From bad08a26323534d638ecd2fed854edc40b33d36b Mon Sep 17 00:00:00 2001
From: Vesa <contact.diizy@nbl.fi>
Date: Fri, 6 Jun 2014 14:24:51 +0300
Subject: [PATCH] Ensure that NotePlayHandles get processed before the
 InstrumentPlayHandle on instruments that use both NotePlayHandles and
 InstrumentPlayHandle, such as LB302 and SF2-Player Issue: Currently, we use
 threads to process all PlayHandles, so there's no guarantee of the order they
 are processed in. This causes timing inaccuracy and jitter: notes of
 instruments that use both NPH's and IPH's can get randomly delayed by one
 entire period. The issue is solved thusly: - When processing an IPH, we check
 if the instrument is midi-based. If yes, we just process it normally (no
 NPH's to worry about). - If it's not, then it also uses NPH's, so we'll have
 the IPH wait until all NPH's belonging to same instrument have been
 processed. There's some similar code in the new FX mixer, I pretty much just
 copied how we do it there.

---
 include/Instrument.h            |  4 ++--
 include/InstrumentPlayHandle.h  | 24 ++++++++++++++++++++++--
 plugins/sf2_player/sf2_player.h |  2 +-
 3 files changed, 25 insertions(+), 5 deletions(-)

diff --git a/include/Instrument.h b/include/Instrument.h
index 3db88b980..88c8e9a19 100644
--- a/include/Instrument.h
+++ b/include/Instrument.h
@@ -119,13 +119,13 @@ public:
 
 	virtual bool isFromTrack( const track * _track ) const;
 
-
-protected:
 	inline InstrumentTrack * instrumentTrack() const
 	{
 		return m_instrumentTrack;
 	}
 
+
+protected:
 	// instruments may use this to apply a soft fade out at the end of
 	// notes - method does this only if really less or equal
 	// desiredReleaseFrames() frames are left
diff --git a/include/InstrumentPlayHandle.h b/include/InstrumentPlayHandle.h
index cf472db9e..c2fd5c918 100644
--- a/include/InstrumentPlayHandle.h
+++ b/include/InstrumentPlayHandle.h
@@ -22,11 +22,12 @@
  *
  */
 
-#ifndef _INSTRUMENT_PLAY_HANDLE_H
-#define _INSTRUMENT_PLAY_HANDLE_H
+#ifndef INSTRUMENT_PLAY_HANDLE_H
+#define INSTRUMENT_PLAY_HANDLE_H
 
 #include "PlayHandle.h"
 #include "Instrument.h"
+#include "NotePlayHandle.h"
 
 
 class InstrumentPlayHandle : public PlayHandle
@@ -45,6 +46,25 @@ public:
 
 	virtual void play( sampleFrame * _working_buffer )
 	{
+		// if the instrument is midi-based, we can safely render right away
+		if( m_instrument->flags() & Instrument::IsMidiBased )
+		{
+			m_instrument->play( _working_buffer );
+			return;
+		}
+		
+		// if not, we need to ensure that all our nph's have been processed first
+		ConstNotePlayHandleList nphv = NotePlayHandle::nphsOfInstrumentTrack( m_instrument->instrumentTrack(), true );
+		
+		foreach( const NotePlayHandle * cnph, nphv )
+		{
+			NotePlayHandle * nph = const_cast<NotePlayHandle *>( cnph );
+			while( nph->state() != ThreadableJob::Done )
+			{
+				nph->process();
+			}
+		}
+		
 		m_instrument->play( _working_buffer );
 	}
 
diff --git a/plugins/sf2_player/sf2_player.h b/plugins/sf2_player/sf2_player.h
index e27aa8a8a..5c2f5beb8 100644
--- a/plugins/sf2_player/sf2_player.h
+++ b/plugins/sf2_player/sf2_player.h
@@ -79,7 +79,7 @@ public:
 
 	virtual Flags flags() const
 	{
-		return IsSingleStreamed | IsMidiBased;
+		return IsSingleStreamed;
 	}
 
 	virtual PluginView * instantiateView( QWidget * _parent );