handle enter/leave items when zooming and scrolling occur

gtk2_ardour/editor.cc

@@ -4269,7 +4269,16 @@ Editor::set_samples_per_pixel (framecnt_t spp)
 
 	ZoomChanged (); /* EMIT_SIGNAL */
 
-	//reset_scrolling_region ();
+	ArdourCanvas::GtkCanvasViewport* c;
+
+	c = get_time_bars_canvas();
+	if (c) {
+		c->canvas()->zoomed ();
+	}
+	c = get_track_canvas();
+	if (c) {
+		c->canvas()->zoomed ();
+	}
 
 	if (playhead_cursor) {
 		playhead_cursor->set_position (playhead_cursor->current_frame ());

gtk2_ardour/editor_routes.cc

@@ -1004,12 +1004,6 @@ EditorRoutes::hide_all_tracks (bool /*with_select*/)
 	}
 
 	resume_redisplay ();
-
-	/* XXX this seems like a hack and half, but its not clear where to put this
-	   otherwise.
-	*/
-
-	//reset_scrolling_region ();
 }
 
 void

libs/canvas/canvas.cc

@@ -49,6 +49,14 @@ Canvas::scroll_to (Coord x, Coord y)
 {
 	_scroll_offset_x = x;
 	_scroll_offset_y = y;
+
+	enter_leave_items (0); // no current mouse position 
+}
+
+void
+Canvas::zoomed ()
+{
+	enter_leave_items (0); // no current mouse position
 }
 
 /** Render an area of the canvas.

libs/canvas/canvas/canvas.h

@@ -107,6 +107,8 @@ public:
         void scroll_to (Coord x, Coord y);
         virtual Rect visible_area () const = 0;
 
+        void zoomed();
+    
         std::string indent() const;
         std::string render_indent() const;
         void dump (std::ostream&) const;