From c55b27b23b8942142694c8c295e8217d1d38ea4b Mon Sep 17 00:00:00 2001
From: "5684185+vsariola@users.noreply.github.com"
 <5684185+vsariola@users.noreply.github.com>
Date: Sun, 10 Mar 2024 20:01:13 +0200
Subject: [PATCH] fix(tracker): recording creates empty track when no notes
 triggered

---
 CHANGELOG.md         | 2 ++
 tracker/recording.go | 6 ++++++
 2 files changed, 8 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 72ccddd..01c9555 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -23,6 +23,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
   ([#65][i65])
 
 ### Fixed
+- When recording notes from VSTI, no track was created for instruments that had
+  no notes triggered, resulting in misalignment of the tracks from instruments.
 - 32-bit su_load_gmdls clobbered ebx, even though __stdcall demands it to be not
   touched ([#130][i130])
 - Spaces are allowed in instrument names ([#120][i120])
diff --git a/tracker/recording.go b/tracker/recording.go
index 2b088c1..8f4b1ba 100644
--- a/tracker/recording.go
+++ b/tracker/recording.go
@@ -77,6 +77,12 @@ func (recording *Recording) Score(patch sointu.Patch, rowsPerBeat, rowsPerPatter
 			tracks[i][oldestIndex] = append(tracks[i][oldestIndex], n)
 		}
 	}
+	// if there was tracks that had no notes, create empty tracks for them
+	for i := range channelNotes {
+		if l := len(tracks[i]); l == 0 && l < patch[i].NumVoices {
+			tracks[i] = append(tracks[i], []recordingNote{})
+		}
+	}
 	songLengthPatterns := (frameToRow(recording.BPM, rowsPerBeat, recording.TotalFrames) + rowsPerPattern - 1) / rowsPerPattern
 	songLengthRows := songLengthPatterns * rowsPerPattern
 	songTracks := make([]sointu.Track, 0)