Re[2]: [Gnash-dev] Re: gotoAndPlay bug in Gnash

[Udo Giacomozzi]

Hello Martin,

Wednesday, May 9, 2007, 5:40:22 PM, you wrote:
MG> In that case maybe neither should we, and dump the advance/retreat control.
MG> It's a bit like asking for a rewindable computer game... unless
MG> someone can figure out what it means to rewind a flash movie.
MG> For deterministic, non-interactive animations I understand the
MG> concept, but not in general.

We do know some if not most details. I posted some information in
other posts of this thread (yes, we should add them to the Wiki).

Rewind a movie means (much simplified): restore the state of all
originally *static* instances in that frame. Instances that have been
modified by a script or created dynamically must be treat differently.

We have two levels of deterministic information:

- lifetime of an instance (when if first appears on stage until it is
  removed): this will always restored when rewinding

- changes in matrix and color transform: only restored when not
  modified by ActionScript

Instances that have been *created* dynamically (attachMovie() and
friends) are not touched when rewinding.

It's difficult to abstract this since the MM player makes lots of
exceptions...

Udo