dlls/riched20/run.c

   1 /*
   2  * RichEdit - operations on runs (diRun, rectangular pieces of paragraphs).
   3  * Splitting/joining runs. Adjusting offsets after deleting/adding content.
   4  * Character/pixel conversions.
   5  *
   6  * Copyright 2004 by Krzysztof Foltman
   7  * Copyright 2006 by Phil Krylov
   8  *
   9  * This library is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License as published by the Free Software Foundation; either
  12  * version 2.1 of the License, or (at your option) any later version.
  13  *
  14  * This library is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with this library; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  22  */
  23
  24 #include "editor.h"
  25
  26 WINE_DEFAULT_DEBUG_CHANNEL(richedit);
  27 WINE_DECLARE_DEBUG_CHANNEL(richedit_check);
  28 WINE_DECLARE_DEBUG_CHANNEL(richedit_lists);
  29
  30 BOOL cursor_next_run( ME_Cursor *cursor, BOOL all_para )
  31 {
  32     ME_DisplayItem *p = run_get_di( cursor->run )->next;
  33
  34     while (p->type != diTextEnd)
  35     {
  36         if (p->type == diParagraph && !all_para) return FALSE;
  37         else if (p->type == diRun)
  38         {
  39             cursor->run = &p->member.run;
  40             cursor->para = cursor->run->para;
  41             cursor->nOffset = 0;
  42             return TRUE;
  43         }
  44         p = p->next;
  45     }
  46     return FALSE;
  47 }
  48
  49 BOOL cursor_prev_run( ME_Cursor *cursor, BOOL all_para )
  50 {
  51     ME_DisplayItem *p = run_get_di( cursor->run )->prev;
  52
  53     while (p->type != diTextStart)
  54     {
  55         if (p->type == diParagraph && !all_para) return FALSE;
  56         else if (p->type == diRun)
  57         {
  58             cursor->run = &p->member.run;
  59             cursor->para = cursor->run->para;
  60             cursor->nOffset = 0;
  61             return TRUE;
  62         }
  63         p = p->prev;
  64     }
  65     return FALSE;
  66 }
  67
  68 ME_Run *run_next( ME_Run *run )
  69 {
  70     ME_Cursor cursor;
  71
  72     cursor.run = run;
  73     cursor.para = run->para;
  74     cursor.nOffset = 0;
  75
  76     if (cursor_next_run( &cursor, FALSE ))
  77         return cursor.run;
  78
  79     return NULL;
  80 }
  81
  82 ME_Run *run_prev( ME_Run *run )
  83 {
  84     ME_Cursor cursor;
  85
  86     cursor.run = run;
  87     cursor.para = run->para;
  88     cursor.nOffset = 0;
  89
  90     if (cursor_prev_run( &cursor, FALSE ))
  91         return cursor.run;
  92
  93     return NULL;
  94 }
  95
  96 ME_Run *run_next_all_paras( ME_Run *run )
  97 {
  98     ME_Cursor cursor;
  99
 100     cursor.run = run;
 101     cursor.para = run->para;
 102     cursor.nOffset = 0;
 103
 104     if (cursor_next_run( &cursor, TRUE ))
 105         return cursor.run;
 106
 107     return NULL;
 108 }
 109
 110 ME_Run *run_prev_all_paras( ME_Run *run )
 111 {
 112     ME_Cursor cursor;
 113
 114     cursor.run = run;
 115     cursor.para = run->para;
 116     cursor.nOffset = 0;
 117
 118     if (cursor_prev_run( &cursor, TRUE ))
 119         return cursor.run;
 120
 121     return NULL;
 122 }
 123
 124 /******************************************************************************
 125  * ME_CanJoinRuns
 126  *
 127  * Returns TRUE if two runs can be safely merged into one, FALSE otherwise.
 128  */
 129 BOOL ME_CanJoinRuns(const ME_Run *run1, const ME_Run *run2)
 130 {
 131   if ((run1->nFlags | run2->nFlags) & MERF_NOJOIN)
 132     return FALSE;
 133   if (run1->style != run2->style)
 134     return FALSE;
 135   if ((run1->nFlags & MERF_STYLEFLAGS) != (run2->nFlags & MERF_STYLEFLAGS))
 136     return FALSE;
 137   return TRUE;
 138 }
 139
 140 /******************************************************************************
 141  * editor_propagate_char_ofs
 142  *
 143  * Shifts (increases or decreases) character offset (relative to beginning of
 144  * the document) of the part of the text starting from given place.
