dlls/riched20/paint.c

   1 /*
   2  * RichEdit - painting functions
   3  *
   4  * Copyright 2004 by Krzysztof Foltman
   5  * Copyright 2005 by Phil Krylov
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  20  */
  21
  22 #include "editor.h"
  23
  24 WINE_DEFAULT_DEBUG_CHANNEL(richedit);
  25
  26 void ME_PaintContent(ME_TextEditor *editor, HDC hDC, BOOL bOnlyNew, const RECT *rcUpdate) {
  27   ME_DisplayItem *item;
  28   ME_Context c;
  29   int yoffset;
  30
  31   editor->nSequence++;
  32   yoffset = ME_GetYScrollPos(editor);
  33   ME_InitContext(&c, editor, hDC);
  34   SetBkMode(hDC, TRANSPARENT);
  35   ME_MoveCaret(editor);
  36   item = editor->pBuffer->pFirst->next;
  37   c.pt.y -= yoffset;
  38   while(item != editor->pBuffer->pLast) {
  39     int ye;
  40     assert(item->type == diParagraph);
  41     ye = c.pt.y + item->member.para.nHeight;
  42     if (!bOnlyNew || (item->member.para.nFlags & MEPF_REPAINT))
  43     {
  44       BOOL bPaint = (rcUpdate == NULL);
  45       if (rcUpdate)
  46         bPaint = c.pt.y<rcUpdate->bottom &&
  47           c.pt.y+item->member.para.nHeight>rcUpdate->top;
  48       if (bPaint)
  49       {
  50         ME_DrawParagraph(&c, item);
  51         if (!rcUpdate || (rcUpdate->top<=c.pt.y && rcUpdate->bottom>=ye))
  52           item->member.para.nFlags &= ~MEPF_REPAINT;
  53       }
  54     }
  55     c.pt.y = ye;
  56     item = item->member.para.next_para;
  57   }
  58   if (c.pt.y<c.rcView.bottom) {
  59     RECT rc;
  60     int xs = c.rcView.left, xe = c.rcView.right;
  61     int ys = c.pt.y, ye = c.rcView.bottom;
  62
  63     if (bOnlyNew)
  64     {
  65       int y1 = editor->nTotalLength-yoffset, y2 = editor->nLastTotalLength-yoffset;
  66       if (y1<y2)
  67         ys = y1, ye = y2+1;
  68       else
  69         ys = ye;
  70     }
  71
  72     if (rcUpdate && ys!=ye)
  73     {
  74       xs = rcUpdate->left, xe = rcUpdate->right;
  75       if (rcUpdate->top > ys)
  76         ys = rcUpdate->top;
  77       if (rcUpdate->bottom < ye)
  78         ye = rcUpdate->bottom;
  79     }
  80
  81     if (ye>ys) {
  82       rc.left = xs;
  83       rc.top = ys;
  84       rc.right = xe;
  85       rc.bottom = ye;
  86       FillRect(hDC, &rc, c.editor->hbrBackground);
  87     }
  88     if (ys == c.pt.y) /* don't overwrite the top bar */
  89       ys++;
  90   }
  91   if (editor->nTotalLength != editor->nLastTotalLength)
  92     ME_SendRequestResize(editor, FALSE);
  93   editor->nLastTotalLength = editor->nTotalLength;
  94   ME_DestroyContext(&c);
  95 }
  96
  97 void ME_Repaint(ME_TextEditor *editor)
  98 {
  99   if (ME_WrapMarkedParagraphs(editor))
 100   {
 101     ME_UpdateScrollBar(editor);
 102     FIXME("ME_Repaint had to call ME_WrapMarkedParagraphs\n");
 103   }
 104   ME_SendOldNotify(editor, EN_UPDATE);
 105   UpdateWindow(editor->hWnd);
 106 }
 107
 108 void ME_UpdateRepaint(ME_TextEditor *editor)
 109 {
 110   /* Should be called whenever the contents of the control have changed */
