Support bidi-reordered text in mouse-highlighted mode- and header-lines.

Note: Not tested with actually bidi-reordered strings.

 xdisp.c (note_mode_line_or_margin_highlight): Support
 bidi-reordered strings and R2L glyph rows.  Fix more comments.

diff --git a/src/ChangeLog b/src/ChangeLog
index 0f7d39e..5f6fed1 100644 (file)
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2010-10-16  Eli Zaretskii  <eliz@gnu.org>
+
+       * xdisp.c (note_mode_line_or_margin_highlight): Support
+       bidi-reordered strings and R2L glyph rows.  Fix more comments.
+
 2010-10-16  Eli Zaretskii  <eliz@gnu.org>
 
        * xdisp.c (rows_from_pos_range, mouse_face_from_buffer_pos)

diff --git a/src/xdisp.c b/src/xdisp.c
index 4a7cc27..41be01c 100644 (file)
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -24602,6 +24602,8 @@ note_mode_line_or_margin_highlight (Lisp_Object window, int x, int y,
       int x0;
       struct glyph *end;
 
+      /* Kludge alert: mode_line_string takes X/Y in pixels, but
+        returns them in row/column units!  */
       string = mode_line_string (w, area, &x, &y, &charpos,
                                 &object, &dx, &dy, &width, &height);
 
@@ -24627,6 +24629,8 @@ note_mode_line_or_margin_highlight (Lisp_Object window, int x, int y,
   else
     {
       x -= WINDOW_LEFT_SCROLL_BAR_AREA_WIDTH (w);
+      /* Kludge alert: marginal_area_string takes X/Y in pixels, but
+        returns them in row/column units!  */
       string = marginal_area_string (w, area, &x, &y, &charpos,
                                     &object, &dx, &dy, &width, &height);
     }
@@ -24715,21 +24719,26 @@ note_mode_line_or_margin_highlight (Lisp_Object window, int x, int y,
          int gpos;
          int gseq_length;
          int total_pixel_width;
-         EMACS_INT ignore;
+         EMACS_INT begpos, endpos, ignore;
 
          int vpos, hpos;
 
          b = Fprevious_single_property_change (make_number (charpos + 1),
                                                Qmouse_face, string, Qnil);
          if (NILP (b))
-           b = make_number (0);
+           begpos = 0;
+         else
+           begpos = XINT (b);
 
          e = Fnext_single_property_change (pos, Qmouse_face, string, Qnil);
          if (NILP (e))
-           e = make_number (SCHARS (string));
+           endpos = SCHARS (string);
+         else
+           endpos = XINT (e);
 
          /* Calculate the glyph position GPOS of GLYPH in the
-            displayed string.
+            displayed string, relative to the beginning of the
+            highlighted part of the string.
 
             Note: GPOS is different from CHARPOS.  CHARPOS is the
             position of GLYPH in the internal string object.  A mode
@@ -24737,71 +24746,89 @@ note_mode_line_or_margin_highlight (Lisp_Object window, int x, int y,
             a flattened string by the Emacs Lisp interpreter.  The
             internal string is an element of those structures.  The
             displayed string is the flattened string.  */
-         gpos = 0;
-         if (glyph > row_start_glyph)
-           {
-             tmp_glyph = glyph - 1;
-             while (tmp_glyph >= row_start_glyph
-                    && tmp_glyph->charpos >= XINT (b)
-                    && EQ (tmp_glyph->object, glyph->object))
-               {
-                 tmp_glyph--;
-                 gpos++;
-               }
-           }
-
-         /* Calculate the glyph sequence length GSEQ_LENGTH of the
-            displayed string to which GLYPH belongs.  Note:
-            GSEQ_LENGTH is different from SCHARS (STRING), because
-            the latter returns the length of the internal string.  */
-         for (tmp_glyph = glyph, gseq_length = gpos;
-              tmp_glyph->charpos < XINT (e);
-              tmp_glyph++, gseq_length++)
-             {
-               if (!EQ (tmp_glyph->object, glyph->object))
-                 break;
-             }
+         tmp_glyph = row_start_glyph;
+         while (tmp_glyph < glyph
+                && (!(EQ (tmp_glyph->object, glyph->object)
+                      && begpos <= tmp_glyph->charpos
+                      && tmp_glyph->charpos < endpos)))
+           tmp_glyph++;
+         gpos = glyph - tmp_glyph;
+
+         /* Calculate the length GSEQ_LENGTH of the glyph sequence of
+            the highlighted part of the displayed string to which
+            GLYPH belongs.  Note: GSEQ_LENGTH is different from
+            SCHARS (STRING), because the latter returns the length of
+            the internal string.  */
+         for (tmp_glyph = row->glyphs[TEXT_AREA] + row->used[TEXT_AREA] - 1;
+              tmp_glyph > glyph
+                && (!(EQ (tmp_glyph->object, glyph->object)
+                      && begpos <= tmp_glyph->charpos
+                      && tmp_glyph->charpos < endpos));
+              tmp_glyph--)
+           ;
+         gseq_length = gpos + (tmp_glyph - glyph) + 1;
 
