From 28e4e36b00455b3b543704a4d284b6ab69aabe75 Mon Sep 17 00:00:00 2001
From: Paul Davis <paul@linuxaudiosystems.com>
Date: Thu, 5 Aug 2021 15:56:14 -0600
Subject: [PATCH] triggerbox: somewhat more sane behavior at sample end

---
 libs/ardour/ardour/triggerbox.h |  3 ++-
 libs/ardour/triggerbox.cc       | 37 ++++++++++++++++++++++++++-------
 2 files changed, 32 insertions(+), 8 deletions(-)

diff --git a/libs/ardour/ardour/triggerbox.h b/libs/ardour/ardour/triggerbox.h
index f59daedef5..38e495f609 100644
--- a/libs/ardour/ardour/triggerbox.h
+++ b/libs/ardour/ardour/triggerbox.h
@@ -85,6 +85,7 @@ class LIBARDOUR_API Trigger {
 
 	bool stop_requested() const { return _stop_requested; }
 	virtual void stop();
+	virtual void retrigger () {}
 
 	size_t index() const { return _index; }
 
@@ -115,6 +116,7 @@ class LIBARDOUR_API AudioTrigger : public Trigger {
 	Sample* run (uint32_t channel, pframes_t& nframes, bool& need_butler);
 
 	int set_region (boost::shared_ptr<Region>);
+	void retrigger ();
 
   private:
 	std::vector<Sample*> data;
@@ -123,7 +125,6 @@ class LIBARDOUR_API AudioTrigger : public Trigger {
 
 	void drop_data ();
 	int load_data (boost::shared_ptr<AudioRegion>);
-	void retrigger ();
 };
 
 class LIBARDOUR_API TriggerBox : public Processor
diff --git a/libs/ardour/triggerbox.cc b/libs/ardour/triggerbox.cc
index 8e04ce5f48..e167728b2c 100644
--- a/libs/ardour/triggerbox.cc
+++ b/libs/ardour/triggerbox.cc
@@ -326,13 +326,19 @@ TriggerBox::run (BufferSet& bufs, samplepos_t start_sample, samplepos_t end_samp
 		}
 	}
 
-	bool err = false;
 	bool need_butler = false;
 	size_t max_chans = 0;
 
-	for (Triggers::iterator t = active_triggers.begin(); !err && t != active_triggers.end(); ++t) {
+	for (Triggers::iterator t = active_triggers.begin(); t != active_triggers.end(); ) {
 
 		Trigger* trigger = (*t);
+		boost::shared_ptr<Region> r = trigger->region();
+
+		if (!r) {
+			t = active_triggers.erase (t);
+			continue;
+		}
+
 		sampleoffset_t dest_offset = 0;
 		pframes_t trigger_samples = nframes;
 
@@ -346,11 +352,12 @@ TriggerBox::run (BufferSet& bufs, samplepos_t start_sample, samplepos_t end_samp
 
 		AudioTrigger* at = dynamic_cast<AudioTrigger*> (trigger);
 
-		boost::shared_ptr<AudioRegion> ar = boost::dynamic_pointer_cast<AudioRegion> (trigger->region());
+		boost::shared_ptr<AudioRegion> ar = boost::dynamic_pointer_cast<AudioRegion> (r);
 		const size_t nchans = ar->n_channels ();
 		max_chans = std::max (max_chans, nchans);
 
-		for (uint32_t chan = 0; !err && chan < nchans; ++chan) {
+		bool at_end = false;
+		for (uint32_t chan = 0; !at_end && chan < nchans; ++chan) {
 
 			AudioBuffer& buf = bufs.get_audio (chan);
 
@@ -358,9 +365,8 @@ TriggerBox::run (BufferSet& bufs, samplepos_t start_sample, samplepos_t end_samp
 			Sample* data = at->run (chan, to_copy, need_butler);
 
 			if (!data) {
-				/* XXX need to delete the trigger/put it back in the pool */
-				t = active_triggers.erase (t);
-				err = true;
+				at_end = true;
+				break;
 			} else {
 				if (t == active_triggers.begin()) {
 					buf.read_from (data, to_copy, dest_offset);
@@ -373,6 +379,23 @@ TriggerBox::run (BufferSet& bufs, samplepos_t start_sample, samplepos_t end_samp
 			}
 
 		}
+		if (at_end) {
+
+			switch (trigger->launch_style()) {
+			case Trigger::Loop:
+				trigger->retrigger();
+				++t;
+				break;
+			case Trigger::Gate:
+			case Trigger::Toggle:
+			case Trigger::Repeat:
+				t = active_triggers.erase (t);
+				break;
+			}
+
+		} else {
+			++t;
+		}
 	}
 
 	ChanCount cc (DataType::AUDIO, max_chans);