[Emacs-diffs] Changes to emacs/src/xdisp.c

[Eli Zaretskii]

Index: emacs/src/xdisp.c
diff -c emacs/src/xdisp.c:1.727 emacs/src/xdisp.c:1.728
*** emacs/src/xdisp.c:1.727     Wed Feb 13 11:15:52 2002
--- emacs/src/xdisp.c   Sat Feb 16 07:40:51 2002
***************
*** 582,587 ****
--- 582,594 ----
  
  int automatic_hscrolling_p;
  
+ /* How close to the margin can point get before the window is scrolled
+    horizontally.  */
+ int automatic_hscroll_margin;
+ 
+ /* How much to scroll horizontally when point is inside the above margin.  */
+ Lisp_Object Vautomatic_hscroll_step;
+ 
  /* A list of symbols, one for each supported image type.  */
  
  Lisp_Object Vimage_types;
***************
*** 8017,8027 ****
       Lisp_Object window;
  {
    int hscrolled_p = 0;
!   
    while (WINDOWP (window))
      {
        struct window *w = XWINDOW (window);
!       
        if (WINDOWP (w->hchild))
        hscrolled_p |= hscroll_window_tree (w->hchild);
        else if (WINDOWP (w->vchild))
--- 8024,8055 ----
       Lisp_Object window;
  {
    int hscrolled_p = 0;
!   int hscroll_relative_p = FLOATP (Vautomatic_hscroll_step);
!   int hscroll_step_abs = 0;
!   double hscroll_step_rel = 0;
! 
!   if (hscroll_relative_p)
!     {
!       hscroll_step_rel = XFLOAT_DATA (Vautomatic_hscroll_step);
!       if (hscroll_step_rel < 0)
!       {
!         hscroll_relative_p = 0;
!         hscroll_step_abs = 0;
!       }
!     }
!   else if (INTEGERP (Vautomatic_hscroll_step))
!     {
!       hscroll_step_abs = XINT (Vautomatic_hscroll_step);
!       if (hscroll_step_abs < 0)
!       hscroll_step_abs = 0;
!     }
!   else
!     hscroll_step_abs = 0;
! 
    while (WINDOWP (window))
      {
        struct window *w = XWINDOW (window);
! 
        if (WINDOWP (w->hchild))
        hscrolled_p |= hscroll_window_tree (w->hchild);
        else if (WINDOWP (w->vchild))
***************
*** 8043,8066 ****
                      &text_area_width, &text_area_height);
  
          /* Scroll when cursor is inside this scroll margin.  */
!         /* Shouldn't we export this `5' for customization ?  -stef  */
!         hscroll_margin = 5 * CANON_X_UNIT (XFRAME (w->frame));
!         
          if ((XFASTINT (w->hscroll)
!              && w->cursor.x < hscroll_margin)
              || (cursor_row->enabled_p
                  && cursor_row->truncated_on_right_p
!                 && (w->cursor.x > text_area_width - hscroll_margin)))
            {
              struct it it;
              int hscroll;
              struct buffer *saved_current_buffer;
              int pt;
  
              /* Find point in a display of infinite width.  */
              saved_current_buffer = current_buffer;
              current_buffer = XBUFFER (w->buffer);
!             
              if (w == XWINDOW (selected_window))
                pt = BUF_PT (current_buffer);
              else
--- 8071,8095 ----
                      &text_area_width, &text_area_height);
  
          /* Scroll when cursor is inside this scroll margin.  */
!         hscroll_margin
!           = automatic_hscroll_margin * CANON_X_UNIT (XFRAME (w->frame));
! 
          if ((XFASTINT (w->hscroll)
!              && w->cursor.x <= hscroll_margin)
              || (cursor_row->enabled_p
                  && cursor_row->truncated_on_right_p
!                 && (w->cursor.x >= text_area_width - hscroll_margin)))
            {
              struct it it;
              int hscroll;
              struct buffer *saved_current_buffer;
              int pt;
+             int wanted_x;
  
