||Auxtools REALLY doesn't know how to handle filters as values;
when passed as arguments to auxtools-called procs, they aren't simply treated as nulls -
they don't even count towards the length of args.
For example, calling some_proc([a filter], foo, bar) from auxtools
is equivalent to calling some_proc(foo, bar). Thus, we can't use _animate directly on filters.
Use this to perform animation steps on a filter. Consecutive steps on the same filter can be
achieved by calling _animate with no target.|