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