Prepare screenshot of all mixer-strips

This will allow to create a PNG of all mixer-strips, even those currently
off-screen due to scrolling. It currently shows the main scroll-pane
page only (master-bus, VCAs are not included).

This method is not yet exposed.

1 files changed, 20 insertions, 0 deletions

diff --git a/gtk2_ardour/mixer_ui.cc b/gtk2_ardour/mixer_ui.cc
index 4bf6d60f7b..1773c4497c 100644
--- a/gtk2_ardour/mixer_ui.cc
+++ b/gtk2_ardour/mixer_ui.cc
@@ -30,6 +30,7 @@
 #include <glibmm/threads.h>
 
 #include <gtkmm/accelmap.h>
+#include <gtkmm/offscreenwindow.h>
 #include <gtkmm/stock.h>
 
 #include "pbd/convert.h"
@@ -3501,3 +3502,22 @@ Mixer_UI::vca_unassign (boost::shared_ptr<VCA> vca)
 		}
 	}
 }
+
+void
+Mixer_UI::screenshot (std::string const& filename)
+{
+	Gtk::OffscreenWindow osw;
+	int height = strip_packer.get_height();
+	strip_group_box.remove (strip_packer);
+	osw.add (strip_packer);
+	add_button.hide ();
+	osw.set_size_request (-1, height);
+	osw.show();
+	osw.get_window()->process_updates (true);
+	Glib::RefPtr<Gdk::Pixbuf> pb = osw.get_pixbuf ();
+	pb->save (filename, "png");
+	osw.remove ();
+	pb.release ();
+	add_button.show ();
+	strip_group_box.pack_start (strip_packer);
+}