I think the best option would be using “motion blur” layer, but I can’t control the decay or transparency. I used the constant subsampling type and I’m so close to get what I need but as I can’t control the decay.
I found a workaround but make the animation rendering so slow: if I use a “duplicate” layer on top of the motion blur and set the copies (“To”) up to 50 then I get the opaque effect I need but, as said, it’s not very smart…
I would like to control the number of “subsamples” and their separation. The motion blur layer is perfect for this task but as I can’t control the transparency I need to “hack” it by duplicating the layer as many times as needed to get an opaque result (I automate it with the “duplication layer” but I said it makes rendering so slow).
I linked the group layer to the spline, opened the transformation parameter of the group layer and converted the amount parameter to add and then linked the index of the duplicate layer to the addition sub-parameter of the converted amount parameter. That’s it.
I’ve been playing with your workaround, it works but it doesn’t behave like a real trail, for instance, in my example the star goes forth and back and the “subsampled stars” follow what the parent star did. In your solution, it doesn’t. It’s also pretty hard to make it work as you want so, in the end it makes easier to go back to my solution even if it increases the computer calculations to the moon, hehehe.
BTW, I’m going to suggest as a feature request to have the option to set the subsamples opacity when using “constant” subsampling type, I think it’s something that makes sense and I hope not hard to code.
Thanks @bjyitu, it looks like it’s the same approach as @Kai, it has the problem that you can’t make your object bounce from the last point of the path to the initial one. Look how my “example.sif” star moves from left to right and right to left, the subsamples always are behind the parent star.
Yes, I also made this option when playing with @Kai’s suggestion, but as said it’s not smart, hard to draw and animate… the best option is going to be the one with the new feature, it will allow to “echo” anything you want effortless and it will always follow any path or animation the parent does
This example you provided is heavy for computation because it is using Duplicate layer which has Motion Blur layer below it. Motion Blur is very slow, I avoid using it.
@bjyitu has already kinda found out the solution, here’s a modified version which may solve, your (@pablogil ) query. bjyitu your example for onion skinning didn’t use Time Offset parameter, using TimeOffset parameter you can create true onion skining and not worry about linking individual parameters to duplicate index value, just delay the animations using Time Offset parameter by connecting it to the Duplicate Layer’s index value. Some times things don’t work good with TimeOffset, Speed and Duplicate Layer (more)
I think type of interpolation is important here, also the time delay between “subsamples” also makes a significant impact, I believe your effect and shown by bjyitu are same, just different implementation of same thing. How you animate the shapes is also important.