treeview: if we are below rows that changed height: redraw

We have to redraw if we are below a couple of rows that changed height
in do_validate_rows().  This will still require a redraw for a large
amount of cases, can we do better?  You would expect that a redraw of
the tree view is not required when the dy changes with the same delta
as the delta of the height accrued when validating the nodes.  This
further optimization will likely require changes to the top_row/dy
synchronization code.

diff --git a/gtk/gtktreeview.c b/gtk/gtktreeview.c
index ed45e3bafac3bb9b0a9e6fa82c7dbd219cb51410..4c62fa64dd486a1cffbbac628435ae219594d094 100644 (file)
--- a/gtk/gtktreeview.c
+++ b/gtk/gtktreeview.c
@@ -6631,6 +6631,7 @@ do_validate_rows (GtkTreeView *tree_view, gboolean queue_resize)
   GTimer *timer;
   gint i = 0;
 
+  gint y = -1;
   gint prev_height = -1;
   gboolean fixed_height = TRUE;
 
@@ -6652,6 +6653,8 @@ do_validate_rows (GtkTreeView *tree_view, gboolean queue_resize)
 
   do
     {
+      gboolean changed = FALSE;
+
       if (! GTK_RBNODE_FLAG_SET (tree_view->priv->tree->root, GTK_RBNODE_DESCENDANTS_INVALID))
        {
          retval = FALSE;
@@ -6711,8 +6714,16 @@ do_validate_rows (GtkTreeView *tree_view, gboolean queue_resize)
          gtk_tree_model_get_iter (tree_view->priv->model, &iter, path);
        }
 
-      validated_area = validate_row (tree_view, tree, node, &iter, path) ||
-                       validated_area;
+      changed = validate_row (tree_view, tree, node, &iter, path);
+      validated_area = changed || validated_area;
+
+      if (changed)
+        {
+          gint offset = gtk_tree_view_get_row_y_offset (tree_view, tree, node);
+
+          if (y == -1 || y > offset)
+            y = offset;
+        }
 
       if (!tree_view->priv->fixed_height_check)
         {
@@ -6758,6 +6769,12 @@ do_validate_rows (GtkTreeView *tree_view, gboolean queue_resize)
        */
       gtk_tree_view_size_request (GTK_WIDGET (tree_view), &requisition, FALSE);
 
+      /* If rows above the current position have changed height, this has
+       * affected the current view and thus needs a redraw.
+       */
+      if (y != -1 && y < gtk_adjustment_get_value (tree_view->priv->vadjustment))
+        gtk_widget_queue_draw (GTK_WIDGET (tree_view));
+
       gtk_adjustment_set_upper (tree_view->priv->hadjustment,
                                 MAX (gtk_adjustment_get_upper (tree_view->priv->hadjustment), requisition.width));
       gtk_adjustment_set_upper (tree_view->priv->vadjustment,