 145  * Call with only one of para or run non-NULL.
 146  */
 147 void editor_propagate_char_ofs( ME_Paragraph *para, ME_Run *run, int shift )
 148 {
 149     assert( !para ^ !run );
 150
 151     if (run)
 152     {
 153         para = para_next( run->para );
 154         do
 155         {
 156             run->nCharOfs += shift;
 157             run = run_next( run );
 158         } while (run);
 159     }
 160
 161     do
 162     {
 163         para->nCharOfs += shift;
 164         para = para_next( para );
 165     } while (para);
 166 }
 167
 168 /******************************************************************************
 169  * ME_CheckCharOffsets
 170  *
 171  * Checks if editor lists' validity and optionally dumps the document structure
 172  */
 173 void ME_CheckCharOffsets(ME_TextEditor *editor)
 174 {
 175   ME_DisplayItem *p = editor->pBuffer->pFirst;
 176   int ofs = 0, ofsp = 0;
 177
 178   if (!TRACE_ON(richedit_check))
 179     return;
 180
 181   TRACE_(richedit_check)("Checking begin\n");
 182   if(TRACE_ON(richedit_lists))
 183   {
 184     TRACE_(richedit_lists)("---\n");
 185     ME_DumpDocument(editor->pBuffer);
 186   }
 187   do {
 188     p = ME_FindItemFwd(p, diRunOrParagraphOrEnd);
 189     switch(p->type) {
 190       case diTextEnd:
 191         TRACE_(richedit_check)("tend, real ofsp = %d, counted = %d\n", p->member.para.nCharOfs, ofsp+ofs);
 192         assert(ofsp+ofs == p->member.para.nCharOfs);
 193         TRACE_(richedit_check)("Checking finished\n");
 194         return;
 195       case diParagraph:
 196         TRACE_(richedit_check)("para, real ofsp = %d, counted = %d\n", p->member.para.nCharOfs, ofsp+ofs);
 197         assert(ofsp+ofs == p->member.para.nCharOfs);
 198         ofsp = p->member.para.nCharOfs;
 199         ofs = 0;
 200         break;
 201       case diRun:
 202         TRACE_(richedit_check)("run, real ofs = %d (+ofsp = %d), counted = %d, len = %d, txt = %s, flags=%08x, fx&mask = %08x\n",
 203           p->member.run.nCharOfs, p->member.run.nCharOfs+ofsp, ofsp+ofs,
 204           p->member.run.len, debugstr_run( &p->member.run ),
 205           p->member.run.nFlags,
 206           p->member.run.style->fmt.dwMask & p->member.run.style->fmt.dwEffects);
 207         assert(ofs == p->member.run.nCharOfs);
 208         assert(p->member.run.len);
 209         ofs += p->member.run.len;
 210         break;
 211       case diCell:
 212         TRACE_(richedit_check)("cell\n");
 213         break;
 214       default:
 215         assert(0);
 216     }
 217   } while(1);
 218   TRACE_(richedit_check)("Checking finished\n");
 219 }
 220
 221 /******************************************************************************
 222  * run_char_ofs
 223  *
 224  * Converts a character position relative to the start of the run to a
 225  * character position relative to the start of the document.
 226  */
 227
 228 int run_char_ofs( ME_Run *run, int ofs )
 229 {
 230     return run->para->nCharOfs + run->nCharOfs + ofs;
 231 }
 232
 233 /******************************************************************************
 234  * cursor_from_char_ofs
 235  *
 236  * Converts a character offset (relative to the start of the document) to
 237  * a cursor structure (which contains a run and a position relative to that
 238  * run).
 239  */
 240 void cursor_from_char_ofs( ME_TextEditor *editor, int char_ofs, ME_Cursor *cursor )
 241 {
 242     ME_Paragraph *para;
 243     ME_Run *run;
 244
 245     char_ofs = min( max( char_ofs, 0 ), ME_GetTextLength( editor ) );
 246
 247     /* Find the paragraph at the offset. */
 248     for (para = editor_first_para( editor );
 249          para_next( para )->nCharOfs <= char_ofs;
 250          para = para_next( para ))
 251         ;
 252
 253     char_ofs -= para->nCharOfs;
 254
 255     /* Find the run at the offset. */
 256     for (run = para_first_run( para );
 257          run_next( run ) && run_next( run )->nCharOfs <= char_ofs;
 258          run = run_next( run ))
 259         ;
 260
 261     char_ofs -= run->nCharOfs;
 262
 263     cursor->para = para;
 264     cursor->run = run;
 265     cursor->nOffset = char_ofs;
 266 }
 267
 268 /******************************************************************************
 269  * run_join
 270  *
 271  * Merges two adjacent runs, the one given as a parameter and the next one.
