This commit was generated by cvs2svn to compensate for changes in r4969,

[chise/xemacs-chise.git.1] / src / scrollbar-msw.c

diff --git a/src/scrollbar-msw.c b/src/scrollbar-msw.c
index 20eeb9c..832fcbd 100644 (file)
--- a/src/scrollbar-msw.c
+++ b/src/scrollbar-msw.c
@@ -47,14 +47,14 @@ mswindows_create_scrollbar_instance (struct frame *f, int vertical,
                                     struct scrollbar_instance *sb)
 {
   int orientation;
-  
+
   sb->scrollbar_data = xnew_and_zero (struct mswindows_scrollbar_data);
-  
+
   if (vertical)
     orientation = SBS_VERT;
   else
     orientation = SBS_HORZ;
-  
+
   SCROLLBAR_MSW_HANDLE (sb) =
     CreateWindowEx(0, "SCROLLBAR", 0, orientation|WS_CHILD,
                 CW_USEDEFAULT, CW_USEDEFAULT,
@@ -83,7 +83,7 @@ static void
 mswindows_free_scrollbar_instance (struct scrollbar_instance *sb)
 {
   DestroyWindow (SCROLLBAR_MSW_HANDLE (sb));
-  if (sb->scrollbar_data) 
+  if (sb->scrollbar_data)
     xfree (sb->scrollbar_data);
 }
 
@@ -146,7 +146,7 @@ mswindows_update_scrollbar_instance_values (struct window *w,
   UPDATE_POS_FIELD (scrollbar_width);
   UPDATE_POS_FIELD (scrollbar_height);
 
-  if (pos_changed) 
+  if (pos_changed)
     {
       MoveWindow(SCROLLBAR_MSW_HANDLE (sb),
                 new_scrollbar_x, new_scrollbar_y,
@@ -186,7 +186,7 @@ mswindows_handle_scrollbar_event (HWND hwnd, int code, int pos)
   f = XFRAME (frame);
 
   /* SB_LINEDOWN == SB_CHARLEFT etc. This is the way they will
-     always be - any Windows is binary compatible backward with 
+     always be - any Windows is binary compatible backward with
      old programs */
 
   switch (code)
@@ -195,12 +195,12 @@ mswindows_handle_scrollbar_event (HWND hwnd, int code, int pos)
       mswindows_enqueue_misc_user_event
        (frame, vert ? Qscrollbar_line_down : Qscrollbar_char_right, win);
       break;
-         
+
     case SB_LINEUP:
       mswindows_enqueue_misc_user_event
        (frame, vert ? Qscrollbar_line_up : Qscrollbar_char_left, win);
       break;
-         
+
     case SB_PAGEDOWN:
       mswindows_enqueue_misc_user_event
        (win, vert ? Qscrollbar_page_down : Qscrollbar_page_right,
@@ -213,7 +213,7 @@ mswindows_handle_scrollbar_event (HWND hwnd, int code, int pos)
         vert ? Qscrollbar_page_up : Qscrollbar_page_left,
         vert ? Fcons (win, Qnil) : win);
       break;
-         
+
     case SB_BOTTOM:
       mswindows_enqueue_misc_user_event
        (frame, vert ? Qscrollbar_to_bottom : Qscrollbar_to_right, win);
@@ -265,6 +265,69 @@ mswindows_handle_scrollbar_event (HWND hwnd, int code, int pos)
     }
 }
 
+static int
+can_scroll(struct scrollbar_instance* scrollbar)
+{
+  return scrollbar != NULL
+       && IsWindowVisible (SCROLLBAR_MSW_HANDLE (scrollbar))
+       && IsWindowEnabled (SCROLLBAR_MSW_HANDLE (scrollbar));
+}
+
+int
+mswindows_handle_mousewheel_event (Lisp_Object frame, int keys, int delta)
+{
+  int hasVertBar, hasHorzBar;  /* Indicates presence of scroll bars */
+  unsigned wheelScrollLines = 0; /* Number of lines per wheel notch */
+
+  /* Find the currently selected window */
+  Lisp_Object win = FRAME_SELECTED_WINDOW (XFRAME (frame));
+  struct window* w = XWINDOW (win);
+  struct window_mirror* mirror = find_window_mirror (w);
+
+  /* Check that there is something to scroll */
+  hasVertBar = can_scroll (mirror->scrollbar_vertical_instance);
+  hasHorzBar = can_scroll (mirror->scrollbar_horizontal_instance);
+  if (!hasVertBar && !hasHorzBar)
+    return FALSE;
+
+  /* No support for panning and zooming, so ignore */
+  if (keys & (MK_SHIFT | MK_CONTROL))
+    return FALSE;
+
+  /* Get the number of lines per wheel delta */
+  SystemParametersInfo (SPI_GETWHEELSCROLLLINES, 0, &wheelScrollLines, 0);
+
+  /* Calculate the amount to scroll */
+  if (wheelScrollLines == WHEEL_PAGESCROLL)
+    {
+      /* Scroll by a page */
+      Lisp_Object function;
+      if (hasVertBar)
+       function = delta > 0 ? Qscrollbar_page_up : Qscrollbar_page_down;
+      else
+       function = delta > 0 ? Qscrollbar_page_left : Qscrollbar_page_right;
+      mswindows_enqueue_misc_user_event (frame, function, Fcons (win, Qnil));
+    }
+  else /* Scroll by a number of lines */
+    {
+      /* Calc the number of lines to scroll */
+      int toScroll = MulDiv (delta, wheelScrollLines, WHEEL_DELTA);
+
+      /* Do the scroll */
+      Lisp_Object function;
+      if (hasVertBar)
+       function = delta > 0 ? Qscrollbar_line_up : Qscrollbar_line_down;
+      else
+       function = delta > 0 ? Qscrollbar_char_left : Qscrollbar_char_right;
+      if (toScroll < 0)
+       toScroll = -toScroll;
+      while (toScroll--)
+       mswindows_enqueue_misc_user_event (frame, function, win);
+    }
+
+  return TRUE;
+}
+
 #ifdef MEMORY_USAGE_STATS
 
 static int