Express trims using ContentTime so that they do not change

when DCP frame rate is changed (#637).

6 files changed, 64 insertions, 41 deletions

diff --git a/src/lib/content.cc b/src/lib/content.cc
index 2b4f02b90..65c005157 100644
--- a/src/lib/content.cc
+++ b/src/lib/content.cc
@@ -88,9 +88,9 @@ Content::Content (shared_ptr<const Film> film, cxml::ConstNodePtr node)
 		_paths.push_back ((*i)->content ());
 	}
 	_digest = node->optional_string_child ("Digest").get_value_or ("X");
-	_position = DCPTime (node->number_child<double> ("Position"));
-	_trim_start = DCPTime (node->number_child<double> ("TrimStart"));
-	_trim_end = DCPTime (node->number_child<double> ("TrimEnd"));
+	_position = DCPTime (node->number_child<DCPTime::Type> ("Position"));
+	_trim_start = ContentTime (node->number_child<ContentTime::Type> ("TrimStart"));
+	_trim_end = ContentTime (node->number_child<ContentTime::Type> ("TrimEnd"));
 }
 
 Content::Content (shared_ptr<const Film> film, vector<shared_ptr<Content> > c)
@@ -101,11 +101,11 @@ Content::Content (shared_ptr<const Film> film, vector<shared_ptr<Content> > c)
 	, _change_signals_frequent (false)
 {
 	for (size_t i = 0; i < c.size(); ++i) {
-		if (i > 0 && c[i]->trim_start() > DCPTime()) {
+		if (i > 0 && c[i]->trim_start() > ContentTime ()) {
 			throw JoinError (_("Only the first piece of content to be joined can have a start trim."));
 		}
 
-		if (i < (c.size() - 1) && c[i]->trim_end () > DCPTime()) {
+		if (i < (c.size() - 1) && c[i]->trim_end () > ContentTime ()) {
 			throw JoinError (_("Only the last piece of content to be joined can have an end trim."));
 		}
 
@@ -172,7 +172,7 @@ Content::set_position (DCPTime p)
 }
 
 void
-Content::set_trim_start (DCPTime t)
+Content::set_trim_start (ContentTime t)
 {
 	{
 		boost::mutex::scoped_lock lm (_mutex);
@@ -183,7 +183,7 @@ Content::set_trim_start (DCPTime t)
 }
 
 void
-Content::set_trim_end (DCPTime t)
+Content::set_trim_end (ContentTime t)
 {
 	{
 		boost::mutex::scoped_lock lm (_mutex);
@@ -221,7 +221,9 @@ Content::technical_summary () const
 DCPTime
 Content::length_after_trim () const
 {
-	return max (DCPTime (), full_length() - trim_start() - trim_end());
+	shared_ptr<const Film> film = _film.lock ();
+	DCPOMATIC_ASSERT (film);
+	return max (DCPTime (), full_length() - DCPTime (trim_start() - trim_end(), film->active_frame_rate_change (position ())));
 }
 
 /** @return string which includes everything about how this content affects
diff --git a/src/lib/content.h b/src/lib/content.h
index 2deee9763..b7f7987ef 100644
--- a/src/lib/content.h
+++ b/src/lib/content.h
@@ -128,16 +128,16 @@ public:
 		return _position;
 	}
 
-	void set_trim_start (DCPTime);
+	void set_trim_start (ContentTime);
 
-	DCPTime trim_start () const {
+	ContentTime trim_start () const {
 		boost::mutex::scoped_lock lm (_mutex);
 		return _trim_start;
 	}
 
-	void set_trim_end (DCPTime);
+	void set_trim_end (ContentTime);
 
-	DCPTime trim_end () const {
+	ContentTime trim_end () const {
 		boost::mutex::scoped_lock lm (_mutex);
 		return _trim_end;
 	}
@@ -176,8 +176,8 @@ protected:
 private:
 	std::string _digest;
 	DCPTime _position;
-	DCPTime _trim_start;
-	DCPTime _trim_end;
+	ContentTime _trim_start;
+	ContentTime _trim_end;
 	bool _change_signals_frequent;
 };
 
diff --git a/src/lib/dcpomatic_time.cc b/src/lib/dcpomatic_time.cc
index 4541ced7d..3d4ed1139 100644
--- a/src/lib/dcpomatic_time.cc
+++ b/src/lib/dcpomatic_time.cc
@@ -45,6 +45,36 @@ min (DCPTime a, DCPTime b)
 	return b;
 }
 
+DCPTime
+max (DCPTime a, DCPTime b)
+{
+	if (a > b) {
+		return a;
+	}
+
+	return b;
+}
+
+ContentTime
+min (ContentTime a, ContentTime b)
+{
+	if (a < b) {
+		return a;
+	}
+
+	return b;
+}
+
+ContentTime
+max (ContentTime a, ContentTime b)
+{
+	if (a > b) {
+		return a;
+	}
+
+	return b;
+}
+
 ostream &
 operator<< (ostream& s, ContentTime t)
 {
diff --git a/src/lib/dcpomatic_time.h b/src/lib/dcpomatic_time.h
index 698815957..437b78f62 100644
--- a/src/lib/dcpomatic_time.h
+++ b/src/lib/dcpomatic_time.h
@@ -241,6 +241,9 @@ public:
 };
 