 111   ME_Cursor *pCursor;
 112
 113   if (ME_WrapMarkedParagraphs(editor))
 114     ME_UpdateScrollBar(editor);
 115
 116   /* Ensure that the cursor is visible */
 117   pCursor = &editor->pCursors[0];
 118   ME_EnsureVisible(editor, pCursor->pRun);
 119
 120   /* send EN_CHANGE if the event mask asks for it */
 121   if(editor->nEventMask & ENM_CHANGE)
 122   {
 123     editor->nEventMask &= ~ENM_CHANGE;
 124     ME_SendOldNotify(editor, EN_CHANGE);
 125     editor->nEventMask |= ENM_CHANGE;
 126   }
 127   ME_Repaint(editor);
 128   ME_SendSelChange(editor);
 129 }
 130
 131 void
 132 ME_RewrapRepaint(ME_TextEditor *editor)
 133 {
 134   /* RewrapRepaint should be called whenever the control has changed in
 135    * looks, but not content. Like resizing. */
 136
 137   ME_MarkAllForWrapping(editor);
 138   ME_WrapMarkedParagraphs(editor);
 139   ME_UpdateScrollBar(editor);
 140
 141   ME_Repaint(editor);
 142 }
 143
 144
 145 static void ME_DrawTextWithStyle(ME_Context *c, int x, int y, LPCWSTR szText, int nChars,
 146   ME_Style *s, int *width, int nSelFrom, int nSelTo, int ymin, int cy) {
 147   HDC hDC = c->hDC;
 148   HGDIOBJ hOldFont;
 149   COLORREF rgbOld, rgbBack;
 150   int yOffset = 0, yTwipsOffset = 0;
 151   hOldFont = ME_SelectStyleFont(c->editor, hDC, s);
 152   rgbBack = ME_GetBackColor(c->editor);
 153   if ((s->fmt.dwMask & CFM_LINK) && (s->fmt.dwEffects & CFE_LINK))
 154     rgbOld = SetTextColor(hDC, RGB(0,0,255));
 155   else if ((s->fmt.dwMask & CFM_COLOR) && (s->fmt.dwEffects & CFE_AUTOCOLOR))
 156     rgbOld = SetTextColor(hDC, GetSysColor(COLOR_WINDOWTEXT));
 157   else
 158     rgbOld = SetTextColor(hDC, s->fmt.crTextColor);
 159   if ((s->fmt.dwMask & s->fmt.dwEffects) & CFM_OFFSET) {
 160     yTwipsOffset = s->fmt.yOffset;
 161   }
 162   if ((s->fmt.dwMask & s->fmt.dwEffects) & (CFM_SUPERSCRIPT | CFM_SUBSCRIPT)) {
 163     if (s->fmt.dwEffects & CFE_SUPERSCRIPT) yTwipsOffset = s->fmt.yHeight/3;
 164     if (s->fmt.dwEffects & CFE_SUBSCRIPT) yTwipsOffset = -s->fmt.yHeight/12;
 165   }
 166   if (yTwipsOffset)
 167   {
 168     int numerator = 1;
 169     int denominator = 1;
 170
 171     if (c->editor->nZoomNumerator)
 172     {
 173       numerator = c->editor->nZoomNumerator;
 174       denominator = c->editor->nZoomDenominator;
 175     }
 176     yOffset = yTwipsOffset * GetDeviceCaps(hDC, LOGPIXELSY) * numerator / denominator / 1440;
 177   }
 178   ExtTextOutW(hDC, x, y-yOffset, 0, NULL, szText, nChars, NULL);
 179   if (width) {
 180     SIZE sz;
 181     GetTextExtentPoint32W(hDC, szText, nChars, &sz);
 182     *width = sz.cx;
 183   }
 184   if (nSelFrom < nChars && nSelTo >= 0 && nSelFrom<nSelTo)
 185   {
 186     SIZE sz;
 187     if (nSelFrom < 0) nSelFrom = 0;
 188     if (nSelTo > nChars) nSelTo = nChars;
 189     GetTextExtentPoint32W(hDC, szText, nSelFrom, &sz);
 190     x += sz.cx;
 191     GetTextExtentPoint32W(hDC, szText+nSelFrom, nSelTo-nSelFrom, &sz);
 192
