Changing the length of a line over time based off external data

[Scott Mcgee]

So there’s 2 ways you could do this. (Haven’t tested these. So you may have to tweak if they don’t work)

If your Json was to look like this.

“One” : 0,
“Two” : 50,
“Three” : 100,
“Four” : 10

First way allows to change timings based on keyframes. So set up your keyframes and add the below expression to the element you wish to animate.

txt = footage(“Country.json”).sourceData;

Key(1).value = txt.One;
Key(2).value = txt.Two;
Key(3).value = txt.Three;
Key(4).value = txt.Four;

Alternatively you can (found this on rocketstock. Again not tested)

a = txt.One;
b = txt.Two;
c = txt.Three;
d = txt.Four;

ease(time,inPoint,inPoint+1,[a],[b]) + ease(time,inPoint+1,inPoint+2,[b],[c]) + ease(time,inPoint+2,inPoint+3,[c],[d]);

Hopefully one of those does the trick for you.

[Angela Ravi]

Thanks a lot Scott McGee. I used another method to get it to work from one of the previous answers posted on here. I’d already tried the ease method previously but couldn’t get it to work. So I used this method suggested by Oleg Pirogov from 2 weeks before for another user..

$.evalFile(‘PUT_YOUR_JSON_FILE_PATH_HERE’);

var dur = 0;

for (var i=0, len = arr.length; i=time) break;
}

i === len || i === len-1 ? arr[len-1].slider : linear(time, dur-arr[i].duration, dur, arr[i].slider, arr[i+1].slider);

(Jason file will be like below)
var arr = [{“ID”: 1, “slider”: 1000, “duration”: 4}, {“ID”: 2, “slider”:2000, “duration”: 4}, {“ID”: 3, “slider”: 3000, “duration”: 4}];

I applied this to the width property of the line/rectangle and it works.

[Scott Mcgee]

No problem,

Just because I’ve had a chance to test them. The ease expression didn’t work how I thought it would. So as an alternative. I’m recorrecting the method just incase anyone tries it and fails.

txt = footage(“Test.json”).sourceData;

a = txt.One;
b = txt.Two;
c = txt.Three;
d = txt.Four;

if (time < 1){
linear(time,inPoint,inPoint+1,a,b)
}else if (time < 2){
linear(time,inPoint+1,inPoint+2,b,c)
}else linear(time,inPoint+2,inPoint+3,c,d);

Looking at the expression you’ve posted, it just makes it tidier to for loop through. So you don’t have to keep writing else if, for when you have 20 linear(time,t1,t2,v1,v2) expressions. Glad you found that I was struggling to find a for loop which will come in handy myself. 🙂