I've been out of AE for a while now and just trying to do an effect that I think should be straightforward but I can't work it out! I've googled around but still can't find the solution.
Basically, I have a mask that starts as one shape and then changes to another shape ... say, square to circle. This part is OK.
But I want to a layer duplicated many times along the path so that it is a path made up of little images. Then when the mask is animated the layers all move with it. Something like the vegas effect but a layer instead of the dashes.