add a clarifying comment about threading/GUI for normalization

diff --git a/gtk2_ardour/normalize_dialog.cc b/gtk2_ardour/normalize_dialog.cc
index 9872bcbc35223fe8fd8526fdd89d5ef76f439b97..308328538cac2cf18ed654efe4258109c0f47bf4 100644 (file)
--- a/gtk2_ardour/normalize_dialog.cc
+++ b/gtk2_ardour/normalize_dialog.cc
@@ -95,6 +95,10 @@ NormalizeDialog::target () const
 void
 NormalizeDialog::update_progress_gui (float p)
 {
+       /* Normalization is run inside the GUI thread, so we can directly
+        * update the progress bar when notified about progress.
+        */
+
        _progress_bar->set_fraction (p);
 }