Crossfades: default xfades are now constant-power, -3dB rule, other options are constant power(-6dB) rule or use existing region fade shape as is; provide GUI control over options; fix some inconsistent behaviour regarding xfades when relayering

git-svn-id: svn://localhost/ardour2/branches/3.0@12113 d708f5d6-7413-0410-9779-e7cbd77b26cf

9 files changed, 177 insertions, 34 deletions

diff --git a/gtk2_ardour/session_option_editor.cc b/gtk2_ardour/session_option_editor.cc
index 62d555c13d..fe9e06c3a3 100644
--- a/gtk2_ardour/session_option_editor.cc
+++ b/gtk2_ardour/session_option_editor.cc
@@ -154,6 +154,19 @@ SessionOptionEditor::SessionOptionEditor (Session* s)
 
 	add_option (_("Fades"), cfm);
 
+	ComboOption<CrossfadeChoice>* cfc = new ComboOption<CrossfadeChoice> (
+		"xfade-choice",
+		_("Crossfade Type"),
+		sigc::mem_fun (*_session_config, &SessionConfiguration::get_xfade_choice),
+		sigc::mem_fun (*_session_config, &SessionConfiguration::set_xfade_choice)
+		);
+
+	cfc->add (ConstantPowerMinus3dB, _("Constant Power (-3dB)"));
+	cfc->add (ConstantPowerMinus6dB, _("Constant Power (-6dB)"));
+	cfc->add (RegionFades, _("Use existing Region fade shape"));
+
+	add_option (_("Fades"), cfc);
+
 	add_option (_("Fades"), new SpinOption<float> (
 		_("short-xfade-seconds"),
 		_("Short crossfade length"),
diff --git a/libs/ardour/ardour/audioregion.h b/libs/ardour/ardour/audioregion.h
index 7236cd69a9..87d515d399 100644
--- a/libs/ardour/ardour/audioregion.h
+++ b/libs/ardour/ardour/audioregion.h
@@ -89,6 +89,11 @@ class AudioRegion : public Region
 	bool fade_in_active ()  const { return _fade_in_active; }
 	bool fade_out_active () const { return _fade_out_active; }
 
+	bool fade_in_is_xfade() const { return _fade_in_is_xfade; }
+	void set_fade_in_is_xfade (bool yn);
+	bool fade_out_is_xfade() const { return _fade_out_is_xfade; }
+	void set_fade_out_is_xfade (bool yn);
+
 	boost::shared_ptr<AutomationList> fade_in()  { return _fade_in; }
 	boost::shared_ptr<AutomationList> fade_out() { return _fade_out; }
 	boost::shared_ptr<AutomationList> envelope() { return _envelope; }
@@ -232,6 +237,11 @@ class AudioRegion : public Region
 	boost::shared_ptr<AutomationList> _envelope;
 	uint32_t                          _fade_in_suspended;
 	uint32_t                          _fade_out_suspended;
+	/* This is not a Property because its not subject to user control,
+	   or undo/redo. XXX this may prove to be a mistake.
+	*/
+	bool                              _fade_in_is_xfade;
+	bool                              _fade_out_is_xfade;
 
   protected:
 	/* default constructor for derived (compound) types */
diff --git a/libs/ardour/ardour/playlist.h b/libs/ardour/ardour/playlist.h
index d57df6999b..559a24062b 100644
--- a/libs/ardour/ardour/playlist.h
+++ b/libs/ardour/ardour/playlist.h
@@ -367,7 +367,7 @@ public:
 
 private:
 
-	void setup_layering_indices (RegionList const &) const;
+	void setup_layering_indices (RegionList const &);
 	void coalesce_and_check_crossfades (std::list<Evoral::Range<framepos_t> >);
 	boost::shared_ptr<RegionList> find_regions_at (framepos_t);
 };
diff --git a/libs/ardour/ardour/session_configuration_vars.h b/libs/ardour/ardour/session_configuration_vars.h
index a6147f9140..16ce36020b 100644
--- a/libs/ardour/ardour/session_configuration_vars.h
+++ b/libs/ardour/ardour/session_configuration_vars.h
@@ -26,6 +26,7 @@
 *****************************************************/
 