 193     /* Invert selection if not hidden by EM_HIDESELECTION */
 194     if (c->editor->bHideSelection == FALSE)
 195         PatBlt(hDC, x, ymin, sz.cx, cy, DSTINVERT);
 196   }
 197   SetTextColor(hDC, rgbOld);
 198   ME_UnselectStyleFont(c->editor, hDC, s, hOldFont);
 199 }
 200
 201 static void ME_DebugWrite(HDC hDC, const POINT *pt, LPCWSTR szText) {
 202   int align = SetTextAlign(hDC, TA_LEFT|TA_TOP);
 203   HGDIOBJ hFont = SelectObject(hDC, GetStockObject(DEFAULT_GUI_FONT));
 204   COLORREF color = SetTextColor(hDC, RGB(128,128,128));
 205   TextOutW(hDC, pt->x, pt->y, szText, lstrlenW(szText));
 206   SelectObject(hDC, hFont);
 207   SetTextAlign(hDC, align);
 208   SetTextColor(hDC, color);
 209 }
 210
 211 static void ME_DrawGraphics(ME_Context *c, int x, int y, ME_Run *run,
 212                             ME_Paragraph *para, BOOL selected) {
 213   SIZE sz;
 214   int xs, ys, xe, ye, h, ym, width, eyes;
 215   ME_GetGraphicsSize(c->editor, run, &sz);
 216   xs = run->pt.x;
 217   ys = y-sz.cy;
 218   xe = xs+sz.cx;
 219   ye = y;
 220   h = ye-ys;
 221   ym = ys+h/4;
 222   width = sz.cx;
 223   eyes = width/8;
 224   /* draw a smiling face :) */
 225   Ellipse(c->hDC, xs, ys, xe, ye);
 226   Ellipse(c->hDC, xs+width/8, ym, x+width/8+eyes, ym+eyes);
 227   Ellipse(c->hDC, xs+7*width/8-eyes, ym, xs+7*width/8, ym+eyes);
 228   MoveToEx(c->hDC, xs+width/8, ys+3*h/4-eyes, NULL);
 229   LineTo(c->hDC, xs+width/8, ys+3*h/4);
 230   LineTo(c->hDC, xs+7*width/8, ys+3*h/4);
 231   LineTo(c->hDC, xs+7*width/8, ys+3*h/4-eyes);
 232   if (selected)
 233   {
 234     /* descent is usually (always?) 0 for graphics */
 235     PatBlt(c->hDC, x, y-run->nAscent, sz.cx, run->nAscent+run->nDescent, DSTINVERT);
 236   }
 237 }
 238
 239 static void ME_DrawRun(ME_Context *c, int x, int y, ME_DisplayItem *rundi, ME_Paragraph *para)
 240 {
 241   ME_Run *run = &rundi->member.run;
 242   ME_DisplayItem *start = ME_FindItemBack(rundi, diStartRow);
 243   int runofs = run->nCharOfs+para->nCharOfs;
 244   int nSelFrom, nSelTo;
 245   const WCHAR wszSpace[] = {' ', 0};
 246
 247   if (run->nFlags & MERF_HIDDEN)
 248     return;
 249
 250   ME_GetSelection(c->editor, &nSelFrom, &nSelTo);
 251
 252   /* Draw selected end-of-paragraph mark */
 253   if (run->nFlags & MERF_ENDPARA && runofs >= nSelFrom && runofs < nSelTo)
 254     ME_DrawTextWithStyle(c, x, y, wszSpace, 1, run->style, NULL, 0, 1,
 255                          c->pt.y + start->member.row.nYPos,
 256                          start->member.row.nHeight);
 257
 258   /* you can always comment it out if you need visible paragraph marks */
 259   if (run->nFlags & (MERF_ENDPARA | MERF_TAB | MERF_CELL))
 260     return;
 261
 262   if (run->nFlags & MERF_GRAPHICS)
 263     ME_DrawGraphics(c, x, y, run, para, (runofs >= nSelFrom) && (runofs < nSelTo));
 264   else
 265   {
 266     if (c->editor->cPasswordMask)
 267     {
 268       ME_String *szMasked = ME_MakeStringR(c->editor->cPasswordMask,ME_StrVLen(run->strText));
