[PATH] textDrag.c: BlockDragSelection(): use cursorToHint to reduce redrawing

[Bert Wesarg]

We have a way to optimize redrawing any cursor movement when we change the text
buffer. This patch apply it to the BlockDragSelection() function.

Actually this fixes a drawing bug with the Colored Cursorline (SF#683567) patch.
The cursor line is drawn above the selection while scrolling with the section
down and leaves un-erased cursor lines behind.

Regards
Bert

---

 source/textDrag.c |   20 +++++++++++++++-----
 1 files changed, 15 insertions(+), 5 deletions(-)

diff --quilt old/source/textDrag.c new/source/textDrag.c
--- old/source/textDrag.c
+++ new/source/textDrag.c
@@ -361,12 +361,25 @@ void BlockDragSelection(TextWidget tw, i
  
     /* Make the changes in the real buffer */
     repText = BufGetRange(tempBuf, modRangeStart - tempStart,
     	    tempModRangeEnd - tempStart);
     BufFree(tempBuf);
+
     TextDBlankCursor(textD);
+
+    /* set cursorToHint to new cursor position to optimize redrawing */
+    if (rectangular || overlay) {
+        insRectEnd = insRectStart + origSel->rectEnd - origSel->rectStart;
+        textD->cursorToHint = BufCountForwardDispChars(buf,
+                BufCountForwardNLines(buf, insStart, tw->text.dragNLines),
+                insRectEnd);
+    } else {
+        textD->cursorToHint = insStart + origSel->end - origSel->start;
+    }
+
     BufReplace(buf, modRangeStart, bufModRangeEnd, repText);
+    textD->cursorToHint = NO_HINT;
     XtFree(repText);
     
     /* Store the necessary information for undoing this step */
     tw->text.dragInsertPos = insStart;
     tw->text.dragRectStart = insRectStart;
@@ -375,22 +388,19 @@ void BlockDragSelection(TextWidget tw, i
     tw->text.dragSourceDeletePos = sourceDeletePos;
     tw->text.dragSourceInserted = sourceInserted;
     tw->text.dragSourceDeleted = sourceDeleted;
     tw->text.dragType = dragType;
  
-    /* Reset the selection and cursor position */
+    /* Reset the selection */
     if (rectangular || overlay) {
     	insRectEnd = insRectStart + origSel->rectEnd - origSel->rectStart;
     	BufRectSelect(buf, insStart, insStart + insertInserted, insRectStart,
     	    	insRectEnd);
-    	TextDSetInsertPosition(textD, BufCountForwardDispChars(buf,
-    	    	BufCountForwardNLines(buf, insStart, tw->text.dragNLines),
-    	    	insRectEnd));
     } else {
     	BufSelect(buf, insStart, insStart + origSel->end - origSel->start);
-    	TextDSetInsertPosition(textD, insStart + origSel->end - origSel->start);
     }
+
     TextDUnblankCursor(textD);
     XtCallCallbacks((Widget)tw, textNcursorMovementCallback, (XtPointer)NULL);
     tw->text.emTabsBeforeCursor = 0;
 }