fceux: Record movie from power-up without battery deletion

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fceux: Record movie from power-up without battery deletion

Post by DRW » Wed May 23, 2018 2:36 pm

Is there a way in fceux to record a movie (i.e. recording the input for playback in the emulator, not recording an AVI file), starting from the power-up state, but with the battery save remaining intact?

As I see it, there are only two options:
Recording a movie from the start, which means that everything gets set back, including the battery save.
Recording a movie from "now" which means that it's an input file with a savestate at the beginning.

Some elaboration:

Let's say you have the following situation:

You're working on a game that has a battery save and you want people to test the game.
When they encounter a bug, you ask them to record a movie of the bug. This way, you can see where it happens. And by playing the movie over a new ROM, you can see whether your code changes actually fixed the bug.

But what happens if it's a huge game and the bug occurs in a later part of the game?

Then you don't want the tester to send you a video that plays for three hours until he reaches the bug.

And creating a video from a certain savestate in the game will help you in seeing the bug. But if you correct the bug and therefore your source code has changed, the video's savestate data might not work anymore on your new ROM since the internal code looks different.

So, the solution would be this:
Create a video from the console's power-up, but without resetting the battery save.
In this case, the player can save the game at a location near the buggy section. Then he can start recording, trigger the bug and send the video plus the sav file.
Then I can see the bug and correct it. And as long as my battery data structure hasn't changed, I can still load the video + sav with the new ROM and see whether the bug doesn't appear anymore.

So, is there any way to start an input record from power-up, without resetting the sav file and without creating an fceux savestate inside the input record?
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Re: fceux: Record movie from power-up without battery deleti

Post by Sour » Wed May 23, 2018 4:46 pm

As far as I know, FCEUX doesn't let you do this (but I could be wrong)
Both Bizhawk & Mesen do have that option (recording from power on, with battery data), though.

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