 CONFIG_VARIABLE (CrossfadeModel, xfade_model, "xfade-model", FullCrossfade)
+CONFIG_VARIABLE (CrossfadeChoice, xfade_choice, "xfade-choice", ConstantPowerMinus3dB)
 CONFIG_VARIABLE (bool, auto_xfade, "auto-xfade", true)
 CONFIG_VARIABLE (float, short_xfade_seconds, "short-xfade-seconds", 0.015)
 CONFIG_VARIABLE (bool, xfades_active, "xfades-active", true)
diff --git a/libs/ardour/ardour/types.h b/libs/ardour/ardour/types.h
index b3c1666dbb..71c00e7520 100644
--- a/libs/ardour/ardour/types.h
+++ b/libs/ardour/ardour/types.h
@@ -406,6 +406,12 @@ namespace ARDOUR {
 		ShortCrossfade
 	};
 
+	enum CrossfadeChoice {
+		RegionFades,
+		ConstantPowerMinus3dB,
+		ConstantPowerMinus6dB,
+	};
+
 	enum ListenPosition {
 		AfterFaderListen,
 		PreFaderListen
@@ -558,7 +564,9 @@ namespace ARDOUR {
 		FadeFast,
 		FadeSlow,
 		FadeLogA,
-		FadeLogB
+		FadeLogB,
+		FadeConstantPowerMinus3dB,
+		FadeConstantPowerMinus6dB,
 	};
 
 } // namespace ARDOUR
@@ -579,6 +587,7 @@ std::istream& operator>>(std::istream& o, ARDOUR::RemoteModel& sf);
 std::istream& operator>>(std::istream& o, ARDOUR::ListenPosition& sf);
 std::istream& operator>>(std::istream& o, ARDOUR::InsertMergePolicy& sf);
 std::istream& operator>>(std::istream& o, ARDOUR::CrossfadeModel& sf);
+std::istream& operator>>(std::istream& o, ARDOUR::CrossfadeChoice& sf);
 std::istream& operator>>(std::istream& o, ARDOUR::SyncSource& sf);
 std::istream& operator>>(std::istream& o, ARDOUR::ShuttleBehaviour& sf);
 std::istream& operator>>(std::istream& o, ARDOUR::ShuttleUnits& sf);
@@ -599,6 +608,7 @@ std::ostream& operator<<(std::ostream& o, const ARDOUR::RemoteModel& sf);
 std::ostream& operator<<(std::ostream& o, const ARDOUR::ListenPosition& sf);
 std::ostream& operator<<(std::ostream& o, const ARDOUR::InsertMergePolicy& sf);
 std::ostream& operator<<(std::ostream& o, const ARDOUR::CrossfadeModel& sf);
+std::ostream& operator<<(std::ostream& o, const ARDOUR::CrossfadeChoice& sf);
 std::ostream& operator<<(std::ostream& o, const ARDOUR::SyncSource& sf);
 std::ostream& operator<<(std::ostream& o, const ARDOUR::ShuttleBehaviour& sf);
 std::ostream& operator<<(std::ostream& o, const ARDOUR::ShuttleUnits& sf);
diff --git a/libs/ardour/audio_playlist.cc b/libs/ardour/audio_playlist.cc
index ebebc62c33..f1c89cc565 100644
--- a/libs/ardour/audio_playlist.cc
+++ b/libs/ardour/audio_playlist.cc
@@ -290,7 +290,6 @@ AudioPlaylist::check_crossfades (Evoral::Range<framepos_t> range)
 				continue;
 			}
 			
-
 			boost::shared_ptr<AudioRegion> top;
 			boost::shared_ptr<AudioRegion> bottom;
 		
@@ -317,8 +316,9 @@ AudioPlaylist::check_crossfades (Evoral::Range<framepos_t> range)
 				 */
 
 				if (done_start.find (top) == done_start.end() && done_end.find (bottom) == done_end.end ()) {
-					/* Top's fade-in will cause an implicit fade-out of bottom */
 
