How to turn off and on an expression randomly

[Andrei Popa]

You could try to multiply the random expression with 3,4 so it is enabled/disabled 3,4 seconds.

Andrei

[Daniel Walker]

Hi Andrei thanks for the reply, could you show me how would it look. Thanks.

[Andrei Popa]

Hey Daniel. I thought you had a random enable/disable expression and it was hapening too often. Wll, in case you don’t, something you can try is
modulusSeven = Math.round(time%7);
if(modulusSeven <= 3 ){
//your expression here
}
else value;
This will enable the expression for 3.5 seconds, and then disable it 3.5 and so on. I think you could play with the 7 and 3 numbers so you can get something that seems random.

Andrei

[Daniel Walker]

Thank you so much for that, you are a magician. Thanks a million Andrei Popa .

[Daniel Walker]

it is working good but the only thing now is that it is staying 3 sec withe effect on the scale expression and like a fraction on the normal state of the scale . How can i put a time or more duration for the normal state of the scale.

[Daniel Walker]

Awesome !!! I added this at the end of value and that added more time to the initial state and it is working, I know there may be a better solution but so far i can go with this thanks a lot Andrei Popa

modulusSeven = Math.round(time%7);
if(modulusSeven <= 5 )
{
minAudio = 0;
maxAudio = 100;
minStretch = 100;
maxStretch = 125;
audioLev = thisComp.layer("Sound Key 2").effect("Sound Keys")("Output 1");
s = linear(audioLev, minAudio, maxAudio, minStretch, maxStretch);
[s,s,s];
//your expression here
}
else value + modulusSeven;

[Daniel Walker]

Well still not working that Well, still too short the time , any Help with this guys?

[Andrei Popa]

You could add 2 “Slider Control” controls to this layer. Name them “Cycle duration” and “Expression duration”. The expression then for this would be:
modValue = Math.floor(time%effect("Cycle duration")("Slider"));
if(modValue < effect("Expression duration")("Slider") ){
minAudio = 0;
maxAudio = 100;
minStretch = 100;
maxStretch = 125;
audioLev = thisComp.layer("Audio Amplitude").effect("Both Channels")("Slider");
s = linear(audioLev, minAudio, maxAudio, minStretch, maxStretch);
[s,s,s];
}
else value;
So the time that the layers stays still is “Cycle duration” minus “Expression duration”. Play with this 2 until you get something you like(Expression duration should always be smaller than Cycle duration). If, for example, you set them to be 15 and 9, the layer will scale up and down 9 seconds and then stay still until it reaches 15 seconds, and start moving again. If you add the modValue to the value at the end, you make the layer grow a bit each second.

Andrei