 269       ME_DrawTextWithStyle(c, x, y,
 270         szMasked->szData, ME_StrVLen(szMasked), run->style, NULL,
 271         nSelFrom-runofs,nSelTo-runofs, c->pt.y+start->member.row.nYPos, start->member.row.nHeight);
 272       ME_DestroyString(szMasked);
 273     }
 274     else
 275       ME_DrawTextWithStyle(c, x, y,
 276         run->strText->szData, ME_StrVLen(run->strText), run->style, NULL,
 277         nSelFrom-runofs,nSelTo-runofs, c->pt.y+start->member.row.nYPos, start->member.row.nHeight);
 278     }
 279 }
 280
 281 COLORREF ME_GetBackColor(const ME_TextEditor *editor)
 282 {
 283 /* Looks like I was seriously confused
 284     return GetSysColor((GetWindowLong(editor->hWnd, GWL_STYLE) & ES_READONLY) ? COLOR_3DFACE: COLOR_WINDOW);
 285 */
 286   if (editor->rgbBackColor == -1)
 287     return GetSysColor(COLOR_WINDOW);
 288   else
 289     return editor->rgbBackColor;
 290 }
 291
 292 void ME_DrawParagraph(ME_Context *c, ME_DisplayItem *paragraph) {
 293   int align = SetTextAlign(c->hDC, TA_BASELINE);
 294   ME_DisplayItem *p;
 295   ME_Run *run;
 296   ME_Paragraph *para = NULL;
 297   RECT rc, rcPara;
 298   int y = c->pt.y;
 299   int height = 0, baseline = 0, no=0, pno = 0;
 300   int xs, xe;
 301   int visible = 0;
 302   int nMargWidth = 0;
 303
 304   c->pt.x = c->rcView.left;
 305   rcPara.left = c->rcView.left;
 306   rcPara.right = c->rcView.right;
 307   for (p = paragraph; p!=paragraph->member.para.next_para; p = p->next) {
 308     switch(p->type) {
 309       case diParagraph:
 310         para = &p->member.para;
 311         break;
 312       case diStartRow:
 313         assert(para);
 314         nMargWidth = (pno==0?para->nFirstMargin:para->nLeftMargin);
 315         xs = c->rcView.left+nMargWidth;
 316         xe = c->rcView.right-para->nRightMargin;
 317         y += height;
 318         rcPara.top = y;
 319         rcPara.bottom = y+p->member.row.nHeight;
 320         visible = RectVisible(c->hDC, &rcPara);
 321         if (visible) {
 322           HBRUSH hbr;
 323           hbr = CreateSolidBrush(ME_GetBackColor(c->editor));
 324           /* left margin */
 325           rc.left = c->rcView.left;
 326           rc.right = c->rcView.left+nMargWidth;
 327           rc.top = y;
 328           rc.bottom = y+p->member.row.nHeight;
 329           FillRect(c->hDC, &rc, hbr/* c->hbrMargin */);
 330           /* right margin */
 331           rc.left = xe;
 332           rc.right = c->rcView.right;
 333           FillRect(c->hDC, &rc, hbr/* c->hbrMargin */);
 334           rc.left = c->rcView.left+nMargWidth;
 335           rc.right = xe;
 336           FillRect(c->hDC, &rc, hbr);
 337           DeleteObject(hbr);
 338         }
 339         if (me_debug)
 340         {
 341           const WCHAR wszRowDebug[] = {'r','o','w','[','%','d',']',0};
 342           WCHAR buf[128];
 343           POINT pt = c->pt;
 344           wsprintfW(buf, wszRowDebug, no);
 345           pt.y = 12+y;
 346           ME_DebugWrite(c->hDC, &pt, buf);