+         /* Calculate the total pixel width of all the glyphs between
+            the beginning of the highlighted area and GLYPH.  */
          total_pixel_width = 0;
          for (tmp_glyph = glyph - gpos; tmp_glyph != glyph; tmp_glyph++)
            total_pixel_width += tmp_glyph->pixel_width;
 
-         /* Pre calculation of re-rendering position.  */
+         /* Pre calculation of re-rendering position.  Note: X is in
+            column units here, after the call to mode_line_string or
+            marginal_area_string.  */
          hpos = x - gpos;
          vpos = (area == ON_MODE_LINE
                  ? (w->current_matrix)->nrows - 1
                  : 0);
 
-         /* If the re-rendering position is included in the last
-            re-rendering area, we should do nothing.  */
+         /* If GLYPH's position is included in the region that is
+            already drawn in mouse face, we have nothing to do.  */
          if ( EQ (window, dpyinfo->mouse_face_window)
-              && dpyinfo->mouse_face_beg_col <= hpos
-              && hpos < dpyinfo->mouse_face_end_col
+              && (!row->reversed_p
+                  ? (dpyinfo->mouse_face_beg_col <= hpos
+                     && hpos < dpyinfo->mouse_face_end_col)
+                  /* In R2L rows we swap BEG and END, see below.  */
+                  : (dpyinfo->mouse_face_end_col <= hpos
+                     && hpos < dpyinfo->mouse_face_beg_col))
               && dpyinfo->mouse_face_beg_row == vpos )
            return;
 
          if (clear_mouse_face (dpyinfo))
            cursor = No_Cursor;
 
-         dpyinfo->mouse_face_beg_col = hpos;
-         dpyinfo->mouse_face_beg_row = vpos;
-
-         dpyinfo->mouse_face_beg_x   = original_x_pixel - (total_pixel_width + dx);
-         dpyinfo->mouse_face_beg_y   = 0;
-
-         dpyinfo->mouse_face_end_col = hpos + gseq_length;
-         dpyinfo->mouse_face_end_row = dpyinfo->mouse_face_beg_row;
-
-         dpyinfo->mouse_face_end_x   = 0;
-         dpyinfo->mouse_face_end_y   = 0;
+         if (!row->reversed_p)
+           {
+             dpyinfo->mouse_face_beg_col = hpos;
+             dpyinfo->mouse_face_beg_x   = original_x_pixel
+                                           - (total_pixel_width + dx);
+             dpyinfo->mouse_face_end_col = hpos + gseq_length;
+             dpyinfo->mouse_face_end_x   = 0;
+           }
+         else
+           {
+             /* In R2L rows, show_mouse_face expects BEG and END
+                coordinates to be swapped.  */
+             dpyinfo->mouse_face_end_col = hpos;
+             dpyinfo->mouse_face_end_x   = original_x_pixel
+                                           - (total_pixel_width + dx);
+             dpyinfo->mouse_face_beg_col = hpos + gseq_length;
+             dpyinfo->mouse_face_beg_x   = 0;
+           }
 
+         dpyinfo->mouse_face_beg_row  = vpos;
+         dpyinfo->mouse_face_end_row  = dpyinfo->mouse_face_beg_row;
+         dpyinfo->mouse_face_beg_y    = 0;
+         dpyinfo->mouse_face_end_y    = 0;
          dpyinfo->mouse_face_past_end = 0;
-         dpyinfo->mouse_face_window  = window;
+         dpyinfo->mouse_face_window   = window;
 
          dpyinfo->mouse_face_face_id = face_at_string_position (w, string,
                                                                 charpos,
-                                                                0, 0, 0, &ignore,
-                                                                glyph->face_id, 1);
+                                                                0, 0, 0,
+                                                                &ignore,
+                                                                glyph->face_id,
+                                                                1);
          show_mouse_face (dpyinfo, DRAW_MOUSE_FACE);
 
          if (NILP (pointer))