From 77356f8e49d541476cc945c497dfdc0fdad3f544 Mon Sep 17 00:00:00 2001
From: Peter Salomonsen <pjsalomonsen@gmail.com>
Date: Fri, 24 Mar 2023 21:44:35 +0100
Subject: [PATCH] Configurable to create empty patterns for the live coding
 environment

---
 song.go        |  9 +++++----
 vm/patterns.go | 13 ++++++++++++-
 2 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/song.go b/song.go
index 335c4e7..4fe93d6 100644
--- a/song.go
+++ b/song.go
@@ -11,10 +11,11 @@ import (
 // playback speed, but this could be changed to a floating point in future if
 // finer adjustments are necessary.
 type Song struct {
-	BPM         int
-	RowsPerBeat int
-	Score       Score
-	Patch       Patch
+	BPM                 int
+	RowsPerBeat         int
+	Score               Score
+	Patch               Patch
+	CreateEmptyPatterns bool
 }
 
 // Copy makes a deep copy of a Score.
diff --git a/vm/patterns.go b/vm/patterns.go
index 671cbce..28dbd46 100644
--- a/vm/patterns.go
+++ b/vm/patterns.go
@@ -162,7 +162,18 @@ func ConstructPatterns(song *sointu.Song) ([][]byte, [][]byte, error) {
 			return nil, nil, errors.New("the constructed pattern table would result in > 256 unique patterns; only 256 unique patterns are supported")
 		}
 	}
-	bytePatterns := make([][]byte, len(patterns))
+
+	// Determine the length of bytePatterns
+	bytePatternsLength := len(patterns)
+	if song.CreateEmptyPatterns {
+		bytePatternsLength = 256
+	}
+
+	bytePatterns := make([][]byte, bytePatternsLength) // Initialize bytePatterns with the specified length
+	for i := 0; i < bytePatternsLength; i++ {
+		bytePatterns[i] = make([]byte, song.Score.RowsPerPattern) // Initialize each element with an array of zeros with length RowsPerPattern
+	}
+
 	for i, pat := range patterns {
 		var err error
 		replaceInts(pat, -1, 0) // replace don't cares with releases