+					/* Top's fade-in will cause an implicit fade-out of bottom */
+					
 					framecnt_t len = 0;
 					switch (_session.config.get_xfade_model()) {
 					case FullCrossfade:
@@ -328,11 +328,22 @@ AudioPlaylist::check_crossfades (Evoral::Range<framepos_t> range)
 						len = _session.config.get_short_xfade_seconds() * _session.frame_rate();
 						break;
 					}
-						
-					top->set_fade_in_length (len);
+					
+					switch (_session.config.get_xfade_choice ()) {
+					case ConstantPowerMinus3dB:
+						top->set_fade_in (FadeConstantPowerMinus3dB, len);
+						break;
+					case ConstantPowerMinus6dB:
+						top->set_fade_in (FadeConstantPowerMinus6dB, len);
+						break;
+					case RegionFades:
+						top->set_fade_in_length (len);
+						break;
+					}
 					top->set_fade_in_active (true);
+					top->set_fade_in_is_xfade (true);
+					
 					done_start.insert (top);
-					done_end.insert (bottom);
 				}
 
 			} else if (c == Evoral::OverlapEnd) {
@@ -349,17 +360,28 @@ AudioPlaylist::check_crossfades (Evoral::Range<framepos_t> range)
 					framecnt_t len = 0;
 					switch (_session.config.get_xfade_model()) {
 					case FullCrossfade:
-						len = bottom->last_frame () - top->first_frame ();
+						len = top->last_frame () - bottom->first_frame ();
 						break;
 					case ShortCrossfade:
 						len = _session.config.get_short_xfade_seconds() * _session.frame_rate();
 						break;
 					}
-
-					top->set_fade_out_length (len);
+					
+					switch (_session.config.get_xfade_choice ()) {
+					case ConstantPowerMinus3dB:
+						top->set_fade_out (FadeConstantPowerMinus3dB, len);
+						break;
+					case ConstantPowerMinus6dB:
+						top->set_fade_out (FadeConstantPowerMinus6dB, len);
+						break;
+					case RegionFades:
+						top->set_fade_out_length (len);
+						break;
+					}
 					top->set_fade_out_active (true);
+					top->set_fade_out_is_xfade (true);
+
 					done_end.insert (top);
-					done_start.insert (bottom);
 				}
 			}
 		}
diff --git a/libs/ardour/audioregion.cc b/libs/ardour/audioregion.cc
index 8992f8ccca..79ee58b410 100644
--- a/libs/ardour/audioregion.cc
+++ b/libs/ardour/audioregion.cc
@@ -137,6 +137,8 @@ AudioRegion::AudioRegion (Session& s, framepos_t start, framecnt_t len, std::str
 	, _envelope (new AutomationList(Evoral::Parameter(EnvelopeAutomation)))
 	, _fade_in_suspended (0)
 	, _fade_out_suspended (0)
+	, _fade_in_is_xfade (false)
+	, _fade_out_is_xfade (false)
 {
 	init ();
 	assert (_sources.size() == _master_sources.size());
@@ -152,6 +154,8 @@ AudioRegion::AudioRegion (const SourceList& srcs)
 	, _envelope (new AutomationList(Evoral::Parameter(EnvelopeAutomation)))
 	, _fade_in_suspended (0)
 	, _fade_out_suspended (0)
+	, _fade_in_is_xfade (false)
+	, _fade_out_is_xfade (false)
 {
 	init ();
 	assert (_sources.size() == _master_sources.size());
@@ -169,6 +173,8 @@ AudioRegion::AudioRegion (boost::shared_ptr<const AudioRegion> other)
 	, _envelope (new AutomationList (*other->_envelope, 0, other->_length))
 	, _fade_in_suspended (0)
 	, _fade_out_suspended (0)
+	, _fade_in_is_xfade (false)
+	, _fade_out_is_xfade (false)
 {
 	/* don't use init here, because we got fade in/out from the other region
 	*/
@@ -193,6 +199,8 @@ AudioRegion::AudioRegion (boost::shared_ptr<const AudioRegion> other, framecnt_t
 	, _envelope (new AutomationList (*other->_envelope, offset, other->_length))
 	, _fade_in_suspended (0)
 	, _fade_out_suspended (0)
+	, _fade_in_is_xfade (false)
+	, _fade_out_is_xfade (false)
 {
 	/* don't use init here, because we got fade in/out from the other region
 	*/
@@ -214,6 +222,8 @@ AudioRegion::AudioRegion (boost::shared_ptr<const AudioRegion> other, const Sour
 	, _envelope (new AutomationList (*other->_envelope))
 	, _fade_in_suspended (0)
 	, _fade_out_suspended (0)
+	, _fade_in_is_xfade (false)
+	, _fade_out_is_xfade (false)
 {
 	/* make-a-sort-of-copy-with-different-sources constructor (used by audio filter) */
 
