Take a look at this topic Create a curved plane surface which dynamically changes its size and posts from @hofk there.
Gonna make a new thread for this.
Is there a demo?
Csg dynamically subtracted? Does it not get stuck?
Are you trying to create a trail behind your object? If so - there are better ways to do that.
Something like this?
We tried several approaches (realtime geometry creation / manipulation) to solve a similar problem - at least I believe it’s similar the logo-animation on our freshly released (micro)website https://cream.gmbh (we’ll showcase it here in the discourse soon).
The only thing that performed smooth enough for a complex geometry such as our curvy logo (especially on mobile devices), was animating the transparent material’s alpha-map.
use localClipping can growing animation
Did you use a VideoTexture for the alpha map?
That is a good solution. With the proper setup of alphaMap and geometry UVs (crammed together in one half of the [0,1] interval on either U or V, I guess), the only update you have to do during animation is a single uniform, which will be updated anyway as a consequence of the presence of a texture (actually, the texture and associated uniforms must also be considered costs of this method).
Is there not something called morphtargets that would be good to mention here.
Otherwise you need a procedural way to regenerate the mesh per frame or pre-generate the mesh data for switching to per-frame.