Split subtitles at reel boundaries (#1918).

[dcpomatic.git] / src / lib / writer.cc

diff --git a/src/lib/writer.cc b/src/lib/writer.cc
index ad588f0a62aa0ff0709168c89c304666ec0867fe..4386b8e26264dea29a1e4cc41dce74212e915465 100644 (file)
--- a/src/lib/writer.cc
+++ b/src/lib/writer.cc
@@ -545,6 +545,7 @@ Writer::finish (boost::filesystem::path output_dcp)
        LOG_GENERAL_NC ("Finishing ReelWriters");
 
        for (auto& i: _reels) {
+               write_hanging_text (i);
                i.finish (output_dcp);
        }
 
@@ -798,6 +799,23 @@ Writer::write (PlayerText text, TextType type, optional<DCPTextTrack> track, DCP
        while ((*reel)->period().to <= period.from) {
                ++(*reel);
                DCPOMATIC_ASSERT (*reel != _reels.end());
+               write_hanging_text (**reel);
+       }
+
+       if (period.to > (*reel)->period().to) {
+               /* This text goes off the end of the reel.  Store parts of it that should go into
+                * other reels.
+                */
+               for (auto i = std::next(*reel); i != _reels.end(); ++i) {
+                       auto overlap = i->period().overlap(period);
+                       if (overlap) {
+                               _hanging_texts.push_back (HangingText{text, type, track, *overlap});
+                       }
+               }
+               /* Back off from the reel boundary by a couple of frames to avoid tripping checks
+                * for subtitles being too close together.
+                */
+               period.to = (*reel)->period().to - DCPTime::from_frames(2, film()->video_frame_rate());
        }
 
        (*reel)->write (text, type, track, period);
@@ -907,3 +925,17 @@ Writer::calculate_referenced_digests (boost::function<void (float)> set_progress
        }
 }
 
+
+void
+Writer::write_hanging_text (ReelWriter& reel)
+{
+       vector<HangingText> new_hanging_texts;
+       for (auto i: _hanging_texts) {
+               if (i.period.from == reel.period().from) {
+                       reel.write (i.text, i.type, i.track, i.period);
+               } else {
+                       new_hanging_texts.push_back (i);
+               }
+       }
+       _hanging_texts = new_hanging_texts;
+}