 DCPTime min (DCPTime a, DCPTime b);
+DCPTime max (DCPTime a, DCPTime b);
+ContentTime min (ContentTime a, ContentTime b);
+ContentTime max (ContentTime a, ContentTime b);
 std::ostream& operator<< (std::ostream& s, ContentTime t);
 std::ostream& operator<< (std::ostream& s, DCPTime t);
 
diff --git a/src/lib/player.cc b/src/lib/player.cc
index c551c9886..a289c3d92 100644
--- a/src/lib/player.cc
+++ b/src/lib/player.cc
@@ -522,48 +522,33 @@ Frame
 Player::dcp_to_content_video (shared_ptr<const Piece> piece, DCPTime t) const
 {
 	shared_ptr<const VideoContent> vc = dynamic_pointer_cast<const VideoContent> (piece->content);
-
-	DCPTime s = t - piece->content->position () + piece->content->trim_start ();
-	s = DCPTime (max (DCPTime::Type (0), s.get ()));
-	s = DCPTime (min (piece->content->length_after_trim().get(), s.get()));
-
-	return ContentTime (s, piece->frc).frames (vc->video_frame_rate ());
+	DCPTime s = t - piece->content->position ();
+	s = min (piece->content->length_after_trim(), s);
+	return max (ContentTime (), ContentTime (s, piece->frc) + piece->content->trim_start ()).frames (vc->video_frame_rate ());
 }
 
 DCPTime
 Player::content_video_to_dcp (shared_ptr<const Piece> piece, Frame f) const
 {
 	shared_ptr<const VideoContent> vc = dynamic_pointer_cast<const VideoContent> (piece->content);
-
-	ContentTime const c = ContentTime::from_frames (f, vc->video_frame_rate ());
-	DCPTime t = DCPTime (c, piece->frc) - piece->content->trim_start () + piece->content->position ();
-
-	if (t < DCPTime ()) {
-		t = DCPTime ();
-	}
-
-	return t;
+	ContentTime const c = ContentTime::from_frames (f, vc->video_frame_rate ()) - piece->content->trim_start ();
+	return max (DCPTime (), DCPTime (c, piece->frc) + piece->content->position ());
 }
 
 Frame
 Player::dcp_to_content_audio (shared_ptr<const Piece> piece, AudioStreamPtr stream, DCPTime t) const
 {
-	DCPTime s = t - piece->content->position () + piece->content->trim_start ();
-	s = DCPTime (max (DCPTime::Type (0), s.get ()));
-	s = DCPTime (min (piece->content->length_after_trim().get(), s.get()));
-
-	return ContentTime (s, piece->frc).frames (stream->frame_rate ());
+	DCPTime s = t - piece->content->position ();
+	s = min (piece->content->length_after_trim(), s);
+	return max (ContentTime (), ContentTime (s, piece->frc) + piece->content->trim_start ()).frames (stream->frame_rate ());
 }
 
 ContentTime
 Player::dcp_to_content_subtitle (shared_ptr<const Piece> piece, DCPTime t) const
 {
-	/* s is the offset of t from the start position of this content */
 	DCPTime s = t - piece->content->position ();
-	s = DCPTime (max (DCPTime::Type (0), s.get ()));
-	s = DCPTime (min (piece->content->length_after_trim().get(), s.get()));
-
-	return ContentTime (s + piece->content->trim_start(), piece->frc);
+	s = min (piece->content->length_after_trim(), s);
+	return max (ContentTime (), ContentTime (s, piece->frc) + piece->content->trim_start());
 }
 
 void
diff --git a/src/lib/playlist.cc b/src/lib/playlist.cc
index e2135a60e..4e46fdbdf 100644
--- a/src/lib/playlist.cc
+++ b/src/lib/playlist.cc
@@ -303,13 +303,16 @@ Playlist::video_end () const
 FrameRateChange
 Playlist::active_frame_rate_change (DCPTime t, int dcp_video_frame_rate) const
 {
-	for (ContentList::const_iterator i = _content.begin(); i != _content.end(); ++i) {
+	for (ContentList::const_reverse_iterator i = _content.rbegin(); i != _content.rend(); ++i) {
 		shared_ptr<const VideoContent> vc = dynamic_pointer_cast<const VideoContent> (*i);
 		if (!vc) {
 			continue;
 		}
 
-		if (vc->position() >= t && t < vc->end()) {
+		if (vc->position() <= t) {
+			/* This is the first piece of content (going backwards...) that starts before t,
+			   so it's the active one.
+			*/
 			return FrameRateChange (vc->video_frame_rate(), dcp_video_frame_rate);
 		}
 	}