 272  */
 273 void run_join( ME_TextEditor *editor, ME_Run *run )
 274 {
 275   ME_Run *next = run_next( run );
 276   int i;
 277
 278   assert( run );
 279   assert( run->nCharOfs != -1 );
 280   para_mark_rewrap( editor, run->para );
 281
 282   /* Update all cursors so that they don't contain the soon deleted run */
 283   for (i = 0; i < editor->nCursors; i++)
 284   {
 285     if (editor->pCursors[i].run == next)
 286     {
 287       editor->pCursors[i].run = run;
 288       editor->pCursors[i].nOffset += run->len;
 289     }
 290   }
 291
 292   run->len += next->len;
 293   ME_Remove( run_get_di( next ) );
 294   ME_DestroyDisplayItem( run_get_di( next ) );
 295   ME_UpdateRunFlags( editor, run );
 296   ME_CheckCharOffsets( editor );
 297 }
 298
 299 /******************************************************************************
 300  * run_split
 301  *
 302  * Does the most basic job of splitting a run into two - it does not
 303  * update the positions and extents.
 304  */
 305 ME_Run *run_split( ME_TextEditor *editor, ME_Cursor *cursor )
 306 {
 307     ME_Run *run = cursor->run, *new_run;
 308     int i;
 309     int nOffset = cursor->nOffset;
 310
 311     assert( !(run->nFlags & MERF_NONTEXT) );
 312
 313     new_run = run_create( run->style, run->nFlags & MERF_SPLITMASK );
 314     new_run->nCharOfs = run->nCharOfs + nOffset;
 315     new_run->len = run->len - nOffset;
 316     new_run->para = run->para;
 317     run->len = nOffset;
 318     cursor->run = new_run;
 319     cursor->nOffset = 0;
 320
 321     ME_InsertBefore( run_get_di( run )->next, run_get_di( new_run ) );
 322
 323     ME_UpdateRunFlags( editor, run );
 324     ME_UpdateRunFlags( editor, new_run );
 325     for (i = 0; i < editor->nCursors; i++)
 326     {
 327         if (editor->pCursors[i].run == run &&
 328             editor->pCursors[i].nOffset >= nOffset)
 329         {
 330             editor->pCursors[i].run = new_run;
 331             editor->pCursors[i].nOffset -= nOffset;
 332         }
 333     }
 334     para_mark_rewrap( editor, run->para );
 335     return run;
 336 }
 337
 338 /******************************************************************************
 339  * run_create
 340  *
 341  * A helper function to create run structures quickly.
 342  */
 343 ME_Run *run_create( ME_Style *s, int flags )
 344 {
 345     ME_DisplayItem *item = ME_MakeDI( diRun );
 346     ME_Run *run = &item->member.run;
 347
 348     if (!item) return NULL;
 349
 350     ME_AddRefStyle( s );
 351     run->style = s;
 352     run->reobj = NULL;
 353     run->nFlags = flags;
 354     run->nCharOfs = -1;
 355     run->len = 0;
 356     run->para = NULL;
 357     run->num_glyphs = 0;
 358     run->max_glyphs = 0;
 359     run->glyphs = NULL;
 360     run->vis_attrs = NULL;
 361     run->advances = NULL;
 362     run->offsets = NULL;
 363     run->max_clusters = 0;
 364     run->clusters = NULL;
 365     return run;
 366 }
 367
 368 /******************************************************************************
 369  * run_insert
 370  *
 371  * Inserts a new run with given style, flags and content at a given position,
 372  * which is passed as a cursor structure (which consists of a run and
 373  * a run-relative character offset).
