Support for large Neo Geo ROM hacks?

protogem
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Support for large Neo Geo ROM hacks?

Unread post by protogem »

There are some feature rich rom hacks with much larger size than most(any?) official game, but that fit into 128MB - for instance KOF98AE which adds content from The Taito Type X/PS2/Steam upgrade of King of Fighters 98 (more characters, music, etc):

https://youtu.be/pCsoCWuXlik?t=6

Currently roms like this are partially playable on the core with some drawbacks, this one in particular has graphic and sound glitches.

I would not prioritize this over any bug fixing by any means, but it would be interesting to see it implemented in the future.
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darksakul
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Re: Support for large Neo Geo ROM hacks?

Unread post by darksakul »

Was the hack work intended for Real hardware or just emulation ?
It is my great regret that we live in an age that is proud of machines that think and suspicious of people who try to.
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Re: Support for large Neo Geo ROM hacks?

Unread post by Lisko »

From the fact that large homebrew rom like bad apple demo works fine, I think that the problem isn't in large rom support but in the hack and/or core inaccuracy somewhere. Have anyone tried these hacks using the neosd or darksoft on original hardware?
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aberu
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Re: Support for large Neo Geo ROM hacks?

Unread post by aberu »

If it doesn't work on original hardware, it's kinda moot if it doesn't work on the MiSTer core.

What is the hash on the zip file for your kof98AE? I will probably test this later today just to confirm.

SHA1: 51F8DA78230E78B1B7C64C8900074C10FF08155D

SHA256: 7CA2FD43FFC3E9026498FD3BFCC2134B73C38E6B2C8DCA7B635E75BB31F7A4CE

This is what I have, just to make sure.

I will add that this is not a ROM in the darksoft pack, and the darksoft pack isn't all supported by the MiSTer either. if you check the everdrive pack there are @ suffixes which ones are MiSTer ready (not official, just often tested and carefully picked for the most part). There is a mister neo geo add on pack which has this suffix and everything I've tested from that works just fine. The darksoft pack does not have an @ sign next to it.
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Re: Support for large Neo Geo ROM hacks?

Unread post by GreyRogue »

I know for certain that there are issues with KOF2004SE. It was only relatively recently that the correct algorithm for encoding audio samples was determined (by Lord Nightmare, I think?). This meant that older ROM hacks used an incorrect algorithm that sounded correct in older versions of MAME, but will have clipping issues on real hardware (and also on MiSTer).
From a discord post of mine from November:
Just did a little experiment. After Rysha confirmed on real hardware that KOF2004SE has broken sound for Athena Down+Forward+B, I made a quick experiment. If you grab this: http://www.smspower.org/forums/11965-VG ... =200#67173 , you can convert broken samples to wav files. Then you can use this code: https://wiki.neogeodev.org/index.php?ti ... cs#ADPCM-A , to convert it into correctly encoded adpcm files. The Athena sound effect is at 0x55f600-5613ff. So if you convert that to wav, then to correct adpcm and paste it back, it will play correctly without distortion. Just tried it, and it seemed to work. Obviously it would be better if the original hackers fixed it, but if you're desperate, you can do it yourself.

I had hewhoisred run it in latest MAME (at the time), where the same audio issue was demonstrated.
https://www.youtube.com/watch?v=caWqRil ... e=youtu.be

Using the method above, the ROM can be fixed to sound correct in real hardware and on MiSTer and newer versions of MAME.
Eddyiori
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Re: Support for large Neo Geo ROM hacks?

Unread post by Eddyiori »

This is really promising, one game could use this to be less painfull.
It's Blazing Star voice for "BONUS" that's so annoying that I play hardly that game.
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