ROM hacking: Difference between revisions

Revision as of 11:51, 2 April 2025

Revision as of 11:52, 2 April 2025

Line 60:

As many Game Boy Advance games use the M4A Engine (informally called "Sappy Driver" and officially known as "MusicPlayer2000" or MP2k) for music, the program SapTapper can be used to hack Game Boy Advance music data. Various other utilities were created to work with the engine such as [https://web.archive.org/web/20160306150654/http://www.pokemonhackersonline.com/showthread.php?t=120-Wataru-Kun-s-Ultimate-Pok-mon-Music-Hacking-Guide Sappy 2006]. Another instance of the same engine being used between games is on the Nintendo 64 where most games use the same format; albeit with different sound banks for each game. A utility known as the [https://github.com/jombo23/N64-Tools/tree/master/N64MidiTool N64 Midi Tool] was created to edit the sequences that the majority of Nintendo 64 games use, however it does not cover first-party N64 titles that use a slightly different engine such as ''[[Super Mario 64]]''.

On the Sega Mega Drive (Genesis), several games made for the system had its music and sound effects created under a single sound engine commonly known as "SMPS" (also known as "Sound-Source" by some developers), which has been offered in both [[Motorola 68000|68000]] and [[Zilog Z80|Z80]]-based versions.<ref>{{cite web|url=https://vgmpf.com/Wiki/index.php?title=Mega_Drive/Genesis_Sound_Driver_List#Sega|title=Mega Drive/Genesis Sound Driver List|website=Video Game Music Preservation Foundation}}</ref><ref name="smps">{{cite web|url=http://segaretro.org/SMPS|title=SMPS|website=Sega Retro}}</ref> This sound engine, leveraging both the [[YM2612]] and [[SN76489]] sound chips of the console, was predominantly used in a wide variety of Japanese-developed games for the system (including Sega's first-party games),<ref name="smps" /> with some games providing modified versions of the sound engine tailored to a specific game. The SMPS engine has been researched for decades by many hackers,<ref>{{cite web|url=http://forums.sonicretro.org/index.php?showtopic=32473|title=Valley Bell's SMPS Research|website=Sonic and Sega Retro Message Board|date=December 31, 2013}}</ref> which led to the creation of various utilities<ref>{{cite web|url=http://info.sonicretro.org/Sonic_Hacking_Utilities#Sound_Editors|title=Sonic Hacking Utilities|website=Sonic Retro}}</ref> that can alter and create music (and sound effects) for games using the SMPS engine (most notably the ''Sonic the Hedgehog'' games in particular); many of the compositions and arrangements made under the SMPS engine had eventually made their way onto the [[Steam Workshop]].<ref name="steamworkshopsmd">{{cite web|url=http://steamcommunity.com/workshop/about/?appid=34270|title=Steam Workshop :: SEGA Mega Drive & Genesis Classics|website=steamcommunity.com}}</ref>

===ROM expansion===

Line 73:

The main purpose of distributing a hack in patch form is to avoid the legal aspects of distributing entire ROM images; the patch records only what has ''changed'' in the ROM, hence distributing it does not usually distribute parts of the original game. {{Citation needed span|date=September 2024|reason=A claim of legality without source|In this context, the patches typically contained user-made code changes to the original game and not the game’s complete copyrighted code, which would have eliminated any copyright issues that may occur with distributing unofficial patches for games.}} A patch is also normally drastically smaller than a full ROM image (an NES ROM can run anywhere from 8&nbsp;KB to 2&nbsp;MB; a Super NES ROM can run from 256&nbsp;KB to 6&nbsp;MB; and Mega Drive (Genesis) ROMs can run from 512&nbsp;KB to 4&nbsp;MB).

In a novel example of legal distribution, Sega released a [[Steam (service)|Steam]]-based virtual hub for its previous collection of Mega Drive (Genesis) games, entitled ''[[Sega Mega Drive Classic Collection#Sega Mega Drive Classics Hub|Sega Mega Drive Classics Hub]]''. The ''Hub'', besides allowing players to play emulated versions of these older games, takes advantage of Steam's support for user-created content through the Steam Workshop, officially allowing the distribution of ROM hacks of any of the offered games.<ref>{{cite web | url = http://www.eurogamer.net/articles/2016-04-29-modders-are-already-having-fun-with-sega-mega-drive-classics-on-steam | title = Modders are already having fun with Sega Mega Drive classics on Steam | first = Wesley | last = Yin-Poole | date = April 29, 2016 | access-date = May 3, 2016 | work = [[Eurogamer]] }}</ref><ref name="steamworkshopsmd" />

==Usage==