 374  */
 375 ME_Run *run_insert( ME_TextEditor *editor, ME_Cursor *cursor, ME_Style *style,
 376                     const WCHAR *str, int len, int flags )
 377 {
 378   ME_Run *insert_before = cursor->run, *run, *prev;
 379
 380   if (cursor->nOffset)
 381   {
 382     if (cursor->nOffset == insert_before->len)
 383     {
 384       insert_before = run_next_all_paras( insert_before );
 385       if (!insert_before) insert_before = cursor->run; /* Always insert before the final eop run */
 386     }
 387     else
 388     {
 389       run_split( editor, cursor );
 390       insert_before = cursor->run;
 391     }
 392   }
 393
 394   add_undo_delete_run( editor, insert_before->para->nCharOfs + insert_before->nCharOfs, len );
 395
 396   run = run_create( style, flags );
 397   run->nCharOfs = insert_before->nCharOfs;
 398   run->len = len;
 399   run->para = insert_before->para;
 400   ME_InsertString( run->para->text, run->nCharOfs, str, len );
 401   ME_InsertBefore( run_get_di( insert_before ), run_get_di( run ) );
 402   TRACE("Shift length:%d\n", len);
 403   editor_propagate_char_ofs( NULL, insert_before, len );
 404   para_mark_rewrap( editor, insert_before->para );
 405
 406   /* Move any cursors that were at the end of the previous run to the end of the inserted run */
 407   prev = run_prev_all_paras( run );
 408   if (prev)
 409   {
 410     int i;
 411
 412     for (i = 0; i < editor->nCursors; i++)
 413     {
 414       if (editor->pCursors[i].run == prev &&
 415           editor->pCursors[i].nOffset == prev->len)
 416       {
 417         editor->pCursors[i].run = run;
 418         editor->pCursors[i].nOffset = len;
 419       }
 420     }
 421   }
 422
 423   return run;
 424 }
 425
 426 static BOOL run_is_splittable( const ME_Run *run )
 427 {
 428     WCHAR *str = get_text( run, 0 ), *p;
 429     int i;
 430     BOOL found_ink = FALSE;
 431
 432     for (i = 0, p = str; i < run->len; i++, p++)
 433     {
 434         if (ME_IsWSpace( *p ))
 435         {
 436             if (found_ink) return TRUE;
 437         }
 438         else
 439             found_ink = TRUE;
 440     }
 441     return FALSE;
 442 }
 443
 444 static BOOL run_is_entirely_ws( const ME_Run *run )
 445 {
 446     WCHAR *str = get_text( run, 0 ), *p;
 447     int i;
 448
 449     for (i = 0, p = str; i < run->len; i++, p++)
 450         if (!ME_IsWSpace( *p )) return FALSE;
 451
 452     return TRUE;
 453 }
 454
 455 /******************************************************************************
 456  * ME_UpdateRunFlags
 457  *
 458  * Determine some of run attributes given its content (style, text content).
 459  * Some flags cannot be determined by this function (MERF_GRAPHICS,
 460  * MERF_ENDPARA)
 461  */
 462 void ME_UpdateRunFlags(ME_TextEditor *editor, ME_Run *run)
 463 {
 464   assert(run->nCharOfs >= 0);
 465
 466   if (RUN_IS_HIDDEN(run) || run->nFlags & MERF_TABLESTART)
 467     run->nFlags |= MERF_HIDDEN;
 468   else
 469     run->nFlags &= ~MERF_HIDDEN;
 470
 471   if (run_is_splittable( run ))
 472     run->nFlags |= MERF_SPLITTABLE;
 473   else
 474     run->nFlags &= ~MERF_SPLITTABLE;
 475
 476   if (!(run->nFlags & MERF_NOTEXT))
 477   {
 478     if (run_is_entirely_ws( run ))
 479       run->nFlags |= MERF_WHITESPACE | MERF_STARTWHITE | MERF_ENDWHITE;
 480     else
 481     {
 482       run->nFlags &= ~MERF_WHITESPACE;
 483
 484       if (ME_IsWSpace( *get_text( run, 0 ) ))
 485         run->nFlags |= MERF_STARTWHITE;
 486       else
 487         run->nFlags &= ~MERF_STARTWHITE;
 488
 489       if (ME_IsWSpace( *get_text( run, run->len - 1 ) ))
 490         run->nFlags |= MERF_ENDWHITE;
 491       else
 492         run->nFlags &= ~MERF_ENDWHITE;
 493     }
 494   }
 495   else
 496     run->nFlags &= ~(MERF_WHITESPACE | MERF_STARTWHITE | MERF_ENDWHITE);
 497 }
 498
 499 /******************************************************************************
 500  * ME_CharFromPointContext
 501  *
 502  * Returns a character position inside the run given a run-relative
 503  * pixel horizontal position.
