richedit: Avoid scanning all text for paragraphs to invalidate.

dlls/riched20/editor.h

@@ -187,7 +187,7 @@ void ME_DestroyContext(ME_Context *c) DECLSPEC_HIDDEN;
 
 /* wrap.c */
 BOOL ME_WrapMarkedParagraphs(ME_TextEditor *editor) DECLSPEC_HIDDEN;
-void ME_InvalidateMarkedParagraphs(ME_TextEditor *editor) DECLSPEC_HIDDEN;
+void ME_InvalidateMarkedParagraphs(ME_TextEditor *editor, ME_DisplayItem *start_para, ME_DisplayItem *end_para) DECLSPEC_HIDDEN;
 void ME_SendRequestResize(ME_TextEditor *editor, BOOL force) DECLSPEC_HIDDEN;
 
 /* para.c */

dlls/riched20/paint.c

@@ -73,13 +73,7 @@ void ME_PaintContent(ME_TextEditor *editor, HDC hDC, const RECT *rcUpdate)
 
     /* Draw the paragraph if any of the paragraph is in the update region. */
     if (ys < rcUpdate->bottom && ye > rcUpdate->top)
-    {
       ME_DrawParagraph(&c, item);
-      /* Clear the repaint flag if the whole paragraph is in the
-       * update region. */
-      if (rcUpdate->top <= ys && rcUpdate->bottom >= ye)
-        item->member.para.nFlags &= ~MEPF_REPAINT;
-    }
     item = item->member.para.next_para;
   }
   if (c.pt.y + editor->nTotalLength < c.rcView.bottom)
@@ -1263,7 +1257,8 @@ void ME_EnsureVisible(ME_TextEditor *editor, ME_Cursor *pCursor)
 void
 ME_InvalidateSelection(ME_TextEditor *editor)
 {
-  ME_DisplayItem *para1, *para2;
+  ME_DisplayItem *sel_start, *sel_end;
+  ME_DisplayItem *repaint_start = NULL, *repaint_end = NULL;
   int nStart, nEnd;
   int len = ME_GetTextLength(editor);
 
@@ -1273,32 +1268,39 @@ ME_InvalidateSelection(ME_TextEditor *editor)
   if (nStart == nEnd && editor->nLastSelStart == editor->nLastSelEnd)
     return;
   ME_WrapMarkedParagraphs(editor);
-  ME_GetSelectionParas(editor, &para1, &para2);
-  assert(para1->type == diParagraph);
-  assert(para2->type == diParagraph);
+  ME_GetSelectionParas(editor, &sel_start, &sel_end);
+  assert(sel_start->type == diParagraph);
+  assert(sel_end->type == diParagraph);
   /* last selection markers aren't always updated, which means
    * they can point past the end of the document */
   if (editor->nLastSelStart > len || editor->nLastSelEnd > len) {
-    ME_MarkForPainting(editor,
-        ME_FindItemFwd(editor->pBuffer->pFirst, diParagraph),
-        editor->pBuffer->pLast);
+    repaint_start = ME_FindItemFwd(editor->pBuffer->pFirst, diParagraph);
+    repaint_end = editor->pBuffer->pLast;
+    ME_MarkForPainting(editor, repaint_start, repaint_end);
   } else {
     /* if the start part of selection is being expanded or contracted... */
     if (nStart < editor->nLastSelStart) {
-      ME_MarkForPainting(editor, para1, editor->pLastSelStartPara->member.para.next_para);
+      repaint_start = sel_start;
+      repaint_end = editor->pLastSelStartPara->member.para.next_para;
     } else if (nStart > editor->nLastSelStart) {
-      ME_MarkForPainting(editor, editor->pLastSelStartPara, para1->member.para.next_para);
+      repaint_start = editor->pLastSelStartPara;
+      repaint_end = sel_start->member.para.next_para;
     }
+    ME_MarkForPainting(editor, repaint_start, repaint_end);
 
     /* if the end part of selection is being contracted or expanded... */
     if (nEnd < editor->nLastSelEnd) {
-      ME_MarkForPainting(editor, para2, editor->pLastSelEndPara->member.para.next_para);
+      if (!repaint_start) repaint_start = sel_end;
+      repaint_end = editor->pLastSelEndPara->member.para.next_para;
+      ME_MarkForPainting(editor, sel_end, repaint_end);
     } else if (nEnd > editor->nLastSelEnd) {
-      ME_MarkForPainting(editor, editor->pLastSelEndPara, para2->member.para.next_para);
+      if (!repaint_start) repaint_start = editor->pLastSelEndPara;
+      repaint_end = sel_end->member.para.next_para;
+      ME_MarkForPainting(editor, editor->pLastSelEndPara, repaint_end);
     }
   }
 
