reorganize things into different packages

vm/compiler/song_macros.go

@@ -0,0 +1,39 @@
+package compiler
+
+import (
+	"fmt"
+
+	"github.com/vsariola/sointu"
+)
+
+type SongMacros struct {
+	Song              *sointu.Song
+	VoiceTrackBitmask int
+	MaxSamples        int
+}
+
+func NewSongMacros(s *sointu.Song) *SongMacros {
+	maxSamples := s.SamplesPerRow() * s.Score.LengthInRows()
+	p := SongMacros{Song: s, MaxSamples: maxSamples}
+	trackVoiceNumber := 0
+	for _, t := range s.Score.Tracks {
+		for b := 0; b < t.NumVoices-1; b++ {
+			p.VoiceTrackBitmask += 1 << trackVoiceNumber
+			trackVoiceNumber++
+		}
+		trackVoiceNumber++ // set all bits except last one
+	}
+	return &p
+}
+
+func (p *SongMacros) NumDelayLines() string {
+	total := 0
+	for _, instr := range p.Song.Patch {
+		for _, unit := range instr.Units {
+			if unit.Type == "delay" {
+				total += unit.Parameters["count"] * (1 + unit.Parameters["stereo"])
+			}
+		}
+	}
+	return fmt.Sprintf("%v", total)
+}