 504  *
 505  * If closest is FALSE return the actual character
 506  * If closest is TRUE will round to the closest leading edge.
 507  * ie. if the second character is at pixel position 8 and third at 16 then for:
 508  * closest = FALSE cx = 0..7 return 0, cx = 8..15 return 1
 509  * closest = TRUE  cx = 0..3 return 0, cx = 4..11 return 1.
 510  */
 511 int ME_CharFromPointContext(ME_Context *c, int cx, ME_Run *run, BOOL closest, BOOL visual_order)
 512 {
 513   ME_String *mask_text = NULL;
 514   WCHAR *str;
 515   int fit = 0;
 516   SIZE sz, sz2, sz3;
 517   if (!run->len || cx <= 0)
 518     return 0;
 519
 520   if (run->nFlags & (MERF_TAB | MERF_ENDCELL))
 521   {
 522     if (!closest || cx < run->nWidth / 2) return 0;
 523     return 1;
 524   }
 525
 526   if (run->nFlags & MERF_GRAPHICS)
 527   {
 528     SIZE sz;
 529     ME_GetOLEObjectSize(c, run, &sz);
 530     if (!closest || cx < sz.cx / 2) return 0;
 531     return 1;
 532   }
 533
 534   if (run->para->nFlags & MEPF_COMPLEX)
 535   {
 536       int cp, trailing;
 537       if (visual_order && run->script_analysis.fRTL) cx = run->nWidth - cx - 1;
 538
 539       ScriptXtoCP( cx, run->len, run->num_glyphs, run->clusters, run->vis_attrs, run->advances, &run->script_analysis,
 540                    &cp, &trailing );
 541       TRACE("x %d cp %d trailing %d (run width %d) rtl %d log order %d\n", cx, cp, trailing, run->nWidth,
 542             run->script_analysis.fRTL, run->script_analysis.fLogicalOrder);
 543       return closest ? cp + trailing : cp;
 544   }
 545
 546   if (c->editor->cPasswordMask)
 547   {
 548     mask_text = ME_MakeStringR( c->editor->cPasswordMask, run->len );
 549     str = mask_text->szData;
 550   }
 551   else
 552     str = get_text( run, 0 );
 553
 554   select_style(c, run->style);
 555   GetTextExtentExPointW(c->hDC, str, run->len,
 556                         cx, &fit, NULL, &sz);
 557   if (closest && fit != run->len)
 558   {
 559     GetTextExtentPoint32W(c->hDC, str, fit, &sz2);
 560     GetTextExtentPoint32W(c->hDC, str, fit + 1, &sz3);
 561     if (cx >= (sz2.cx+sz3.cx)/2)
 562       fit = fit + 1;
 563   }
 564
 565   ME_DestroyString( mask_text );
 566
 567   return fit;
 568 }
 569
 570 int ME_CharFromPoint(ME_TextEditor *editor, int cx, ME_Run *run, BOOL closest, BOOL visual_order)
 571 {
 572     ME_Context c;
 573     int ret;
 574
 575     ME_InitContext( &c, editor, ITextHost_TxGetDC( editor->texthost ) );
 576     ret = ME_CharFromPointContext( &c, cx, run, closest, visual_order );
 577     ME_DestroyContext(&c);
 578     return ret;
 579 }
 580
 581 /******************************************************************************
 582  * ME_GetTextExtent
 583  *
 584  * Finds a width and a height of the text using a specified style
 585  */
 586 static void ME_GetTextExtent(ME_Context *c, LPCWSTR szText, int nChars, ME_Style *s, SIZE *size)
 587 {
 588     if (c->hDC)
 589     {
 590         select_style( c, s );
 591         GetTextExtentPoint32W( c->hDC, szText, nChars, size );
 592     }
 593     else
 594     {
 595         size->cx = 0;
 596         size->cy = 0;
 597     }
 598 }
 599
 600 /******************************************************************************
 601  * ME_PointFromCharContext
 602  *
 603  * Returns a run-relative pixel position given a run-relative character
 604  * position (character offset)
 605  */
 606 int ME_PointFromCharContext(ME_Context *c, ME_Run *pRun, int nOffset, BOOL visual_order)
 607 {
 608   SIZE size;
 609   ME_String *mask_text = NULL;
 610   WCHAR *str;
 611
 612   if (pRun->nFlags & MERF_GRAPHICS)
 613   {
 614     if (nOffset)
 615       ME_GetOLEObjectSize(c, pRun, &size);
 616     return nOffset != 0;
 617   } else if (pRun->nFlags & MERF_ENDPARA) {
 618     nOffset = 0;
 619   }
 620
 621   if (pRun->para->nFlags & MEPF_COMPLEX)
 622   {
 623       int x;
 624       ScriptCPtoX( nOffset, FALSE, pRun->len, pRun->num_glyphs, pRun->clusters,
