Sequencing Brush Strokes!?

[Dan Ebberts]

This is just pretty rough, and likely won’t meet your exact needs, but should give you an idea of possible automation. If you apply an expression like this to the End property of each brush’s Stroke Options:

tStart = inPoint;
dur = .75;
delay = .25;
t1 = tStart + delay*(thisProperty.propertyGroup(2).propertyIndex - 1);
t2 = t1 + dur;
linear(time,t1,t2,0,100)

It will sequence the brush strokes. Then, instead of adding the expressions by hand, you could use a simple script like this to apply the expression to each brush:

function addExpression(){
	var myComp = app.project.activeItem;
	if (! (myComp && myComp instanceof CompItem)){
		alert("No comp active.");
		return;
	}
	if (myComp.selectedLayers.length == 0){
		alert ("No Layer Selected.");
		return;
	}
	var myLayer = myComp.selectedLayers[0];
	var myEffects = myLayer.property("ADBE Effect Parade");
	var myPaint;
	var myStrokes;
	var myBrush;
	var expr = 'tStart = inPoint;\r' +
	'dur = .75;\r' +
	'delay = .25;\r' +
	't1 = tStart + delay*(thisProperty.propertyGroup(2).propertyIndex - 1);\r' +
	't2 = t1 + dur;\r' +
	'linear(time,t1,t2,0,100)\r';
	for (var i = 1; i <= myEffects.numProperties; i++){
		if (myEffects.property(i).matchName == "ADBE Paint"){
			myPaint = myEffects.property("ADBE Paint");
			myStrokes = myPaint.property("ADBE Paint Group");
			for (var i = 1; i <= myStrokes.numProperties; i ++){
				if (myStrokes.property(i).matchName == "ADBE Paint Atom"){
					myStrokes.property(i).property("ADBE Paint Properties").property("ADBE Paint End").expression = expr;
				}
			}
		}
	}
}
addExpression();

I hope that’s helpful.

[Miren Patel]

I hate you for making me realise I didn’t think about making an expression.

Thank you, you genius.

Tbf I wouldn’t have thought about “property index”

I tried the script, it seems to come up with an error, but the expression works absolutely fine, I have no problem doing ‘copy expression only’ – cmdA – cmdV

Thanks!!

[Miren Patel]

The only thing – putting this into practice, is that all the brush strokes animate on backward (in terms of when they were drawn) trying to figure out if there is a way to change the expression slightly so that it sequences them the other way around.

maybe finding the total number of propertyindex’s and then subtracting the property index with the total number to get a new number

[Dan Ebberts]

Yes, so probably like this:

tStart = inPoint;
dur = .75;
delay = .25;
t1 = tStart + delay*(thisProperty.propertyGroup(3).numProperties - thisProperty.propertyGroup(2).propertyIndex);
t2 = t1 + dur;
linear(time,t1,t2,0,100)

[Dan Ebberts]

Also, would love to know what error message you’re running into with the script.

[Miren Patel]

Hi Dan, sorry for late reply – this is the error

[Miren Patel]

This was the final expression I used:

haha I just realised reading through it, I have a very redundant “+1” and then “-1”

same as what you had basically but with the redundancy haha

tStart = inPoint;
dur = effect("Duration")("Slider");
delay = effect("Delay")("Slider");
totalStrokes = thisProperty.propertyGroup(3).numProperties;
reversedIndex = totalStrokes - thisProperty.propertyGroup(2).propertyIndex + 1;
t1 = tStart + delay * (reversedIndex - 1);
t2 = t1 + dur;
linear(time,t1,t2,0,100)