Update MIDI demo to save CPU cycles

Demonstrates using OSC system to poll active envelopes, and shut the source AudioSynthWaveform sources down when the release phase ends. Of course, the polling may take more CPU than the waveforms ... I haven't checked that!

examples/OSCAudioMIDIgroupsFS/MIDI.ino

@@ -59,7 +59,8 @@ float note2freq(byte note,float* scale)
   return freq;
 }
 
-void dbgMIDI(byte ch, byte typ, byte d1, byte d2)
+void dbgMIDI(byte ch, byte typ, byte d1, byte d2){}
+void dbgMIDIx(byte ch, byte typ, byte d1, byte d2)
 {
     Serial.printf("%02X: %02X,%02X,%02X\n",
                   ch,typ,d1,d2);
@@ -76,6 +77,7 @@ void dbgMIDIget(void)
 //-----------------------------------------------------
 #define AVAIL 0xFF
 byte allocate[4];
+byte pending[4];
 // return index in allocate array of available voice,
 // or one that's already playing this note. Also
 // mark slot as "taken" by this note.
@@ -101,6 +103,7 @@ int deallocateMIDI(byte note)
     if (note == allocate[i])
     {
       allocate[i] = AVAIL;
+      pending[i] = note;
       break;
     }
 
@@ -123,9 +126,9 @@ void OSCnoteOn(byte channel, byte note, byte velocity)
   {
     char buf[50];
 
-    Serial.print("\nNote on: ");
+    //Serial.print("\nNote on: ");
     freq = note2freq(note,wellTempered);
-    Serial.println(freq);
+    //Serial.println(freq);
     dbgMIDI(channel,0x80,note,velocity);  
 
     uint32_t st = micros();
@@ -151,7 +154,59 @@ void OSCnoteOn(byte channel, byte note, byte velocity)
     reply.add("/noteOn");
     processBundle(&bndl,reply);
     st = micros() - st;
-    Serial.printf("OSC processing took %d us\n",st);
+    //Serial.printf("OSC processing took %d us\n",st);
+  }
+}
+
+
+// poll all releasing envelopes to see
+// if we can stop the associated waveforms
+// to save some CPU load
+uint32_t nextPoll;
+void pollMIDIstopWav()
+{
+  if (millis() > nextPoll) 
+  {
+    nextPoll = millis() + 10; // only poll every 10ms or so
+
+    for (size_t i=0;i<COUNT_OF(pending);i++)  
+    {
+      if (pending[i] != AVAIL) // only poll envelopes that are pending release completion
+      {
+        OSCBundle bndl, reply;
+        char buf[50];
+        bool envActive;
+        int slot = i;
+
+#if !defined(USE_GROUPS)    
+        sprintf(buf,"/teensy1/audio/env%c/isAc",slot+'A');
+#else      
+        sprintf(buf,"/teensy1/audio/voice1/i%c/env/isAc",slot+'0');
+#endif      
+        bndl.add(buf);
+        reply.add("/inactive");
+        processBundle(&bndl,reply);
+
+        envActive = reply.getOSCMessage(0)->getBoolean(2);
+        if (!envActive)
+        {
+          pending[i] = AVAIL;
+          bndl.empty();
+          reply.empty();
+
+#if !defined(USE_GROUPS)    
+          sprintf(buf,"/teensy1/audio/wav%c1/amp",slot+'A');
+          bndl.add(buf).add(0.0f);
+          sprintf(buf,"/teensy1/audio/wav%c2/amp",slot+'A');
+          bndl.add(buf).add(0.0f);
+#else    
+          sprintf(buf,"/teensy1/audio/voice1/i%c/wa*/amp",slot+'0');
+          bndl.add(buf).add(0.0f);
+#endif // !defined(USE_GROUPS)            
+          reply.add("/wavStop");
+          processBundle(&bndl,reply);      }    
+      }
+    }
   }
 }
 
@@ -162,7 +217,7 @@ void OSCnoteOff(byte channel, byte note, byte velocity)
   OSCBundle reply;
   int slot = deallocateMIDI(note);
 
-  Serial.print("\nNote off: ");
+  //Serial.print("\nNote off: ");
   dbgMIDI(channel,0x90,note,velocity);    
 
   if (slot >= 0)
@@ -171,12 +226,15 @@ void OSCnoteOff(byte channel, byte note, byte velocity)
 
 #if !defined(USE_GROUPS)    
     sprintf(buf,"/teensy1/audio/env%c/noteOff",slot+'A');
+    bndl.add(buf);
 #else    
     sprintf(buf,"/teensy1/audio/voice1/i%c/env/noteOff",slot+'0');
-#endif // !defined(USE_GROUPS)    
     bndl.add(buf);
+#endif // !defined(USE_GROUPS)    
     reply.add("/noteOff");
     processBundle(&bndl,reply);
+
+    pending[slot] = note; // signal to poll that envelope is releasing
   }
 }
 
@@ -237,7 +295,10 @@ void initMIDI(void)
   usbMIDI.setHandleNoteOn(OSCnoteOn);
   usbMIDI.setHandleControlChange(handleCC);
   for (size_t i=0;i<COUNT_OF(allocate);i++)
+  {
     allocate[i] = AVAIL;
+    pending[i] = AVAIL;
+  }
 }
 
 
@@ -249,6 +310,7 @@ void updateMIDI(void)
     offTime = millis()+100;
     dbgMIDIget(); // mop up untrapped messages
   }
+  pollMIDIstopWav();
 
   if (millis() < offTime)
     digitalWrite(LED_BUILTIN,1);

examples/OSCAudioMIDIgroupsFS/OSCAudioMIDIgroupsFS.ino

@@ -95,8 +95,10 @@ OSCBundle* replyStack; // where reply is currently being built
 // route messages to existing audio objects
 void routeAudio(OSCMessage& msg, int addressOffset)
 {
+  AudioNoInterrupts();
   //Serial.println("audio message!");
   OSCAudioBase::routeAll(msg,addressOffset,*replyStack);
+  AudioInterrupts();
 }
 
 
@@ -105,8 +107,10 @@ void routeAudio(OSCMessage& msg, int addressOffset)
 void routeDynamic(OSCMessage& msg, int addressOffset)
 {
 #if defined(SAFE_RELEASE)  
+  AudioNoInterrupts();
   //Serial.println("dynamic objects message!");
   OSCAudioBase::routeDynamic(msg,addressOffset,*replyStack);
+  AudioInterrupts();
 #else
   Serial.println("dynamic objects not available!");
 #endif // defined(SAFE_RELEASE)  
@@ -216,8 +220,7 @@ void updateOSC()
         msgLen = HWSERIAL.available(); // only ever returns 0 or 1, actually
         while (msgLen--)
         {
-          char c = HWSERIAL.read();
-          //Serial.print(c);
+          char c = HWSERIAL.read();            
           // figure out if it's a message or a bundle
           if (0 == firstCh)
             firstCh = c;

examples/OSCAudioMIDIgroupsFS/utils.ino

@@ -16,7 +16,7 @@ void listObjects(OSCAudioBase* obj,int indent=0)
     OSCAudioConnection* conn = obj->getFirstSrc();
 
     prIndent(indent);
-    Serial.printf("%s is at %08X; route: %08X",obj->name,(uint32_t) obj,(uint32_t) obj->getNext()); Serial.flush();
+    Serial.printf("%s is at %08X (%08X); route: %08X",obj->name,(uint32_t) obj,(uint32_t) obj->sibling,(uint32_t) obj->getNext()); Serial.flush();
     if (NULL != grp)
     {
       Serial.printf("; group: %08X\n",(uint32_t) grp); Serial.flush();