How hard would it be to isolate SMB2 in mario all stars?

[Ar8temis008]

I have never hacked any game before, so I thought this might be a good place to start. All I want to do is remove SMB1, LL, and SMB3 so when I start the game it automatically boots into SMB2. I also want to have the "save menu" appear after the SMB2 title screen before you select a character. Last but not least, I want to have between level saving instead of between world. Is this possible and feasible for someone new to rom hacking?

[KingMike]

All of that sounds like very advanced hacking. Definitely requiring ASM skills.

[Ar8temis008]

All of that sounds like very advanced hacking. Definitely requiring ASM skills.

Would it be easier to just add a save feature to NES SMB2?
I don't want anything complicated, just an option to quit the game and return later without save states.

[Disch]

In general, if you have to ask how hard something is going to be, the answer is "very hard".  The only hacking jobs that are easy are the ones where you already have an idea of how to do it.



For SMB2 NES.... adding a menu option means changing drawing routines, input routines, and actually adding the save.

For All-Stars, isolating a single game would be mostly just finding the SMB2 entry point and jumping to it earlier.  The change would be incredibly easy, but finding where to make that change would be very rough.  Best approach I know of is to dump a tracelog and pour over it.... and... well.... looking at pages of undocumented asm code is hard enough, but when you're a noob you don't even really know what you're looking for.... so you'll just be staring into space.

Modifying All-Stars would definitely be easier, but that's only relative to the NES hack.  I'm not sure I'd recommend either of these as a beginner project.

[Ar8temis008]

Turns out this was already sort of done. Someone had the brilliant idea of replacing the characters in OG Doki Doki Panic with Mario characters which already included a save feature, Nintendo just redacted it for some reason.

[justin3009]

I've 'technically' isolated SMB2 in All-Stars on the SNES.  I posted a beta patch of that in my SMB2 project thread in the Personal Projects section.  There's a couple bugs I'm pretty sure left over but no one went into depth on what was buggy or not.

There was no selectable save or anything yet.  I was hoping to add things like that much later on down the road after the basis of the project was ready.

[KingMike]

Turns out this was already sort of done. Someone had the brilliant idea of replacing the characters in OG Doki Doki Panic with Mario characters which already included a save feature, Nintendo just redacted it for some reason.

Licensing. The Doki Doki characters were a part of some sort of Japanese festival, so once that was over Nintendo modified the game to use Mario characters to avoid additional licensing need.
The game was reworked to remove the save function almost certainly because adding a save feature to a cartridge costs them extra money (whereas on a disk, it did not).

[Ar8temis008]

I've 'technically' isolated SMB2 in All-Stars on the SNES.  I posted a beta patch of that in my SMB2 project thread in the Personal Projects section.  There's a couple bugs I'm pretty sure left over but no one went into depth on what was buggy or not.

There was no selectable save or anything yet.  I was hoping to add things like that much later on down the road after the basis of the project was ready.

I checked the thread, but I didn't see a download. Heh, it turns out that was what got me interested in this. Was it cancelled?

[justin3009]

Well, I definitely have a 'solo' one I think but there's bound to be some bugs.  I've already found one right off the bat.  The PC Lives are set to FF (255) instead of 05 like it should be.  I'll upload it as is though.  See if anyone can note any other bugs on the solo version so I can get it out of the way.  Once all bugs are fixed, I'll slap up another patch for a FastROM version.

No-Intro Name: Super Mario All-Stars (USA)
(No-Intro version  20130701-030720)
ROM/File SHA-1: C05817C5B7DF2FBFE631563E0B37237156A8F6B6

Requires an UNHEADERED SMAS ROM.

http://www70.zippyshare.com/v/dzgsQ13H/file.html - Here's the link to a 'solo' SMB2 patch.  I'm sure there's bugs and various code left overs from the other Mario games in the data somewhere.  I just got rid of a majority of the data.

Nope, project wasn't cancelled.  It's just currently on the back burner with numerous other projects I have.  I tend to bounce around at random points with the projects and do major updates then they go to sleep for a bit.

[Ar8temis008]

How much time would it take if I added a save mechanic myself? All I want is the regular save mechanic, nothing special and since it was already implemented in the og all-stars it doesn't sound too difficult.