Imagine that I have a shape that has some tight, intricate
curves. Just for simplicity, something in the shape of the letter
"S". What I need to do is have a fill start from one end of the S
and follow that shape to the end, so the new color grows along the
path, oriented to the shape of the path. In essence, the shape will
"grow" from nothingness into its full form. It's very similar to
using sweep nurbs in Cinema 4D, if that helps.
I tried using a mask but I don't know how to make it
"follow" the curves of the S. Can somebody please show me the best
way to do that? Tutorial? Is it a script thing?
the 'easiest' method for you to do this may be to simply use
mask and the timeline - although you will have to basically 'hand'
keyframe each object. one could 'dynamically' create a mask from
script, but it may just be simpler for you to build them by hand
depending on your design and object quantity.
make a copy of the object and 'paste in place' on a layer
above the original - now decide the 'time' you want this to take
place in and convert the entire span (of the new 'mask' object
layer) to keyframes. then starting at the 'second to last' keyframe
begin erasing portions of it in each frame in increments that will
result in no mask being present by the time you reach frame one.
then right-click the layer and designate it as a mask.