make region opacity work again; fix several other region context menu items that may have been messing with region state in unforeseen ways

git-svn-id: svn://localhost/ardour2/trunk@1691 d708f5d6-7413-0410-9779-e7cbd77b26cf

3 files changed, 52 insertions, 20 deletions

diff --git a/libs/ardour/ardour/audioregion.h b/libs/ardour/ardour/audioregion.h
index 92f678a1a2..a450d90008 100644
--- a/libs/ardour/ardour/audioregion.h
+++ b/libs/ardour/ardour/audioregion.h
@@ -65,7 +65,7 @@ class AudioRegion : public Region
 	
 	void normalize_to (float target_in_dB = 0.0f);
 
-	uint32_t n_channels() { return sources.size(); }
+	uint32_t n_channels() const { return sources.size(); }
 	vector<string> master_source_names();
 	
 	bool envelope_active () const { return _flags & Region::EnvelopeActive; }
@@ -95,6 +95,8 @@ class AudioRegion : public Region
 	int      set_state (const XMLNode&);
 
 	static void set_default_fade (float steepness, nframes_t len);
+	bool fade_in_is_default () const;
+	bool fade_out_is_default () const;
 
 	enum FadeShape {
 		Linear,
diff --git a/libs/ardour/audioregion.cc b/libs/ardour/audioregion.cc
index db6e5fc089..1d3032c1e0 100644
--- a/libs/ardour/audioregion.cc
+++ b/libs/ardour/audioregion.cc
@@ -452,12 +452,12 @@ AudioRegion::_read_at (const SourceList& srcs, Sample *buf, Sample *mixdown_buff
 	nframes_t buf_offset;
 	nframes_t to_read;
 
-	/* precondition: caller has verified that we cover the desired section */
-
-	if (chan_n >= sources.size()) {
+	if (muted()) {
 		return 0; /* read nothing */
 	}
-	
+
+	/* precondition: caller has verified that we cover the desired section */
+
 	if (position < _position) {
 		internal_offset = 0;
 		buf_offset = _position - position;
@@ -482,17 +482,29 @@ AudioRegion::_read_at (const SourceList& srcs, Sample *buf, Sample *mixdown_buff
 		mixdown_buffer += buf_offset;
 	}
 
-	if (muted()) {
-		return 0; /* read nothing */
-	}
-
 	_read_data_count = 0;
 
-	if (srcs[chan_n]->read (mixdown_buffer, _start + internal_offset, to_read) != to_read) {
-		return 0; /* "read nothing" */
-	}
+	if (chan_n < n_channels()) {
+
+		if (srcs[chan_n]->read (mixdown_buffer, _start + internal_offset, to_read) != to_read) {
+			
+			return 0; /* "read nothing" */
+		}
+		
+		_read_data_count += srcs[chan_n]->read_data_count();
 
-	_read_data_count += srcs[chan_n]->read_data_count();
+	} else {
+		
+		/* track is N-channel, this region has less channels; silence the ones
+		   we don't have.
+		*/
+
+		memset (mixdown_buffer, 0, sizeof (Sample) * cnt);
+
+		/* no fades required */
+
+		goto merge;
+	}
 
 	/* fade in */
 
@@ -503,7 +515,7 @@ AudioRegion::_read_at (const SourceList& srcs, Sample *buf, Sample *mixdown_buff
 		/* see if this read is within the fade in */
 
 		if (internal_offset < fade_in_length) {
-			
+		
 			nframes_t limit;
 
 			limit = min (to_read, fade_in_length - internal_offset);
@@ -577,13 +589,15 @@ AudioRegion::_read_at (const SourceList& srcs, Sample *buf, Sample *mixdown_buff
 		Session::apply_gain_to_buffer (mixdown_buffer, to_read, _scale_amplitude);
 	}
 
+  merge:
+
 	if (!opaque()) {
 
 		/* gack. the things we do for users.
 		 */
 
 		buf += buf_offset;
-
+		
 		for (nframes_t n = 0; n < to_read; ++n) {
 			buf[n] += mixdown_buffer[n];
 		}
@@ -946,6 +960,18 @@ AudioRegion::set_fade_out_active (bool yn)
 	send_change (FadeOutActiveChanged);
 }
 
+bool
+AudioRegion::fade_in_is_default () const
+{
+	return _fade_in_shape == Linear && _fade_in.back()->when == 64;
+}
+
+bool
+AudioRegion::fade_out_is_default () const
+{
+	return _fade_out_shape == Linear && _fade_out.back()->when == 64;
+}
+
 void
 AudioRegion::set_default_fade_in ()
 {
@@ -1310,14 +1336,16 @@ void
 AudioRegion::suspend_fade_in ()
 {
 	if (++_fade_in_disabled == 1) {
-		set_fade_in_active (false);
+		if (fade_in_is_default()) {
+			set_fade_in_active (false);
+		}
 	}
 }
 
 void
 AudioRegion::resume_fade_in ()
 {
-	if (_fade_in_disabled && --_fade_in_disabled == 0) {
+	if (--_fade_in_disabled == 0 && _fade_in_disabled) {
 		set_fade_in_active (true);
 	}
 }
@@ -1326,14 +1354,16 @@ void
 AudioRegion::suspend_fade_out ()
 {
 	if (++_fade_out_disabled == 1) {
-		set_fade_out_active (false);
+		if (fade_out_is_default()) {
+			set_fade_out_active (false);
+		}
 	}
 }
 
 void
 AudioRegion::resume_fade_out ()
 {
-	if (_fade_out_disabled && --_fade_out_disabled == 0) {
+	if (--_fade_out_disabled == 0 &&_fade_out_disabled) {
 		set_fade_out_active (true);
 	}
 }
diff --git a/libs/ardour/session_butler.cc b/libs/ardour/session_butler.cc
index 16c8d9cffa..afb284b0f4 100644
--- a/libs/ardour/session_butler.cc
+++ b/libs/ardour/session_butler.cc
@@ -248,7 +248,7 @@ Session::butler_thread_work ()
 		gettimeofday (&begin, 0);
 
 		boost::shared_ptr<DiskstreamList> dsl = diskstreams.reader ();
-		
+
 		for (i = dsl->begin(); !transport_work_requested() && butler_should_run && i != dsl->end(); ++i) {
 
 			boost::shared_ptr<Diskstream> ds = *i;