Opacity fade in and out with marks

[Dan Ebberts]

Something like this maybe:


fadeTime = .5;
if (marker.numKeys > 1){
t1 = marker.key(1).time;
t2 = marker.key(2).time;
if (time < (t1+t2)/2)
ease(time,t1,t1+fadeTime,0,100)
else
ease(time,t2-fadeTime,t2,100,0);
}else
value


Dan

[Marcelo Cabral]

Thank you Dan!! it works awesome. That was I was looking for. Best regards.

[Dan Ebberts]

edit: oops responding to wrong post.

Dan

[Marcelo Cabral]

Hi Dan, me again.
I have this expression to move in and out of the scene a text layer. It works fine but It would be even better with a ease in and ease out controls. Is this posible? Thanks in advance.

m = 450;
if (marker.numKeys > 0 && time <= marker.key(1).time){ value + [1,0]*(time-inPoint)*m; } if (marker.numKeys > 0 && time >= marker.key(1).time){
value + [1,0]*(marker.key(1).time-inPoint)*m + [0,0]*(time-marker.key(1).time)*m;
}
if (marker.numKeys > 1 && time >= marker.key(2).time){
value + [1,0]*(marker.key(1).time-inPoint)*m + [0,0]*(marker.key(2).time-marker.key(1).time)*m + [1,0]*(time-marker.key(2).time)*m;
}

[Mitch Mann]

Cool, I didn’t know you could do Eval’s in expressions, I’m going to try that. Thanks Dan!

[Dan Ebberts]

Hmmm… I think to do that the expression needs to be able to calculate the distance traveled over a specific interval, and then use ease(), easeIn(), or easeOut(), as appropriate. The way you have it set up, the expression could calculate the distance of the travel up to the first marker, but there’s no fixed distance traveled (or fixed interval) after the second marker–it just keeps going. Maybe with 3 markers…

Dan

[Juanluis Vich]

hi!
on your expression:


fadeTime = .5;
if (marker.numKeys > 1){
t1 = marker.key(1).time;
t2 = marker.key(2).time;
if (time < (t1+t2)/2)
ease(time,t1,t1+fadeTime,0,100)
else
ease(time,t2-fadeTime,t2,100,0);
}else
value


what if we add another “in” marker in the layer later in the timeline?
how it could be modified to have it fading in again? (so basically each time it reaches the “in” it fades in and “out” it fades out, not only the first time

thanks!

[Dan Ebberts]

Something like this might work:


fadeTime = .5;
if (marker.numKeys > 0){
n = marker.nearestKey(time).index;
if (time < marker.key(n).time) n--;
if (n > 0){
t0 = marker.key(n).time;
if (n%2)
ease(time,t0,t0+fadeTime,0,100)
else
ease(time,t0,t0+fadeTime,100,0);
}else{
0
}
}else
value


Dan

[Juanluis Vich]

awesome!!!

this way every marker will trigger the in and out fading, right? I don’t know if it is possible to make it work only if the comment “in” or “out” appears? to prevent any unwanted in/out, I mean…

[Dan Ebberts]

That’s trickier, especially if it’s possible that the expression could run into a marker that doesn’t have “in” or “out”. It would have to loop back through previous markers to figure out what state it should be in currently.

Dan