finding the current beat position in a script

Okay, here's my issue. I have this script (below) that calculates every half beat and adds "swing" to any notes falling there. The trouble is, the beat position isn't always accurate. I found a partial solution in this thread (viewtopic.php?t=128908), which seemed to work at first, but the values are all thrown off when a different track is selected. Help! What's the best way to find the current position so I can detect notes falling on half beats?

PluginParameters = [{name: 'Swing %', minValue: 0, maxValue: 30, numberOfSteps: 60, defaultValue: 20},];

NeedsTimingInfo = true;
var beat = 0; 

function HandleMIDI (e) {
 		if (e instanceof NoteOn) {
 		  	var delay = GetParameter('Swing %')/100;
 	  		processNoteOn(e, delay);
 	  } else {
 	  		e.send();
 	  }
}

function processNoteOn(e, delay) {
if (isSwingPosition() && delay > 0) {   
	e.sendAfterBeats(delay);
} else {
	e.send();
}
}

function isSwingPosition() {
Trace('BEAT: ' + beat);
return beat.toString().slice(-2) == '.5';
}

function ProcessMIDI () {
var info = GetTimingInfo();
var curr = Math.ceil(info.blockStartBeat * 24) / 24;
if (info.playing && beat !== curr) beat = curr;
}

Try this:

PluginParameters = [{type: "lin", name: 'Swing %', minValue: 0, maxValue: 30, numberOfSteps: 60, defaultValue: 20},];

NeedsTimingInfo = true;

function HandleMIDI (e) {
   if (e instanceof NoteOn) {
      var delay = GetParameter('Swing %')/100;
      processNoteOn(e, delay);
   }
   else {
       e.send();
   }
}

function processNoteOn(e, delay) {
  if (isSwingPosition(e) && delay > 0) {   
     e.sendAfterBeats(delay);
  }
  else {
     e.send();
  }
}

function isSwingPosition(e) {
  var fraction = e.beatPos - Math.trunc(e.beatPos);
  // check to see if event is within a range close to .5
  if (fraction > .45 && fraction < .55) {
      return true;
  }
  else {
      return false;
  }
}

Also, you need to take care of the NoteOff's. Right now, your NoteOff's are not delayed...so the swung notes will be shorter duration. And if you ever set the swing to a large enough delay that the note off comes before the note on...then you will end up with hung notes...

Try this:

 

PluginParameters = [{type: "lin", name: 'Swing %', minValue: 0, maxValue: 30, numberOfSteps: 60, defaultValue: 20},];

NeedsTimingInfo = true;

function HandleMIDI (e) {
   if (e instanceof NoteOn) {
      var delay = GetParameter('Swing %')/100;
      processNoteOn(e, delay);
   }
   else {
       e.send();
   }
}

function processNoteOn(e, delay) {
  if (isSwingPosition(e) && delay > 0) {   
     e.sendAfterBeats(delay);
  }
  else {
     e.send();
  }
}

function isSwingPosition(e) {
  var fraction = e.beatPos - Math.trunc(e.beatPos);
  // check to see if event is within a range close to .5
  if (fraction > .45 && fraction < .55) {
      return true;
  }
  else {
      return false;
  }
}

 

Also, you need to take care of the NoteOff's. Right now, your NoteOff's are not delayed...so the swung notes will be shorter duration. And if you ever set the swing to a large enough delay that the note off comes before the note on...then you will end up with hung notes...

Aha, the beatPos property is what I was looking for! I actually have a compensator for the NoteOffs in the full version, I just cut it down so you didn't have to dig through it for the relevant parts. Thanks much.