // fall through
 249         default:
 250                 // no action
 251                 break;
 252         }
 253         // end of hack
 254
 255         number_index = unit_index = 1;  // entries at index 0 are sentinels
 256
 257         // construct "pattern" from "data"
 258         while (!isEndOfData (buffer)) {
 259                 if (pattern_index > 2) return false;
 260                 pattern[pattern_index] = nextToken (buffer);
 261                 if (pattern[pattern_index] == 'E') return false;
 262                 pattern_index++;
 263         }
 264         pattern[pattern_index] = '\0';
 265
 266         // only the most basic pattern is accepted here
 267         if (strcmp (pattern, "nu") != 0) return false;
 268
 269         // It _was_ a correct length string.
 270         // Store away the values we found.
 271         if (result) {
 272             result->val = number[1]*val_sign;
 273             result->uni = unit[1];
 274         }
 275         return true;
 276 }
 277
 278 /// LyXLength class
 279
 280 LyXLength::LyXLength(LString 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 bool LyXLength::operator== (LyXLength other)
 293 {
 294         return (this->val == other.val)
 295             && (this->uni == other.uni);
 296 }
 297
 298 LString LyXLength::asString() const
 299 {
 300         char buffer[20];
 301
 302         sprintf (buffer, "%g%s", val, unit_name[uni]);
 303         return LString (buffer);
 304 }
 305
 306
 307 /*  LyXGlueLength class
 308  */
 309
 310 LyXGlueLength::LyXGlueLength (LString const & data)
 311 {
 312         LyXGlueLength tmp(0.0, PT);
 313
 314         if (!isValidGlueLength (data, &tmp))
 315                 return; // should raise an exception
 316         else {
 317                 val=tmp.val;
 318                 uni=tmp.uni;
 319                 plus_val =tmp.plus_val;
 320                 plus_uni =tmp.plus_uni;
 321                 minus_val=tmp.minus_val;
 322                 minus_uni=tmp.minus_uni;
 323         }
 324 }
 325
 326
 327 bool LyXGlueLength::operator== (LyXGlueLength other)
 328 {
 329         return (this->val == other.val)
 330             && (this->uni == other.uni)
 331             && (this->plus_val  == other.plus_val)
 332             && (this->plus_uni  == other.plus_uni)
 333             && (this->minus_val == other.minus_val)
 334             && (this->minus_uni == other.minus_uni);
 335 }
 336
 337
 338 LString LyXGlueLength::asString () const
 339 {
 340         char buffer[20];
 341
 342         if (plus_val != 0.0)
 343             if (minus_val != 0.0)
 344                 if ((uni == plus_uni) && (uni == minus_uni))
 345                     if (plus_val == minus_val)
 346                         sprintf (buffer, "%g+-%g%s",
 347                                  val, plus_val, unit_name[uni]);
 348                     else
 349                         sprintf (buffer, "%g+%g-%g%s",
 350                                  val, plus_val, minus_val,
 351                                  unit_name[uni]);
 352                 else
 353                     if ((plus_uni == minus_uni) && (plus_val == minus_val))
 354                         sprintf (buffer, "%g%s+-%g%s",
 355                                  val, unit_name[uni],
 356                                  plus_val, unit_name[plus_uni]);
 357                     else
 358                         sprintf (buffer, "%g%s+%g%s-%g%s",
 359                                  val,       unit_name[uni],
 360                                  plus_val,  unit_name[plus_uni],
 361                                  minus_val, unit_name[minus_uni]);
 362             else
 363                 if (uni == plus_uni)
 364                     sprintf (buffer, "%g+%g%s",
 365                              val, plus_val, unit_name[uni]);
 366                 else
 367                     sprintf (buffer, "%g%s+%g%s",
 368                              val,      unit_name[uni],
 369                              plus_val, unit_name[plus_uni]);
 370         else
 371             if (minus_val != 0.0)
 372                 if (uni == minus_uni)
 373                     sprintf (buffer, "%g-%g%s",
 374                              val, minus_val, unit_name[uni]);
 375                 else
 376                     sprintf (buffer, "%g%s-%g%s",
 377                              val,       unit_name[uni],
 378                              minus_val, unit_name[minus_uni]);
 379             else
 380                 sprintf (buffer, "%g%s", val, unit_name[uni]);
 381         return LString (buffer);
 382 }
 383
 384
 385 LString LyXGlueLength::asLatexString() const
 386 {
 387         char buffer[40];
 388
 389         if (plus_val != 0.0)
 390                 if (minus_val != 0.0)
 391                         sprintf (buffer, "%g%s plus %g%s minus %g%s",
 392                                  val, unit_name[uni],
 393                                  plus_val,  unit_name[plus_uni],
 394                                  minus_val, unit_name[minus_uni]);
