rewind is a little weird with the new WIPs

rlbond · Post by **rlbond** » Fri Aug 12, 2005 4:32 pm

Has anyone else noticed that the rewind in the new wips (where you can set the rewind intervals) is a little different feeling? It seems that when I rewind, it goes back further than it should. It's especially noticable when I rewind (for example, if I died), and then need to rewind again (like, if I died for a second time), it seems to go back a lot further then.

I don't really know if it's a bug, but I was wondering if the programmers intended this.

kamaitachi · Post by **kamaitachi** » Sat Aug 13, 2005 2:26 am

Yes. I have experienced what you described. Also, most of the time rewind will only go back a split second, barely making a difference. My guess is that they tinkered with the threshold involved in determining whether to go back to the freshest rewind-state, or to go back to the second-to-last rewind-state, which it would do to prevent a rewind that doesn't go back far enough.

The Sage Of Time · Post by **The Sage Of Time** » Sat Aug 13, 2005 3:56 am

To my understanding.. Rewind works by ZSNES quietly taking savestates in the background every few intervals. When you hit the rewind key, it jumps to the last savestate it took. (Someone correct me if I'm wrong, which if so.. one could ignore the rest below.)

Because of this.. It's not too odd for rewind to "barely go back" when you use it. You just happened to hit the rewind key right after the specific interval passed, and the savestate to jump back to was only just saved. The same logic can be applied for it going back too far.. You end up hitting rewind right before the next interval comes up.

It is of course possible they adjusted the timing on when ZSNES captures these savestates, which may be why you notice the difference at all.. But it could just as well be coincidence.

rlbond · Post by **rlbond** » Sat Aug 13, 2005 4:28 am

yes, but it used to be that if you pressed rewind right after a new savestate was taken, it would go to the savestate before the one it just took.

Now it seems like it goes back more than two savestates instead. The result is that eventually you get to the last savestate and it "stutters" instead of just not rewinding at all.

kamaitachi · Post by **kamaitachi** » Sat Aug 13, 2005 6:01 pm

The Sage Of Time wrote:To my understanding.. Rewind works by ZSNES quietly taking savestates in the background every few intervals. When you hit the rewind key, it jumps to the last savestate it took. (Someone correct me if I'm wrong, which if so.. one could ignore the rest below.)

Because of this.. It's not too odd for rewind to "barely go back" when you use it. You just happened to hit the rewind key right after the specific interval passed, and the savestate to jump back to was only just saved. The same logic can be applied for it going back too far.. You end up hitting rewind right before the next interval comes up.

It is of course possible they adjusted the timing on when ZSNES captures these savestates, which may be why you notice the difference at all.. But it could just as well be coincidence.

That is my understanding as well, except for one thing. It seemed as though ZSNES was "intelligent" enough to not go back to a rewind-state that was saved only a fraction of a second before the rewind key is pressed. It would go back to the rewind-state before the most recent one, thus preventing the "stutter" phenomenon, in which it rewinds to a point only a split second before the key is pressed.

Post by **Nach** » Sat Aug 13, 2005 10:34 pm

I'll look into it.

Post by **grinvader** » Sun Aug 14, 2005 1:20 am

Nach wrote:I'll look into it.

No sweat.

To clear things for users: ZSNES has a delay after a rewind to check for ANOTHER rewind, in which case it jumps to the previous previous state.
Save state 1, 2, 3, rewind -> 3 then:
[time>delay], rewind -> 3
[time<delay], rewind -> 2

I have a way to make it nicer, taking speed throttle and frame advance stuff.