@@ -235,6 +245,8 @@ AudioRegion::AudioRegion (SourceList& srcs)
 	, _envelope (new AutomationList(Evoral::Parameter(EnvelopeAutomation)))
 	, _fade_in_suspended (0)
 	, _fade_out_suspended (0)
+	, _fade_in_is_xfade (false)
+	, _fade_out_is_xfade (false)
 {
 	init ();
 
@@ -818,6 +830,26 @@ AudioRegion::set_fade_in (FadeShape shape, framecnt_t len)
 		_fade_in->fast_simple_add (len * 0.919355, 0.730556);
 		_fade_in->fast_simple_add (len, 1);
 		break;
+
+	case FadeConstantPowerMinus3dB:
+		_fade_in->fast_simple_add (0.0, 0.0);
+		_fade_in->fast_simple_add ((len * 0.166667), 0.282192);
+		_fade_in->fast_simple_add ((len * 0.333333), 0.518174);
+		_fade_in->fast_simple_add ((len * 0.500000), 0.707946);
+		_fade_in->fast_simple_add ((len * 0.666667), 0.851507);
+		_fade_in->fast_simple_add ((len * 0.833333), 0.948859);
+		_fade_in->fast_simple_add (len, 1.0);
+		break;
+		
+	case FadeConstantPowerMinus6dB:
+		_fade_in->fast_simple_add (0.0, 0.0);
+		_fade_in->fast_simple_add ((len * 0.166667), 0.166366);
+		_fade_in->fast_simple_add ((len * 0.333333), 0.332853);
+		_fade_in->fast_simple_add ((len * 0.500000), 0.499459);
+		_fade_in->fast_simple_add ((len * 0.666667), 0.666186);
+		_fade_in->fast_simple_add ((len * 0.833333), 0.833033);
+		_fade_in->fast_simple_add (len, 1.0);
+		break;
 	}
 
 	_fade_in->thaw ();
@@ -842,47 +874,67 @@ AudioRegion::set_fade_out (FadeShape shape, framecnt_t len)
 
 	switch (shape) {
 	case FadeFast:
-		_fade_out->fast_simple_add (len * 0, 1);
+		_fade_out->fast_simple_add (0.0, 1.0);
 		_fade_out->fast_simple_add (len * 0.023041, 0.697222);
 		_fade_out->fast_simple_add (len * 0.0553,   0.483333);
 		_fade_out->fast_simple_add (len * 0.170507, 0.233333);
 		_fade_out->fast_simple_add (len * 0.370968, 0.0861111);
 		_fade_out->fast_simple_add (len * 0.610599, 0.0333333);
-		_fade_out->fast_simple_add (len * 1, 0);
+		_fade_out->fast_simple_add (1.0, 0.0);
 		break;
 
 	case FadeLogA:
-		_fade_out->fast_simple_add (len * 0, 1);
+		_fade_out->fast_simple_add (0, 1.0);
 		_fade_out->fast_simple_add (len * 0.228111, 0.988889);
 		_fade_out->fast_simple_add (len * 0.347926, 0.972222);
 		_fade_out->fast_simple_add (len * 0.529954, 0.886111);
 		_fade_out->fast_simple_add (len * 0.753456, 0.658333);
 		_fade_out->fast_simple_add (len * 0.9262673, 0.308333);
-		_fade_out->fast_simple_add (len * 1, 0);
+		_fade_out->fast_simple_add (len, 0.0);
 		break;
 
