Vobs

[Rauli Ruohonen <rruohone@xxxxxxxxxxxx>]

We had a meeting today, and discussed about Vob's (again). This time we
discussed at a rather abstract level, and that resulted in some changes.
(just some minor cleanup)

Tuomas described indexes as follows:

  Index: Vob * {Vob} --> {Vob}
  Index(x, S1) = S2  ==>   S2 is a subset of S1
  Index(x, Index(x, S)) = Index(x, S)

So that Index(v, S) = {x | such x \in S that is related to v in some way}.

There is a stack of indexes in the ZZ system:

  1. Key equality index. Determines which vobs have the same key.
  2. Span index. Determines which vobs have overlapping spans with this one.
  (3. Clone index?)

Interpolation is not done in VobScene, but in some Interpolator or
whatever that tells the VobScenes what to do. Hooks in the Interpolator
determine which Vobs they control in the VobScenes-to-be-interpolated 
(according to a priority order). They will also tell the Interpolator
what to do to the Vobs they control.

Tuomas will write to the Vob article about this. (but sadly, not too
mathematically..)