interpolate parameter / adjust rate of change – without keyframes

[Dirk De jong]

I’ve only ever used expressions at a basic level but after messing with it a bit it seems that variables don’t maintain their values from frame to frame so perhaps even setting a param up to continually increment or decrement (without keyframes) is not currently possible with expressions – so the answer to my earlier question is probably “no.”

I wouldn’t be disappointed to find out I’m somehow wrong about that though : )

I was halfway thinking I had done this before but now I think I am misremembering it and what I was thinking of is a parameter behavior in Apple Motion called “Rate” which allows for doing this

[Dan Ebberts]

This may be helpful:

https://motionscript.com/articles/speed-control.html

If you’re not discouraged after reading it, come back. ☺

Dan

[Dirk De jong]

[Dan Ebberts] “This may be helpful:
https://motionscript.com/articles/speed-control.html“

Very helpful indeed – thanks a lot. For my relatively simple case (of wanting the Noise evolution to progress in a linear way without keyframes with some control over how fast it progresses) simply taking the first expression on the page you referred me to

spd = 360;
value + time*spd

and in the place where the 360 is changing it to point toward my expression control

spd = (thisComp.layer(“Null 1”).effect(“Slider Control”)(1));
value + time*spd

basically gives me what I was after – reading the article further and playing around with key framing the speed I see that it gets a little more complicated – but I can definitely work with this – thanks again