-  ME_InvalidateMarkedParagraphs(editor);
+  ME_InvalidateMarkedParagraphs(editor, repaint_start, repaint_end);
   /* remember the last invalidated position */
   ME_GetSelectionOfs(editor, &editor->nLastSelStart, &editor->nLastSelEnd);
   ME_GetSelectionParas(editor, &editor->pLastSelStartPara, &editor->pLastSelEndPara);

dlls/riched20/wrap.c

@@ -583,12 +583,22 @@ static void ME_WrapTextParagraph(ME_Context *c, ME_DisplayItem *tp) {
   tp->member.para.nRows = wc.nRow;
 }
 
+static void ME_MarkRepaintEnd(ME_DisplayItem *para,
+                              ME_DisplayItem **repaint_start,
+                              ME_DisplayItem **repaint_end)
+{
+    if (!*repaint_start)
+      *repaint_start = para;
+    *repaint_end = para->member.para.next_para;
+    para->member.para.nFlags |= MEPF_REPAINT;
+}
+
 BOOL ME_WrapMarkedParagraphs(ME_TextEditor *editor)
 {
   ME_DisplayItem *item;
   ME_Context c;
-  BOOL bModified = FALSE;
   int totalWidth = 0;
+  ME_DisplayItem *repaint_start = NULL, *repaint_end = NULL;
 
   ME_InitContext(&c, editor, ITextHost_TxGetDC(editor->texthost));
   c.pt.x = 0;
@@ -605,9 +615,7 @@ BOOL ME_WrapMarkedParagraphs(ME_TextEditor *editor)
     ME_WrapTextParagraph(&c, item);
 
     if (bRedraw)
-      item->member.para.nFlags |= MEPF_REPAINT;
-
-    bModified = bModified | bRedraw;
+      ME_MarkRepaintEnd(item, &repaint_start, &repaint_end);
 
     if (item->member.para.nFlags & MEPF_ROWSTART)
     {
@@ -678,10 +686,10 @@ BOOL ME_WrapMarkedParagraphs(ME_TextEditor *editor)
       {
         /* The height of the cells has grown, so invalidate the bottom of
          * the cells. */
-        item->member.para.nFlags |= MEPF_REPAINT;
+        ME_MarkRepaintEnd(item, &repaint_start, &repaint_end);
         cell = ME_FindItemBack(item, diCell);
         while (cell) {
-          ME_FindItemBack(cell, diParagraph)->member.para.nFlags |= MEPF_REPAINT;
+          ME_MarkRepaintEnd(ME_FindItemBack(cell, diParagraph), &repaint_start, &repaint_end);
           cell = cell->member.cell.prev_cell;
         }
       }
@@ -729,12 +737,17 @@ BOOL ME_WrapMarkedParagraphs(ME_TextEditor *editor)
 
   ME_DestroyContext(&c);
 
-  if (bModified || editor->nTotalLength < editor->nLastTotalLength)
-    ME_InvalidateMarkedParagraphs(editor);
-  return bModified;
+  if (repaint_start || editor->nTotalLength < editor->nLastTotalLength)
+  {
+    if (!repaint_start) repaint_start = editor->pBuffer->pFirst;
+    ME_InvalidateMarkedParagraphs(editor, repaint_start, repaint_end);
+  }
+  return !!repaint_start;
 }
 
-void ME_InvalidateMarkedParagraphs(ME_TextEditor *editor)
+void ME_InvalidateMarkedParagraphs(ME_TextEditor *editor,
+                                   ME_DisplayItem *start_para,
+                                   ME_DisplayItem *end_para)
 {
   ME_Context c;
   RECT rc;
@@ -745,13 +758,11 @@ void ME_InvalidateMarkedParagraphs(ME_TextEditor *editor)
   rc = c.rcView;
   ofs = editor->vert_si.nPos;
 
-  item = editor->pBuffer->pFirst;
-  while(item != editor->pBuffer->pLast) {
+  item = start_para;
+  while(item && item != end_para) {
     if (item->member.para.nFlags & MEPF_REPAINT) {
       rc.top = c.rcView.top + item->member.para.pt.y - ofs;
-      rc.bottom = max(c.rcView.top + item->member.para.pt.y
-                      + item->member.para.nHeight - ofs,
-                      c.rcView.bottom);
+      rc.bottom = max(rc.top + item->member.para.nHeight, c.rcView.bottom);
       ITextHost_TxInvalidateRect(editor->texthost, &rc, TRUE);
       item->member.para.nFlags &= ~MEPF_REPAINT;
     }