 395                 else
 396                         sprintf (buffer, "%g%s plus %g%s",
 397                                  val,      unit_name[uni],
 398                                  plus_val, unit_name[plus_uni]);
 399         else
 400                 if (minus_val != 0.0)
 401                         sprintf (buffer, "%g%s minus %g%s",
 402                                  val,       unit_name[uni],
 403                                  minus_val, unit_name[minus_uni]);
 404                 else
 405                         sprintf (buffer, "%g%s",
 406                                  val, unit_name[uni]);
 407         return LString (buffer);
 408 }
 409
 410
 411 /*  VSpace class
 412  */
 413
 414 VSpace::VSpace (LString const & data)
 415         : kin (NONE), len (0.0, LyXLength::PT)
 416 {
 417         float   value;
 418         LString input  = data;
 419
 420         input.strip(' ');
 421         int length = input.length();
 422
 423         if (length > 1 && input[length-1] == '*') {
 424                 kp = true;
 425                 input.substring (0, length-2);
 426         } else
 427                 kp = false;
 428
 429         if      (input.prefixIs ("defskip"))   kin = DEFSKIP;
 430         else if (input.prefixIs ("smallskip")) kin = SMALLSKIP;
 431         else if (input.prefixIs ("medskip"))   kin = MEDSKIP;
 432         else if (input.prefixIs ("bigskip"))   kin = BIGSKIP;
 433         else if (input.prefixIs ("vfill"))     kin = VFILL;
 434         else if (isValidGlueLength (input, &len))
 435                 kin = LENGTH;
 436         else if (sscanf (input.c_str(), "%f", &value) == 1) {
 437                 // This last one is for reading old .lyx files
 438                 // without units in added_space_top/bottom.
 439                 // Let unit default to centimeters here.
 440                 kin = LENGTH;
 441                 len = LyXGlueLength (value, LyXLength::CM);
 442         }
 443 }
 444
 445
 446 bool VSpace::operator== (VSpace other)
 447 {
 448         if (this->kin == other.kin)
 449                 if (this->kin == LENGTH)
 450                         if (this->len == other.len)
 451                                 return this->kp == other.kp;
 452                         else
 453                                 return false;
 454                 else
 455                         return this->kp == other.kp;
 456         else
 457                 return false;
 458 }
 459
 460
 461 LString VSpace::asLyXCommand() const
 462 {
 463         LString result;
 464
 465         switch (kin) {
 466         case NONE:      break;
 467         case DEFSKIP:   result = "defskip";      break;
 468         case SMALLSKIP: result = "smallskip";    break;
 469         case MEDSKIP:   result = "medskip";      break;
 470         case BIGSKIP:   result = "bigskip";      break;
 471         case VFILL:     result = "vfill";        break;
 472         case LENGTH:    result = len.asString(); break;
 473         }
 474         if (kp && (kin != NONE) && (kin != DEFSKIP))
 475                 return result += '*';
 476         else
 477                 return result;
 478 }
 479
 480
 481 LString VSpace::asLatexCommand() const
 482 {
 483         switch (kin) {
 484         case NONE:      return LString();
 485         case DEFSKIP:
 486           return current_view->currentBuffer()->params.getDefSkip().asLatexCommand();
 487         case SMALLSKIP: return kp ? "\\vspace*{\\smallskipamount}"
 488                                   : "\\smallskip{}";
 489         case MEDSKIP:   return kp ? "\\vspace*{\\medskipamount}"
 490                                   : "\\medskip{}";
 491         case BIGSKIP:   return kp ? "\\vspace*{\\bigskipamount}"
 492                                   : "\\bigskip{}";
 493         case VFILL:     return kp ? "\\vspace*{\\fill}"
 494                                   : "\\vfill{}";
 495         case LENGTH:    return kp ? "\\vspace*{" + len.asLatexString() + '}'
 496                                   : "\\vspace{" + len.asLatexString() + '}';
 497         }
 498         return LString();  // should never be reached
 499 }
 500
 501
 502 int VSpace::inPixels() const
 503 {
 504         // Height of a normal line in pixels (zoom factor considered)
 505         int height = current_view->currentBuffer()->text->DefaultHeight(); // [pixels]
 506
 507         // Zoom factor specified by user in percent
 508         float const zoom = lyxrc->zoom / 100.0; // [percent]
 509
 510         // DPI setting for monitor: pixels/inch
 511         float const dpi = lyxrc->dpi; // screen resolution [pixels/inch]
 512
 513         // We want the result in pixels
 514         float result, value;
 515
 516         switch (kin) {
 517         case NONE: return 0;
 518
 519         case DEFSKIP:
 520           return current_view->currentBuffer()->params.getDefSkip().inPixels();
 521
 522         // This is how the skips are normally defined by
 523         // LateX.  But there should be some way to change
 524         // this per document.
