more SMS work

it is able to play some modules... the next step is to bind this to the
Genesis platform

src/engine/macroInt.h

@@ -0,0 +1,31 @@
+#ifndef _MACROINT_H
+#define _MACROINT_H
+
+#include "instrument.h"
+
+class DivMacroInt {
+  DivInstrument* ins;
+  int volPos, arpPos, dutyPos, wavePos;
+  public:
+    unsigned char vol, arp, duty, wave;
+    bool hasVol, hasArp, hasDuty, hasWave;
+    bool hadVol, hadArp, hadDuty, hadWave;
+    void next();
+    void init(DivInstrument* which);
+    DivMacroInt():
+      ins(NULL),
+      vol(0),
+      arp(0),
+      duty(0),
+      wave(0),
+      hasVol(false),
+      hasArp(false),
+      hasDuty(false),
+      hasWave(false),
+      hadVol(false),
+      hadArp(false),
+      hadDuty(false),
+      hadWave(false) {}
+};
+
+#endif