 625                    pRun->vis_attrs, pRun->advances, &pRun->script_analysis, &x );
 626       if (visual_order && pRun->script_analysis.fRTL) x = pRun->nWidth - x - 1;
 627       return x;
 628   }
 629   if (c->editor->cPasswordMask)
 630   {
 631     mask_text = ME_MakeStringR(c->editor->cPasswordMask, pRun->len);
 632     str = mask_text->szData;
 633   }
 634   else
 635       str = get_text( pRun, 0 );
 636
 637   ME_GetTextExtent(c, str, nOffset, pRun->style, &size);
 638   ME_DestroyString( mask_text );
 639   return size.cx;
 640 }
 641
 642 /******************************************************************************
 643  * ME_PointFromChar
 644  *
 645  * Calls ME_PointFromCharContext after first creating a context.
 646  */
 647 int ME_PointFromChar(ME_TextEditor *editor, ME_Run *pRun, int nOffset, BOOL visual_order)
 648 {
 649     ME_Context c;
 650     int ret;
 651
 652     ME_InitContext(&c, editor, ITextHost_TxGetDC(editor->texthost));
 653     ret = ME_PointFromCharContext( &c, pRun, nOffset, visual_order );
 654     ME_DestroyContext(&c);
 655
 656     return ret;
 657 }
 658
 659 /******************************************************************************
 660  * ME_GetRunSizeCommon
 661  *
 662  * Finds width, height, ascent and descent of a run, up to given character
 663  * (nLen).
 664  */
 665 SIZE ME_GetRunSizeCommon(ME_Context *c, const ME_Paragraph *para, ME_Run *run, int nLen,
 666                          int startx, int *pAscent, int *pDescent)
 667 {
 668   SIZE size;
 669
 670   nLen = min( nLen, run->len );
 671
 672   if (run->nFlags & MERF_ENDPARA)
 673   {
 674       nLen = min( nLen, 1 );
 675       ME_GetTextExtent( c, L" ", nLen, run->style, &size );
 676   }
 677   else if (para->nFlags & MEPF_COMPLEX)
 678   {
 679       size.cx = run->nWidth;
 680   }
 681   else if (c->editor->cPasswordMask)
 682   {
 683     ME_String *szMasked = ME_MakeStringR(c->editor->cPasswordMask,nLen);
 684     ME_GetTextExtent(c, szMasked->szData, nLen,run->style, &size);
 685     ME_DestroyString(szMasked);
 686   }
 687   else
 688   {
 689     ME_GetTextExtent(c, get_text( run, 0 ), nLen, run->style, &size);
 690   }
 691   *pAscent = run->style->tm.tmAscent;
 692   *pDescent = run->style->tm.tmDescent;
 693   size.cy = *pAscent + *pDescent;
 694
 695   if (run->nFlags & MERF_TAB)
 696   {
 697     int pos = 0, i = 0, ppos, shift = 0;
 698     const PARAFORMAT2 *pFmt = &para->fmt;
 699
 700     if (c->editor->bEmulateVersion10 && /* v1.0 - 3.0 */
 701         pFmt->dwMask & PFM_TABLE && pFmt->wEffects & PFE_TABLE)
 702       /* The horizontal gap shifts the tab positions to leave the gap. */
 703       shift = pFmt->dxOffset * 2;
 704     do {
 705       if (i < pFmt->cTabCount)
 706       {
 707         /* Only one side of the horizontal gap is needed at the end of
 708          * the table row. */
 709         if (i == pFmt->cTabCount -1)
 710           shift = shift >> 1;
 711         pos = shift + (pFmt->rgxTabs[i]&0x00FFFFFF);
 712         i++;
 713       }
 714       else
 715       {
 716         pos += lDefaultTab - (pos % lDefaultTab);
 717       }
 718       ppos = ME_twips2pointsX(c, pos);
 719       if (ppos > startx + run->pt.x) {
 720         size.cx = ppos - startx - run->pt.x;
 721         break;
 722       }
 723     } while(1);
 724     size.cy = *pAscent + *pDescent;
 725     return size;
 726   }
 727   if (run->nFlags & MERF_GRAPHICS)
 728   {
 729     ME_GetOLEObjectSize(c, run, &size);
 730     if (size.cy > *pAscent)
 731       *pAscent = size.cy;
 732     /* descent is unchanged */
 733     return size;
 734   }
 735   return size;
 736 }
 737
 738 /******************************************************************************
 739  * ME_SetSelectionCharFormat
 740  *
 741  * Applies a style change, either to a current selection, or to insert cursor
 742  * (ie. the style next typed characters will use).
