[Dan Ebberts]

Your code works fine for me.

[Dan Ebberts]

Yes, please report back if you find anything. I tried valueAtTime() with keyTime() and it didn’t help, but maybe you’ll figure something out.

[Dan Ebberts]

I get the same result. This looks like a bug to me. I’m not sure how you can work around it. (I’ve reported it to Adobe).

[Dan Ebberts]

<div>The script version would be like this:</div>

var myLayer = app.project.activeItem.layer(1);
var r = myLayer.sourceRectAtTime(0,false);
var myMask = myLayer.property("Masks").addProperty("Mask");
var myPath = myMask.property("Mask Path");
var myShape = myPath.value;
myShape.vertices = [[r.left,r.top],[r.left+r.width,r.top+r.height/5],[r.left,r.top+2*r.height/5],[r.left+r.width,r.top + 3*r.height/5],[r.left,r.top+4*r.height/5],[r.left+r.width,r.top+r.height]];
myShape.inTangents = [];
myShape.outTangents = [];
myShape.closed = false;
myPath.setValue(myShape);

Basically you’re just using the layer’s left, top, width, and height extents as provided by sourceRectAtTime() to calculate where you want the mask vertices to be. I just took a shot at it based on your diagram. Since the mask is all corner points, you can provide empty arrays for the in and out tangents.

[Dan Ebberts]

Do you mean “pingpong”? That would be like this I guess:

startMarkerTime = marker.key(1).time;
if (time <= startMarkerTime) {
  0;	
} else {
  t = time - startMarkerTime;
  t1 = key(1).time;
  t2 = key(2).time;
  d = t2 - t1;
  n = Math.floor(t/d);
  n % 2 ? t2 - t%d : t1 + t%d;
}

[Dan Ebberts]

Are you talking about scripting or expressions? With expressions you would just click on your vector layer with the pen tool to create a mask point and add an expression something like this to the Mask Path:

r= sourceRectAtTime(time,false);
p = [[r.left,r.top],[r.left+r.width,r.top+r.height/5],[r.left,r.top+2*r.height/5],[r.left+r.width,r.top + 3*r.height/5],[r.left,r.top+4*r.height/5],[r.left+r.width,r.top+r.height]];
createPath(p,[],[],false)

It would be similar but a little more involved with scripting.

[Dan Ebberts]

Probably close to this:

startMarkerTime = marker.key(1).time;
if (time <= startMarkerTime) {
    0;	
} else {
    (time - startMarkerTime)%(key(numKeys).time - key(1).time);
}

[Dan Ebberts]

I suspect you might have better luck if you were to post a keyframed mockup project of what this might look like. “shuffle around” is pretty vague…

[Dan Ebberts]

This is a simple example that will take the selected layers and randomly swap their positions. Might give you some ideas, or a place to start:

var myLayers = app.project.activeItem.selectedLayers;
var myPositions = [];
for (var i = 0; i < myLayers.length; i++){
	myPositions.push(myLayers[i].property("Position").value);
}
var temp;
var idx;
for (var i = 0; i < myPositions.length; i++){
	idx = i + Math.floor(generateRandomNumber()*(myPositions.length-i));
	temp = myPositions[i];
	myPositions[i] = myPositions[idx];
	myPositions[idx] = temp;
}
for (var i = 0; i < myLayers.length; i++){
	myLayers[i].property("Position").setValue(myPositions[i]);
}

[Dan Ebberts]

Try this:

thisLayer.content.numProperties