 347         }
 348
 349         height = p->member.row.nHeight;
 350         baseline = p->member.row.nBaseline;
 351         pno++;
 352         break;
 353       case diRun:
 354         assert(para);
 355         run = &p->member.run;
 356         if (visible && me_debug) {
 357           rc.left = c->rcView.left+run->pt.x;
 358           rc.right = c->rcView.left+run->pt.x+run->nWidth;
 359           rc.top = c->pt.y+run->pt.y;
 360           rc.bottom = c->pt.y+run->pt.y+height;
 361           TRACE("rc = (%d, %d, %d, %d)\n", rc.left, rc.top, rc.right, rc.bottom);
 362           if (run->nFlags & MERF_SKIPPED)
 363             DrawFocusRect(c->hDC, &rc);
 364           else
 365             FrameRect(c->hDC, &rc, GetSysColorBrush(COLOR_GRAYTEXT));
 366         }
 367         if (visible)
 368           ME_DrawRun(c, run->pt.x, c->pt.y+run->pt.y+baseline, p, &paragraph->member.para);
 369         if (me_debug)
 370         {
 371           /* I'm using %ls, hope wsprintfW is not going to use wrong (4-byte) WCHAR version */
 372           const WCHAR wszRunDebug[] = {'[','%','d',':','%','x',']',' ','%','l','s',0};
 373           WCHAR buf[2560];
 374           POINT pt;
 375           pt.x = run->pt.x;
 376           pt.y = c->pt.y + run->pt.y;
 377           wsprintfW(buf, wszRunDebug, no, p->member.run.nFlags, p->member.run.strText->szData);
 378           ME_DebugWrite(c->hDC, &pt, buf);
 379         }
 380         /* c->pt.x += p->member.run.nWidth; */
 381         break;
 382       default:
 383         break;
 384     }
 385     no++;
 386   }
 387   SetTextAlign(c->hDC, align);
 388 }
 389
 390 void ME_ScrollAbs(ME_TextEditor *editor, int absY)
 391 {
 392   ME_Scroll(editor, absY, 1);
 393 }
 394
 395 void ME_ScrollUp(ME_TextEditor *editor, int cy)
 396 {
 397   ME_Scroll(editor, cy, 2);
 398 }
 399
 400 void ME_ScrollDown(ME_TextEditor *editor, int cy)
 401 {
 402   ME_Scroll(editor, cy, 3);
 403 }
 404
 405 void ME_Scroll(ME_TextEditor *editor, int value, int type)
 406 {
 407   SCROLLINFO si;
 408   int nOrigPos, nNewPos, nActualScroll;
 409
 410   nOrigPos = ME_GetYScrollPos(editor);
 411
 412   si.cbSize = sizeof(SCROLLINFO);
 413   si.fMask = SIF_POS;
 414
 415   switch (type)
 416   {
 417     case 1:
 418       /*Scroll absolutly*/
 419       si.nPos = value;
 420       break;
 421     case 2:
 422       /* Scroll up - towards the beginning of the document */
 423       si.nPos = nOrigPos - value;
 424       break;
 425     case 3:
 426       /* Scroll down - towards the end of the document */
 427       si.nPos = nOrigPos + value;
 428       break;
 429     default:
 430       FIXME("ME_Scroll called incorrectly\n");
 431       si.nPos = 0;
 432   }
 433
 434   nNewPos = SetScrollInfo(editor->hWnd, SB_VERT, &si, editor->bRedraw);
 435   nActualScroll = nOrigPos - nNewPos;
 436   if (editor->bRedraw)
 437   {
 438     if (abs(nActualScroll) > editor->sizeWindow.cy)
 439       InvalidateRect(editor->hWnd, NULL, TRUE);