 743  */
 744 void ME_SetSelectionCharFormat(ME_TextEditor *editor, CHARFORMAT2W *pFmt)
 745 {
 746   if (!ME_IsSelection(editor))
 747   {
 748     ME_Style *s;
 749     if (!editor->pBuffer->pCharStyle)
 750       editor->pBuffer->pCharStyle = style_get_insert_style( editor, editor->pCursors );
 751     s = ME_ApplyStyle(editor, editor->pBuffer->pCharStyle, pFmt);
 752     ME_ReleaseStyle(editor->pBuffer->pCharStyle);
 753     editor->pBuffer->pCharStyle = s;
 754   } else {
 755     ME_Cursor *from, *to;
 756     ME_GetSelection(editor, &from, &to);
 757     ME_SetCharFormat(editor, from, to, pFmt);
 758   }
 759 }
 760
 761 /******************************************************************************
 762  * ME_SetCharFormat
 763  *
 764  * Applies a style change to the specified part of the text
 765  *
 766  * The start and end cursors specify the part of the text.  These cursors will
 767  * be updated to stay valid, but this function may invalidate other
 768  * non-selection cursors. The end cursor may be NULL to specify all the text
 769  * following the start cursor.
 770  *
 771  * If no text is selected, then nothing is done.
 772  */
 773 void ME_SetCharFormat( ME_TextEditor *editor, ME_Cursor *start, ME_Cursor *end, CHARFORMAT2W *fmt )
 774 {
 775   ME_Run *run, *start_run = start->run, *end_run = NULL;
 776
 777   if (end && start->run == end->run && start->nOffset == end->nOffset)
 778     return;
 779
 780   if (start->nOffset == start->run->len)
 781     start_run = run_next_all_paras( start->run );
 782   else if (start->nOffset)
 783   {
 784     /* run_split() may or may not update the cursors, depending on whether they
 785      * are selection cursors, but we need to make sure they are valid. */
 786     int split_offset = start->nOffset;
 787     ME_Run *split_run = run_split( editor, start );
 788     start_run = start->run;
 789     if (end && end->run == split_run)
 790     {
 791       end->run = start->run;
 792       end->nOffset -= split_offset;
 793     }
 794   }
 795
 796   if (end)
 797   {
 798     if (end->nOffset == end->run->len)
 799       end_run = run_next_all_paras( end->run );
 800     else
 801     {
 802       if (end->nOffset) run_split( editor, end );
 803       end_run = end->run;
 804     }
 805   }
 806
 807   for (run = start_run; run != end_run; run = run_next_all_paras( run ))
 808   {
 809     ME_Style *new_style = ME_ApplyStyle( editor, run->style, fmt );
 810     ME_Paragraph *para = run->para;
 811
 812     add_undo_set_char_fmt( editor, para->nCharOfs + run->nCharOfs,
 813                            run->len, &run->style->fmt );
 814     ME_ReleaseStyle( run->style );
 815     run->style = new_style;
 816
 817     /* The para numbering style depends on the eop style */
 818     if ((run->nFlags & MERF_ENDPARA) && para->para_num.style)
 819     {
 820       ME_ReleaseStyle(para->para_num.style);
 821       para->para_num.style = NULL;
 822     }
 823     para_mark_rewrap( editor, para );
 824   }
 825 }
 826
 827 static void run_copy_char_fmt( ME_Run *run, CHARFORMAT2W *fmt )
 828 {
 829     ME_CopyCharFormat( fmt, &run->style->fmt );
 830 }
 831
 832 /******************************************************************************
 833  * ME_GetDefaultCharFormat
 834  *
 835  * Retrieves the current default character style (the one applied where no
 836  * other style was applied) .
