(display_text_line): Always store in charstart

even if at endp.  When clearing charstart, do the whole width.

(redisplay): Call verify_charstarts.

(redisplay): Don't call adjust_window_charstarts
if on last text line of window.

diff --git a/src/xdisp.c b/src/xdisp.c
index 65340f5..93ca88b 100644 (file)
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -623,23 +623,26 @@ redisplay ()
          if (cursor_vpos >= 0 && this_line_bufpos
              && this_line_endpos == tlendpos)
            {
-             int left = XFASTINT (w->left);
-             int *charstart_next_line
-               = FRAME_CURRENT_GLYPHS (XFRAME (WINDOW_FRAME (w)))->charstarts[this_line_vpos + 1];
-             int i;
-             int adjust;
-
-             if (Z - tlendpos == ZV)
-               /* This line ends at end of (accessible part of) buffer.
-                  There is no newline to count.  */
-               adjust = Z - tlendpos - charstart_next_line[left];
-             else
-               /* This line ends in a newline.
-                  Must take account of the newline and the rest of the
-                  text that follows.  */
-               adjust = Z - tlendpos + 1 - charstart_next_line[left];
-
-             adjust_window_charstarts (w, this_line_vpos, adjust);
+             if (this_line_vpos < XFASTINT (w->top) + window_internal_height (w))
+               {
+                 int left = XFASTINT (w->left);
+                 int *charstart_next_line
+                   = FRAME_CURRENT_GLYPHS (XFRAME (WINDOW_FRAME (w)))->charstarts[this_line_vpos + 1];
+                 int i;
+                 int adjust;
+
+                 if (Z - tlendpos == ZV)
+                   /* This line ends at end of (accessible part of) buffer.
+                      There is no newline to count.  */
+                   adjust = Z - tlendpos - charstart_next_line[left];
+                 else
+                   /* This line ends in a newline.
+                      Must take account of the newline and the rest of the
+                      text that follows.  */
+                   adjust = Z - tlendpos + 1 - charstart_next_line[left];
+
+                 adjust_window_charstarts (w, this_line_vpos, adjust);
+               }
 
              if (XFASTINT (w->width) != FRAME_WIDTH (XFRAME (WINDOW_FRAME (w))))
                preserve_other_columns (w);
@@ -829,6 +832,7 @@ update:
          w->window_end_valid = Qt;
          last_arrow_position = Voverlay_arrow_position;
          last_arrow_string = Voverlay_arrow_string;
+         verify_charstarts (w);
          if (frame_up_to_date_hook != 0)
            (*frame_up_to_date_hook) (selected_frame);
        }
@@ -2071,12 +2075,15 @@ display_text_line (w, start, vpos, hpos, taboffset)
 #ifdef USE_TEXT_PROPERTIES
   next_invisible = pos;
 #endif
-  while (p1 < endp)
+  while (1)
     {
       /* Record which glyph starts a character,
         and the character position of that character.  */
       charstart[p1 - p1start] = pos;
 
+      if (p1 >= endp)
+       break;
+
       p1prev = p1;
       if (pos >= pause)
        {
@@ -2287,7 +2294,10 @@ display_text_line (w, start, vpos, hpos, taboffset)
   /* Store 0 in this charstart line for the positions where
      there is no character.  But do leave what was recorded
      for the character that ended the line.  */
-  for (i = p1 - p1start + 1; i < endp - p1start; i++)
+  /* Add 1 in the endtest to compensate for the fact that ENDP was
+     made from WIDTH, which is 1 less than the window's actual
+     internal width.  */
+  for (i = p1 - p1start + 1; i < endp - p1start + 1; i++)
     charstart[i] = 0;
 
   /* Handle continuation in middle of a character */