 	case FadeSlow:
-		_fade_out->fast_simple_add (len * 0, 1);
+		_fade_out->fast_simple_add (0.0, 1.0);
 		_fade_out->fast_simple_add (len * 0.305556, 1);
 		_fade_out->fast_simple_add (len * 0.548611, 0.991736);
 		_fade_out->fast_simple_add (len * 0.759259, 0.931129);
 		_fade_out->fast_simple_add (len * 0.918981, 0.68595);
 		_fade_out->fast_simple_add (len * 0.976852, 0.22865);
-		_fade_out->fast_simple_add (len * 1, 0);
+		_fade_out->fast_simple_add (len, 0.0);
 		break;
 
 	case FadeLogB:
-		_fade_out->fast_simple_add (len * 0, 1);
+		_fade_out->fast_simple_add (0.0, 1.0);
 		_fade_out->fast_simple_add (len * 0.080645, 0.730556);
 		_fade_out->fast_simple_add (len * 0.277778, 0.289256);
 		_fade_out->fast_simple_add (len * 0.470046, 0.152778);
 		_fade_out->fast_simple_add (len * 0.695853, 0.0694444);
-		_fade_out->fast_simple_add (len * 1, 0);
+		_fade_out->fast_simple_add (len, 0.0);
 		break;
 
 	case FadeLinear:
-		_fade_out->fast_simple_add (len * 0, 1);
-		_fade_out->fast_simple_add (len * 1, 0);
+		_fade_out->fast_simple_add (0.0, 1.0);
+		_fade_out->fast_simple_add (len, 0.0);
+		break;
+
+	case FadeConstantPowerMinus3dB:
+		_fade_out->fast_simple_add (0.0, 1.0);
+		_fade_out->fast_simple_add ((len * 0.166667), 0.948859);
+		_fade_out->fast_simple_add ((len * 0.333333), 0.851507);
+		_fade_out->fast_simple_add ((len * 0.500000), 0.707946);
+		_fade_out->fast_simple_add ((len * 0.666667), 0.518174);
+		_fade_out->fast_simple_add ((len * 0.833333), 0.282192);
+		_fade_out->fast_simple_add (len, 0.0);
+		break;
+
+	case FadeConstantPowerMinus6dB:
+		_fade_out->fast_simple_add (0.0, 1.0);
+		_fade_out->fast_simple_add ((len * 0.166667), 0.833033);
+		_fade_out->fast_simple_add ((len * 0.333333), 0.666186);
+		_fade_out->fast_simple_add ((len * 0.500000), 0.499459);
+		_fade_out->fast_simple_add ((len * 0.666667), 0.332853);
+		_fade_out->fast_simple_add ((len * 0.833333), 0.166366);
+		_fade_out->fast_simple_add (len, 0.0);
 		break;
 	}
 
@@ -957,6 +1009,7 @@ void
 AudioRegion::set_default_fade_in ()
 {
 	_fade_in_suspended = 0;
+	_fade_in_is_xfade = false;
 	set_fade_in (FadeLinear, 64);
 }
 
@@ -964,6 +1017,7 @@ void
 AudioRegion::set_default_fade_out ()
 {
 	_fade_out_suspended = 0;
+	_fade_out_is_xfade = false;
 	set_fade_out (FadeLinear, 64);
 }
 
@@ -1532,6 +1586,18 @@ AudioRegion::body_range () const
 	return Evoral::Range<framepos_t> (first_frame() + _fade_in->back()->when, last_frame() - _fade_out->back()->when);
 }
 
+void
+AudioRegion::set_fade_in_is_xfade (bool yn)
+{
+	_fade_in_is_xfade = yn;
+}
+
+void
+AudioRegion::set_fade_out_is_xfade (bool yn)
+{
+	_fade_out_is_xfade = yn;
+}
+
 extern "C" {
 