 837  */
 838 void ME_GetDefaultCharFormat(ME_TextEditor *editor, CHARFORMAT2W *pFmt)
 839 {
 840   ME_CopyCharFormat(pFmt, &editor->pBuffer->pDefaultStyle->fmt);
 841 }
 842
 843 /******************************************************************************
 844  * ME_GetSelectionCharFormat
 845  *
 846  * If selection exists, it returns all style elements that are set consistently
 847  * in the whole selection. If not, it just returns the current style.
 848  */
 849 void ME_GetSelectionCharFormat(ME_TextEditor *editor, CHARFORMAT2W *pFmt)
 850 {
 851   ME_Cursor *from, *to;
 852   if (!ME_IsSelection(editor) && editor->pBuffer->pCharStyle)
 853   {
 854     ME_CopyCharFormat(pFmt, &editor->pBuffer->pCharStyle->fmt);
 855     return;
 856   }
 857   ME_GetSelection(editor, &from, &to);
 858   ME_GetCharFormat(editor, from, to, pFmt);
 859 }
 860
 861 /******************************************************************************
 862  * ME_GetCharFormat
 863  *
 864  * Returns the style consisting of those attributes which are consistently set
 865  * in the whole character range.
 866  */
 867 void ME_GetCharFormat( ME_TextEditor *editor, const ME_Cursor *from,
 868                        const ME_Cursor *to, CHARFORMAT2W *fmt )
 869 {
 870   ME_Run *run, *run_end, *prev_run;
 871   CHARFORMAT2W tmp;
 872
 873   run = from->run;
 874   /* special case - if selection is empty, take previous char's formatting */
 875   if (from->run == to->run && from->nOffset == to->nOffset)
 876   {
 877     if (!from->nOffset && (prev_run = run_prev( run ))) run = prev_run;
 878     run_copy_char_fmt( run, fmt );
 879     return;
 880   }
 881
 882   run_end = to->run;
 883   if (!to->nOffset) run_end = run_prev_all_paras( run_end );
 884
 885   run_copy_char_fmt( run, fmt );
 886
 887   if (run == run_end) return;
 888
 889   do {
 890     /* FIXME add more style feature comparisons */
 891     DWORD dwAttribs = CFM_SIZE | CFM_FACE | CFM_COLOR | CFM_UNDERLINETYPE;
 892     DWORD dwEffects = CFM_BOLD | CFM_ITALIC | CFM_UNDERLINE | CFM_STRIKEOUT | CFM_PROTECTED | CFM_LINK | CFM_SUPERSCRIPT;
 893
 894     run = run_next_all_paras( run );
 895
 896     memset( &tmp, 0, sizeof(tmp) );
 897     tmp.cbSize = sizeof(tmp);
 898     run_copy_char_fmt( run, &tmp );
 899
 900     assert((tmp.dwMask & dwAttribs) == dwAttribs);
 901     /* reset flags that differ */
 902
 903     if (fmt->yHeight != tmp.yHeight) fmt->dwMask &= ~CFM_SIZE;
 904     if (fmt->dwMask & CFM_FACE)
 905     {
 906       if (!(tmp.dwMask & CFM_FACE))
 907         fmt->dwMask &= ~CFM_FACE;
 908       else if (wcscmp( fmt->szFaceName, tmp.szFaceName ) ||
 909                fmt->bPitchAndFamily != tmp.bPitchAndFamily)
 910         fmt->dwMask &= ~CFM_FACE;
 911     }
 912     if (fmt->yHeight != tmp.yHeight) fmt->dwMask &= ~CFM_SIZE;
 913     if (fmt->bUnderlineType != tmp.bUnderlineType) fmt->dwMask &= ~CFM_UNDERLINETYPE;
 914     if (fmt->dwMask & CFM_COLOR)
 915     {
 916       if (!((fmt->dwEffects&CFE_AUTOCOLOR) & (tmp.dwEffects&CFE_AUTOCOLOR)))
 917       {
 918         if (fmt->crTextColor != tmp.crTextColor)
 919           fmt->dwMask &= ~CFM_COLOR;
 920       }
 921     }
 922
 923     fmt->dwMask &= ~((fmt->dwEffects ^ tmp.dwEffects) & dwEffects);
 924     fmt->dwEffects = tmp.dwEffects;
 925
 926   } while(run != run_end);
 927 }