 440     else
 441       ScrollWindowEx(editor->hWnd, 0, nActualScroll, NULL, NULL, NULL, NULL, SW_INVALIDATE);
 442     ME_Repaint(editor);
 443   }
 444
 445   ME_UpdateScrollBar(editor);
 446 }
 447
 448
 449  void ME_UpdateScrollBar(ME_TextEditor *editor)
 450 {
 451   /* Note that this is the only funciton that should ever call SetScrolLInfo
 452    * with SIF_PAGE or SIF_RANGE. SetScrollPos and SetScrollRange should never
 453    * be used at all. */
 454
 455   HWND hWnd;
 456   SCROLLINFO si;
 457   BOOL bScrollBarWasVisible,bScrollBarWillBeVisible;
 458
 459   if (ME_WrapMarkedParagraphs(editor))
 460     FIXME("ME_UpdateScrollBar had to call ME_WrapMarkedParagraphs\n");
 461
 462   hWnd = editor->hWnd;
 463   si.cbSize = sizeof(si);
 464   bScrollBarWasVisible = ME_GetYScrollVisible(editor);
 465   bScrollBarWillBeVisible = editor->nHeight > editor->sizeWindow.cy;
 466
 467   if (bScrollBarWasVisible != bScrollBarWillBeVisible)
 468   {
 469     ShowScrollBar(hWnd, SB_VERT, bScrollBarWillBeVisible);
 470     ME_MarkAllForWrapping(editor);
 471     ME_WrapMarkedParagraphs(editor);
 472   }
 473
 474   si.fMask = SIF_PAGE | SIF_RANGE;
 475   if (GetWindowLongW(hWnd, GWL_STYLE) & ES_DISABLENOSCROLL)
 476     si.fMask |= SIF_DISABLENOSCROLL;
 477
 478   si.nMin = 0;
 479   si.nMax = editor->nTotalLength;
 480
 481   si.nPage = editor->sizeWindow.cy;
 482
 483   TRACE("min=%d max=%d page=%d\n", si.nMin, si.nMax, si.nPage);
 484   SetScrollInfo(hWnd, SB_VERT, &si, TRUE);
 485 }
 486
 487 int ME_GetYScrollPos(ME_TextEditor *editor)
 488 {
 489   SCROLLINFO si;
 490   si.cbSize = sizeof(si);
 491   si.fMask = SIF_POS;
 492   GetScrollInfo(editor->hWnd, SB_VERT, &si);
 493   return si.nPos;
 494 }
 495
 496 BOOL ME_GetYScrollVisible(ME_TextEditor *editor)
 497 { /* Returns true if the scrollbar is visible */
 498   SCROLLBARINFO sbi;
 499   sbi.cbSize = sizeof(sbi);
 500   GetScrollBarInfo(editor->hWnd, OBJID_VSCROLL, &sbi);
 501   return ((sbi.rgstate[0] & STATE_SYSTEM_INVISIBLE) == 0);
 502 }
 503
 504 void ME_EnsureVisible(ME_TextEditor *editor, ME_DisplayItem *pRun)
 505 {
 506   ME_DisplayItem *pRow = ME_FindItemBack(pRun, diStartRow);
 507   ME_DisplayItem *pPara = ME_FindItemBack(pRun, diParagraph);
 508   int y, yrel, yheight, yold;
 509
 510   assert(pRow);
 511   assert(pPara);
 512
 513   y = pPara->member.para.nYPos+pRow->member.row.nYPos;
 514   yheight = pRow->member.row.nHeight;
 515   yold = ME_GetYScrollPos(editor);
 516   yrel = y - yold;
 517
 518   if (y < yold)
 519     ME_ScrollAbs(editor,y);
 520   else if (yrel + yheight > editor->sizeWindow.cy)
 521     ME_ScrollAbs(editor,y+yheight-editor->sizeWindow.cy);
 522 }
 523
 524
 525 void
 526 ME_InvalidateFromOfs(ME_TextEditor *editor, int nCharOfs)
 527 {
 528   RECT rc;
 529   int x, y, height;
 530   ME_Cursor tmp;
 531
 532   ME_RunOfsFromCharOfs(editor, nCharOfs, &tmp.pRun, &tmp.nOffset);
 533   ME_GetCursorCoordinates(editor, &tmp, &x, &y, &height);
 534
 535   rc.left = 0;
