Don't busy-wait when there's nothing to play.

[dcpomatic.git] / src / wx / video_view.cc

diff --git a/src/wx/video_view.cc b/src/wx/video_view.cc
index 7f93f765e72fbc84fcf4dea98fe85642c35ba89c..4edc2cd23a28cf0f3b943fe3a9d6cb409fecd973 100644 (file)
--- a/src/wx/video_view.cc
+++ b/src/wx/video_view.cc
@@ -22,8 +22,10 @@
 #include "wx_util.h"
 #include "film_viewer.h"
 #include "lib/butler.h"
+#include <boost/optional.hpp>
 
 using boost::shared_ptr;
+using boost::optional;
 
 VideoView::VideoView (FilmViewer* viewer)
        : _viewer (viewer)
@@ -89,13 +91,13 @@ VideoView::one_video_frame () const
        return dcpomatic::DCPTime::from_frames (1, video_frame_rate());
 }
 
-/** @return Time in ms until the next frame is due */
-int
+/** @return Time in ms until the next frame is due, or empty if nothing is due */
+optional<int>
 VideoView::time_until_next_frame () const
 {
        if (length() == dcpomatic::DCPTime()) {
                /* There's no content, so this doesn't matter */
-               return 0;
+               return optional<int>();
        }
 
        dcpomatic::DCPTime const next = position() + one_video_frame();