 	int region_read_peaks_from_c (void *arg, uint32_t npeaks, uint32_t start, uint32_t cnt, intptr_t data, uint32_t n_chan, double samples_per_unit)
diff --git a/libs/ardour/enums.cc b/libs/ardour/enums.cc
index 4559ed457d..eea971e197 100644
--- a/libs/ardour/enums.cc
+++ b/libs/ardour/enums.cc
@@ -73,6 +73,7 @@ setup_enum_writer ()
 	RemoteModel _RemoteModel;
 	DenormalModel _DenormalModel;
 	CrossfadeModel _CrossfadeModel;
+	CrossfadeChoice _CrossfadeChoice;
 	InsertMergePolicy _InsertMergePolicy;
 	ListenPosition _ListenPosition;
 	SampleFormat _SampleFormat;
@@ -257,6 +258,11 @@ setup_enum_writer ()
 	REGISTER_ENUM (ShortCrossfade);
 	REGISTER (_CrossfadeModel);
 
+	REGISTER_ENUM (RegionFades);
+	REGISTER_ENUM (ConstantPowerMinus3dB);
+	REGISTER_ENUM (ConstantPowerMinus6dB);
+	REGISTER (_CrossfadeChoice);
+
         REGISTER_ENUM (InsertMergeReject);
         REGISTER_ENUM (InsertMergeRelax);
         REGISTER_ENUM (InsertMergeReplace);
@@ -411,6 +417,8 @@ setup_enum_writer ()
 	REGISTER_ENUM (FadeSlow);
 	REGISTER_ENUM (FadeLogA);
 	REGISTER_ENUM (FadeLogB);
+	REGISTER_ENUM (FadeConstantPowerMinus3dB);
+	REGISTER_ENUM (FadeConstantPowerMinus6dB);
 	REGISTER (_FadeShape);
 
 	REGISTER_CLASS_ENUM (Diskstream, Recordable);
@@ -732,6 +740,21 @@ std::ostream& operator<<(std::ostream& o, const CrossfadeModel& var)
 	std::string s = enum_2_string (var);
 	return o << s;
 }
+
+std::istream& operator>>(std::istream& o, CrossfadeChoice& var)
+{
+	std::string s;
+	o >> s;
+	var = (CrossfadeChoice) string_2_enum (s, var);
+	return o;
+}
+
+std::ostream& operator<<(std::ostream& o, const CrossfadeChoice& var)
+{
+	std::string s = enum_2_string (var);
+	return o << s;
+}
+
 std::istream& operator>>(std::istream& o, SyncSource& var)
 {
 	std::string s;
diff --git a/libs/ardour/playlist.cc b/libs/ardour/playlist.cc
index b146f942bd..29be9ec49d 100644
--- a/libs/ardour/playlist.cc
+++ b/libs/ardour/playlist.cc
@@ -608,11 +608,7 @@ Playlist::flush_notifications (bool from_undo)
 		*/
 	}
 
-	if (
-		((regions_changed || pending_contents_change) && !in_set_state) ||
-		pending_layering
-		) {
-		
+	if (((regions_changed || pending_contents_change) && !in_set_state) || pending_layering) {
 		relayer ();
 	}
 
@@ -2276,14 +2272,22 @@ Playlist::set_layer (boost::shared_ptr<Region> region, double new_layer)
 }
 
 void
-Playlist::setup_layering_indices (RegionList const & regions) const
+Playlist::setup_layering_indices (RegionList const & regions)
 {
 	uint64_t j = 0;
+	list<Evoral::Range<framepos_t> > xf;
+
 	for (RegionList::const_iterator k = regions.begin(); k != regions.end(); ++k) {
 		(*k)->set_layering_index (j++);
+
+		Evoral::Range<framepos_t> r ((*k)->first_frame(), (*k)->last_frame());
+		xf.push_back (r);
 	}
-}
 
+	/* now recheck the entire playlist for crossfades */
+
+	coalesce_and_check_crossfades (xf);
+}
 
 /** Take the layering indices of each of our regions, compute the layers
  *  that they should be on, and write the layers back to the regions.
@@ -2677,12 +2681,6 @@ Playlist::shuffle (boost::shared_ptr<Region> region, int dir)
 	if (moved) {
 
 		relayer ();
-
-		list<Evoral::Range<framepos_t> > xf;
-		xf.push_back (old_range);
-		xf.push_back (region->range ());
-		coalesce_and_check_crossfades (xf);
-
 		notify_contents_changed();
 	}