 536   rc.top = y;
 537   rc.bottom = y + height;
 538   rc.right = editor->rcFormat.right;
 539   InvalidateRect(editor->hWnd, &rc, FALSE);
 540 }
 541
 542
 543 void
 544 ME_InvalidateSelection(ME_TextEditor *editor)
 545 {
 546   ME_DisplayItem *para1, *para2;
 547   int nStart, nEnd;
 548   int len = ME_GetTextLength(editor);
 549
 550   ME_GetSelection(editor, &nStart, &nEnd);
 551   /* if both old and new selection are 0-char (= caret only), then
 552   there's no (inverted) area to be repainted, neither old nor new */
 553   if (nStart == nEnd && editor->nLastSelStart == editor->nLastSelEnd)
 554     return;
 555   ME_WrapMarkedParagraphs(editor);
 556   ME_GetSelectionParas(editor, &para1, &para2);
 557   assert(para1->type == diParagraph);
 558   assert(para2->type == diParagraph);
 559   /* last selection markers aren't always updated, which means
 560   they can point past the end of the document */
 561   if (editor->nLastSelStart > len)
 562     editor->nLastSelEnd = len;
 563   if (editor->nLastSelEnd > len)
 564     editor->nLastSelEnd = len;
 565
 566   /* if the start part of selection is being expanded or contracted... */
 567   if (nStart < editor->nLastSelStart) {
 568     ME_MarkForPainting(editor, para1, ME_FindItemFwd(editor->pLastSelStartPara, diParagraphOrEnd));
 569   } else
 570   if (nStart > editor->nLastSelStart) {
 571     ME_MarkForPainting(editor, editor->pLastSelStartPara, ME_FindItemFwd(para1, diParagraphOrEnd));
 572   }
 573
 574   /* if the end part of selection is being contracted or expanded... */
 575   if (nEnd < editor->nLastSelEnd) {
 576     ME_MarkForPainting(editor, para2, ME_FindItemFwd(editor->pLastSelEndPara, diParagraphOrEnd));
 577   } else
 578   if (nEnd > editor->nLastSelEnd) {
 579     ME_MarkForPainting(editor, editor->pLastSelEndPara, ME_FindItemFwd(para2, diParagraphOrEnd));
 580   }
 581
 582   ME_InvalidateMarkedParagraphs(editor);
 583   /* remember the last invalidated position */
 584   ME_GetSelection(editor, &editor->nLastSelStart, &editor->nLastSelEnd);
 585   ME_GetSelectionParas(editor, &editor->pLastSelStartPara, &editor->pLastSelEndPara);
 586   assert(editor->pLastSelStartPara->type == diParagraph);
 587   assert(editor->pLastSelEndPara->type == diParagraph);
 588 }
 589
 590 void
 591 ME_QueueInvalidateFromCursor(ME_TextEditor *editor, int nCursor)
 592 {
 593   editor->nInvalidOfs = ME_GetCursorOfs(editor, nCursor);
 594 }
 595
 596
 597 BOOL
 598 ME_SetZoom(ME_TextEditor *editor, int numerator, int denominator)
 599 {
 600   /* TODO: Zoom images and objects */
 601
 602   if (numerator != 0)
 603   {
 604     if (denominator == 0)
 605       return FALSE;
 606     if (1.0 / 64.0 > (float)numerator / (float)denominator
 607         || (float)numerator / (float)denominator > 64.0)
 608       return FALSE;
 609   }
 610
 611   editor->nZoomNumerator = numerator;
 612   editor->nZoomDenominator = denominator;
 613
 614   ME_RewrapRepaint(editor);
 615   return TRUE;
 616 }