              /* Find point in a display of infinite width.  */
              saved_current_buffer = current_buffer;
              current_buffer = XBUFFER (w->buffer);
! 
              if (w == XWINDOW (selected_window))
                pt = BUF_PT (current_buffer);
              else
***************
*** 8077,8085 ****
              move_it_in_display_line_to (&it, pt, -1, MOVE_TO_POS);
              current_buffer = saved_current_buffer;
  
!             /* Center cursor in window.  */
!             hscroll = (max (0, it.current_x - text_area_width / 2)
!                        / CANON_X_UNIT (it.f));
              hscroll = max (hscroll, XFASTINT (w->min_hscroll));
  
              /* Don't call Fset_window_hscroll if value hasn't
--- 8106,8138 ----
              move_it_in_display_line_to (&it, pt, -1, MOVE_TO_POS);
              current_buffer = saved_current_buffer;
  
!             /* Position cursor in window.  */
!             if (!hscroll_relative_p && hscroll_step_abs == 0)
!               hscroll = max (0, it.current_x - text_area_width / 2)
!                         / CANON_X_UNIT (it.f);
!             else if (w->cursor.x >= text_area_width - hscroll_margin)
!               {
!                 if (hscroll_relative_p)
!                   wanted_x = text_area_width * (1 - hscroll_step_rel)
!                              - hscroll_margin;
!                 else
!                   wanted_x = text_area_width
!                              - hscroll_step_abs * CANON_X_UNIT (it.f)
!                              - hscroll_margin;
!                 hscroll
!                   = max (0, it.current_x - wanted_x) / CANON_X_UNIT (it.f);
!               }
!             else
!               {
!                 if (hscroll_relative_p)
!                   wanted_x = text_area_width * hscroll_step_rel
!                              + hscroll_margin;
!                 else
!                   wanted_x = hscroll_step_abs * CANON_X_UNIT (it.f)
!                              + hscroll_margin;
!                 hscroll
!                   = max (0, it.current_x - wanted_x) / CANON_X_UNIT (it.f);
!               }
              hscroll = max (hscroll, XFASTINT (w->min_hscroll));
  
              /* Don't call Fset_window_hscroll if value hasn't
***************
*** 15010,15015 ****
--- 15063,15091 ----
    DEFVAR_BOOL ("automatic-hscrolling", &automatic_hscrolling_p,
      doc: /* *Non-nil means scroll the display automatically to make point 
visible.  */);
    automatic_hscrolling_p = 1;
+ 
+   DEFVAR_INT ("automatic-hscroll-margin", &automatic_hscroll_margin,
+     doc: /* *How many columns away from the window edge point is allowed to 
get
+ before automatic hscrolling will horizontally scroll the window.  */);
+   automatic_hscroll_margin = 5;
+ 
+   DEFVAR_LISP ("automatic-hscroll-step", &Vautomatic_hscroll_step,
+     doc: /* *How many columns to scroll the window when point gets too close 
to the edge.
+ When point is less than `automatic-hscroll-margin' columns from the window
+ edge, automatic hscrolling will scroll the window by the amount of columns
+ determined by this variable.  If its value is a positive integer, scroll that
+ many columns.  If it's a positive floating-point number, it specifies the
+ fraction of the window's width to scroll.  If it's nil or zero, point will be
+ centered horizontally after the scroll.  Any other value, including negative
+ numbers, are treated as if the value were zero.
+ 
+ Automatic hscrolling always moves point outside the scroll margin, so if
+ point was more than scroll step columns inside the margin, the window will
+ scroll more than the value given by the scroll step.
+ 
+ Note that the lower bound for automatic hscrolling specified by `scroll-left'
+ and `scroll-right' overrides this variable's effect.  */);
+   Vautomatic_hscroll_step = make_number (0);
    
    DEFVAR_LISP ("image-types", &Vimage_types,
      doc: /* List of supported image types.