range: Avoid animations during slider drag

If the drag gesture gets a GtkGesture::updated signal, the user
is directly interacting through pointer/touch with the range slider,
animating the adjustment value change in this situation can produce
perceived lag, so set the value immediately when this is happening.

gtk/gtkadjustment.c

@@ -428,6 +428,17 @@ gtk_adjustment_get_value (GtkAdjustment *adjustment)
   return adjustment->priv->value;
 }
 
+gdouble
+gtk_adjustment_get_target_value (GtkAdjustment *adjustment)
+{
+  g_return_val_if_fail (GTK_IS_ADJUSTMENT (adjustment), 0.0);
+
+  if (adjustment->priv->tick_id)
+    return adjustment->priv->target;
+  else
+    return adjustment->priv->value;
+}
+
 static void
 adjustment_set_value (GtkAdjustment *adjustment,
                       gdouble        value)

gtk/gtkadjustmentprivate.h

@@ -29,6 +29,7 @@ void gtk_adjustment_enable_animation (GtkAdjustment *adjustment,
                                       guint          duration);
 void gtk_adjustment_animate_to_value (GtkAdjustment *adjustment,
                                       gdouble        value);
+gdouble gtk_adjustment_get_target_value (GtkAdjustment *adjustment);
 
 G_END_DECLS
 

gtk/gtkrange.c

@@ -156,6 +156,9 @@ struct _GtkRangePrivate
   /* Fill level */
   guint show_fill_level        : 1;
   guint restrict_to_fill_level : 1;
+
+  /* Whether dragging is ongoing */
+  guint in_drag                : 1;
 };
 
 
@@ -2909,6 +2912,7 @@ gtk_range_drag_gesture_update (GtkGestureDrag *gesture,
   gtk_gesture_drag_get_start_point (gesture, &start_x, &start_y);
   priv->mouse_x = start_x + offset_x;
   priv->mouse_y = start_y + offset_y;
+  priv->in_drag = TRUE;
 
   update_autoscroll_mode (range);
 
@@ -2922,6 +2926,7 @@ gtk_range_drag_gesture_end (GtkGestureDrag       *gesture,
                             gdouble               offset_y,
                             GtkRange             *range)
 {
+  range->priv->in_drag = FALSE;
   stop_scrolling (range);
 }
 
@@ -3997,7 +4002,11 @@ gtk_range_real_change_value (GtkRange      *range,
       priv->need_recalc = TRUE;
 
       gtk_widget_queue_draw (GTK_WIDGET (range));
-      gtk_adjustment_animate_to_value (priv->adjustment, value);
+
+      if (priv->in_drag)
+        gtk_adjustment_set_value (priv->adjustment, value);
+      else
+        gtk_adjustment_animate_to_value (priv->adjustment, value);
     }
 
   return FALSE;

gtk/gtktextview.c

@@ -2163,8 +2163,8 @@ gtk_text_view_scroll_to_iter (GtkTextView   *text_view,
   
   if (scroll_inc != 0)
     {
-      gtk_adjustment_set_value (text_view->priv->vadjustment,
+      gtk_adjustment_animate_to_value (text_view->priv->vadjustment,
-                                current_y_scroll + scroll_inc);
+				       current_y_scroll + scroll_inc);
 
       DV (g_print (" vert increment %d\n", scroll_inc));
     }
@@ -2200,8 +2200,8 @@ gtk_text_view_scroll_to_iter (GtkTextView   *text_view,
   
   if (scroll_inc != 0)
     {
-      gtk_adjustment_set_value (text_view->priv->hadjustment,
+      gtk_adjustment_animate_to_value (text_view->priv->hadjustment,
-                                current_x_scroll + scroll_inc);
+				       current_x_scroll + scroll_inc);
 
       DV (g_print (" horiz increment %d\n", scroll_inc));
     }
@@ -5858,10 +5858,11 @@ gtk_text_view_move_cursor (GtkTextView     *text_view,
           break;
 	}
 
-      old_xpos = priv->xoffset;
+      old_xpos = gtk_adjustment_get_value (priv->hadjustment);
-      old_ypos = priv->yoffset;
+      old_ypos = gtk_adjustment_get_value (priv->vadjustment);
       gtk_text_view_move_viewport (text_view, scroll_step, count);
-      if ((old_xpos == priv->xoffset && old_ypos == priv->yoffset) &&
+      if ((old_xpos == gtk_adjustment_get_target_value (priv->hadjustment) &&
+           old_ypos == gtk_adjustment_get_target_value (priv->vadjustment)) &&
           leave_direction != -1 &&
           !gtk_widget_keynav_failed (GTK_WIDGET (text_view),
                                      leave_direction))
@@ -6182,16 +6183,14 @@ gtk_text_view_scroll_pages (GtkTextView *text_view,
     {
       gtk_text_view_get_virtual_cursor_pos (text_view, NULL, &cursor_x_pos, &cursor_y_pos);
 
-      oldval = gtk_adjustment_get_value (adjustment);
+      oldval = newval = gtk_adjustment_get_target_value (adjustment);
-      newval = gtk_adjustment_get_value (adjustment);
-
       newval += count * gtk_adjustment_get_page_increment (adjustment);
 
       gtk_adjustment_animate_to_value (adjustment, newval);
-      cursor_y_pos += gtk_adjustment_get_value (adjustment) - oldval;
+      cursor_y_pos += newval - oldval;
 
       gtk_text_layout_get_iter_at_pixel (priv->layout, &new_insert, cursor_x_pos, cursor_y_pos);
-      clamp_iter_onscreen (text_view, &new_insert);
+
       move_cursor (text_view, &new_insert, extend_selection);
 
       gtk_text_view_set_virtual_cursor_pos (text_view, cursor_x_pos, cursor_y_pos);
@@ -6201,7 +6200,6 @@ gtk_text_view_scroll_pages (GtkTextView *text_view,
    * only guarantees 1 pixel onscreen.
    */
   DV(g_print (G_STRLOC": scrolling onscreen\n"));
-  gtk_text_view_scroll_mark_onscreen (text_view, insert_mark);
 
   return !gtk_text_iter_equal (&old_insert, &new_insert);
 }
@@ -6266,16 +6264,13 @@ gtk_text_view_scroll_hpages (GtkTextView *text_view,
     {
       gtk_text_view_get_virtual_cursor_pos (text_view, NULL, &cursor_x_pos, &cursor_y_pos);
 
-      oldval = gtk_adjustment_get_value (adjustment);
+      oldval = newval = gtk_adjustment_get_target_value (adjustment);
-      newval = gtk_adjustment_get_value (adjustment);
-
       newval += count * gtk_adjustment_get_page_increment (adjustment);
 
       gtk_adjustment_animate_to_value (adjustment, newval);
-      cursor_x_pos += gtk_adjustment_get_value (adjustment) - oldval;
+      cursor_x_pos += newval - oldval;
 
       gtk_text_layout_get_iter_at_pixel (priv->layout, &new_insert, cursor_x_pos, cursor_y_pos);
-      clamp_iter_onscreen (text_view, &new_insert);
       move_cursor (text_view, &new_insert, extend_selection);
 
       gtk_text_view_set_virtual_cursor_pos (text_view, cursor_x_pos, cursor_y_pos);
@@ -6291,7 +6286,6 @@ gtk_text_view_scroll_hpages (GtkTextView *text_view,
    * only guarantees 1 pixel onscreen.
    */
   DV(g_print (G_STRLOC": scrolling onscreen\n"));
-  gtk_text_view_scroll_mark_onscreen (text_view, insert_mark);
 
   return !gtk_text_iter_equal (&old_insert, &new_insert);
 }