Progressive wiggle – still having issues! FAO Dan!

[Nico Jones]

Hi there,

I’m still having difficulty in getting a smooth move between wiggle frequency keyframes. I used to get a frantic wiggle between the keyframes when AE recalculated the location on each frame, and then Dan gave me this expression…

freq = thisComp.layer(“Wiggle Control Sliders”).effect(“FREQUENCY”)(“Slider”);
amp = thisComp.layer(“Wiggle Control Sliders”).effect(“AMOUNT”)(“Slider”);

if (freq.numKeys > 0){
accum = 0;
v0 = freq.valueAtTime(0);
t0 = 0;
i = 1;
while (i <= freq.numKeys){ t = freq.key(i).time; if (t < time){ accum += (v0 + freq.key(i).value)*(t - t0)/2; v0 = freq.key(i).value; t0 = t; if (i == freq.numKeys){ accum += (time - t0)*v0; } }else{ accum += (freq + v0)*(time - t0)/2; break; } i++; } }else{ accum = freq*time; } wiggle(1,amp,1,.5,accum); ...which seemed to work at his end but not mine - I get a big movement jerk after the last keyframe. Here is a project file with the expression applied, and the problem frame marked. I'm working in CS3 if that makes a difference. Does this work with you Dan/anybody else? I really need to solve this problem if at all possible 🙂 https://webfilemanager.co.uk/dsf.php?fileid=GVkRrPyu

Many thanks,

nico

[Filip Vandueren]

Both the code and your project work fine for me.

[Nico Jones]

Ack. That’s not good. Are you on CS5? CS4? Thanks for having a look!

Nico J BB

[Filip Vandueren]

Checked in CS4 it worked, just checked in CS3 it’s broken.

However, this does seem to work, and is even more correct IMHO


freq = thisComp.layer("Wiggle Control Sliders").effect("FREQUENCY")("Slider");
amp = thisComp.layer("Wiggle Control Sliders").effect("AMOUNT")("Slider");

if (freq.numKeys > 0){
accum = 0;
for (t=0;t<=time;t+=thisComp.frameDuration) { accum+=freq.valueAtTime(t) } accum*=thisComp.frameDuration; }else{ accum = freq*time; } wiggle(1,amp,1,.5,accum);

I'm not sure why Dan chose to do a kind of linear interpolation between the keyframes himself (one reason would be because there are fewer calculations), because it doesn't take in account any seasing you may but on the keyframes of Slider Control.
The downside of my solution is it uses a lot more calculations (one per passed frame) whereas Dan's only uses one per passed keyframe, so this could get slow on very long compositions.

Also, I'm scratching my head why the original doesn't work in CS3 and does in later versions

[Dan Ebberts]

Here’s a different approach that might work for you.

freq = thisComp.layer("Wiggle Control Sliders").effect("FREQUENCY")("Slider");
amp = thisComp.layer("Wiggle Control Sliders").effect("AMOUNT")("Slider");

if (freq.numKeys > 0){
if (time &lt= freq.key(1).time || time &gt= freq.key(freq.numKeys).time)
wiggle(freq,amp)
else{
n = freq.nearestKey(time).index;
if (freq.key(n).time > time) n--;
f1 = freq.key(n).value;
f2 = freq.key(n+1).value;
t1 = freq.key(n).time;
t2 = freq.key(n+1).time;
w1 = wiggle(f1,amp);
w2 = wiggle(f2,amp);
linear(time,t1,t2,w1,w2);
}
}else{
wiggle(freq,amp)
}


I had to do some HTML manipulation to get this code to post correctly – hopefully I got everything.

Dan

[Nico Jones]

Looks like that’s done it! Thanks so much for sticking with it guys – it’s a crucial part of a music vid I’m working on and it’s really, really helped me out.

nj

Nico J BB

[Nico Jones]

How can I amend this expression so that I can apply it straight onto the position of a 3D object and have it only affect X+Y, not Z? I’m having weird issues when I try to split them…

freq = thisComp.layer(“Wiggle Control Sliders”).effect(“FREQUENCY”)(“Slider”);
amp = thisComp.layer(“Wiggle Control Sliders”).effect(“AMOUNT”)(“Slider”);

if (freq.numKeys > 0){
if (time <= freq.key(1).time || time >= freq.key(freq.numKeys).time)
wiggle(freq,amp)
else{
n = freq.nearestKey(time).index;
if (freq.key(n).time > time) n–;
f1 = freq.key(n).value;
f2 = freq.key(n+1).value;
t1 = freq.key(n).time;
t2 = freq.key(n+1).time;
w1 = wiggle(f1,amp);
w2 = wiggle(f2,amp);
linear(time,t1,t2,w1,w2);
}
}else{
wiggle(freq,amp)
}

Nico J BB

[Dan Ebberts]

Like this:

freq = thisComp.layer("Wiggle Control Sliders").effect("FREQUENCY")("Slider");
amp = thisComp.layer("Wiggle Control Sliders").effect("AMOUNT")("Slider");

if (freq.numKeys > 0){
if (time <= freq.key(1).time || time >= freq.key(freq.numKeys).time)
wiggle(freq,amp)
else{
n = freq.nearestKey(time).index;
if (freq.key(n).time > time) n--;
f1 = freq.key(n).value;
f2 = freq.key(n+1).value;
t1 = freq.key(n).time;
t2 = freq.key(n+1).time;
w1 = wiggle(f1,amp);
w2 = wiggle(f2,amp);
w = linear(time,t1,t2,w1,w2);
[w[0],w[1],value[2]]
}
}else{
w = wiggle(freq,amp);
[w[0],w[1],value[2]]
}

Dan

[Nico Jones]

Fan-flipping-tastic. Thanks!

Nico J BB

[Steve Roberts]

Thanks, Filip and Dan. Your expressions helped me out on my current project.