 525         case SMALLSKIP: return height/4;
 526         case MEDSKIP:   return height/2;
 527         case BIGSKIP:   return height;
 528         case VFILL:     return 3*height;
 529                         // leave space for the vfill symbol
 530         case LENGTH:
 531                 // Pixel values are scaled so that the ratio
 532                 // between lengths and font sizes on the screen
 533                 // is the same as on paper.
 534
 535                 // we don't care about sign of value, we
 536                 // can't display negative anyway
 537                 result = 0.0;
 538                 value = len.value();
 539                 short val_sign = value < 0.0 ? -1 : 1;
 540
 541                 switch (len.unit()) {
 542                 case LyXLength::SP:
 543                         // Scaled point: sp = 1/65536 pt
 544                         result = zoom * dpi * value
 545                                 / (72.27 * 65536); // 4736286.7
 546                         break;
 547                 case LyXLength::PT:
 548                         // Point: 1 pt = 1/72.27 inch
 549                         result = zoom * dpi * value
 550                                 / 72.27; // 72.27
 551                         break;
 552                 case LyXLength::BP:
 553                         // Big point: 1 bp = 1/72 inch
 554                         result = zoom * dpi * value
 555                                 / 72; // 72
 556                         break;
 557                 case LyXLength::DD:
 558                         // Didot: 1157dd = 1238 pt?
 559                         result = zoom * dpi * value
 560                                 / (72.27/(0.376 * 2.845)); // 67.559735
 561                         break;
 562                 case LyXLength::MM:
 563                         // Millimeter: 1 mm = 1/25.4 inch
 564                         result = zoom * dpi * value
 565                                 / 25.4; // 25.4
 566                         break;
 567                 case LyXLength::PC:
 568                         // Pica: 1 pc = 12 pt
 569                         result = zoom * dpi * value
 570                                 / (72.27/12); // 6.0225
 571                         break;
 572                 case LyXLength::CC:
 573                         // Cicero: 1 cc = 12 dd
 574                         result = zoom * dpi * value
 575                                 / (72.27/ (12*0.376*2.845)); // 5.6299779
 576                         break;
 577                 case LyXLength::CM:
 578                         // Centimeter: 1 cm = 1/2.54 inch
 579                         result = zoom * dpi * value
 580                                 / 2.54; // 2.54
 581                         break;
 582                 case LyXLength::IN:
 583                         // Inch
 584                         result = zoom * dpi * value;
 585                         break;
 586                 case LyXLength::EX:
 587                         // Ex: The height of an "x"
 588                         result = zoom * value * height / 2; // what to / width?
 589                         break;
 590                 case LyXLength::EM: // what to / width?
 591                         // Em: The width of an "m"
 592                         result = zoom * value * height / 2; // Why 2?
 593                         break;
 594                 case LyXLength::MU: // This is probably only allowed in
 595                                     // math mode
 596                         result = zoom * value * height;
 597                         break;
 598                 case LyXLength::UNIT_NONE:
 599                         result = 0;  // this cannot happen
 600                         break;
 601                 }
 602                 return int (result * val_sign + 0.5);
 603         }
 604         return 0; // never reached
 605 }