Why do games have an alternative dol?

Discussion in 'Wii - Hacking' started by Jpaa, Jul 18, 2010.

  1. Jpaa
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    Jpaa Member

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    I'm not asking about the method to play alternative dols from an HDD, I'm asking about the very existence of an alternative dol in a game.

    Really, some games like SSX Blur has only the first screen in the main.dol, then it loads an alternative dol. Metal Slug Anthology plays the first five games just fine, then the sixth through an alternative dol. Metroid Prime Trilogy is totally segmented by alternative dols.

    What's the magic in the use of alternative dols? Does it bring any advantage to the game? Disc loading faster? Anything? Couldn't the games have only one dol and extinguish the need to reload?
     
  2. Dialexio

    Dialexio GBAtemp Advanced Maniac

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    It's meant to provide a slight hiccup for pirates. [​IMG]

    In all seriousness, it's probably to keep things separate and from conflicting with each other. Wii Sports Resort keeps all of the MotionPlus video crapola in one DOL, while the actual game stuff is deal with in another one. In the case of Metroid Prime Trilogy... Well, Metroid Prime 1, 2, and 3 were separate entities as-is, why bother with merging them together?

    It's not like this is a Wii-exclusive habit, either. When you install a program in Windows, it might be comprised of many EXEs and DLLs.
     
  3. Jpaa
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    Jpaa Member

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    It does make sense about Metroid Prime Trilogy, but SSX Blur is pretty dull. C'mon, can't you put the "don't destroy your things with the wiimote" screen in the same dol? All the other games do that. Metal Slug Anthology is also curious, since you use an alternative dol for one of its games, but not for the other five.

    I even thought about "organization", because of the sense MP Trilogy makes, but the SSX Blur case makes me think if there's some magic inside alternative dol, or if it brings money and good luck for the devs... It just... does little sense.
     
  4. smf

    smf GBAtemp Maniac

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    During development they wouldn't want to sit through that everytime. When they finished developing and needed to put it in, they might just have run out of memory.
     
  5. raulpica

    raulpica With your drill, thrust to the sky!

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    Or they were just lazy [​IMG]

    After all, as long as it works on an unmodified Wii, why should they care? They're free to do what they want [​IMG]
     
  6. Fishaman P

    Fishaman P Speedrunner

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    I think it's like a loader, where some DOLs have certain features, but break other features.
     
  7. fabi280

    fabi280 GBAtemp Regular

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    Isnt it related to IOS Reload?
    AFAIK it those alt .dols have been used to "block" it
     
  8. cwstjdenobs

    cwstjdenobs Sodomy non sapiens

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    Probably memory constraints and the anti piracy thing is a side effect seeing as games with multiple dols where out long before any loaders and every game isn't using it as a quick fix.

    The IOS reload happens when the dol is loaded. I guess the nintendo SDK does an IOS reload at the start like libogc used to.
     
  9. SifJar

    SifJar Not a pirate

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    I doubt alt. dols where designed specifically to hinder pirates. The idea has been in use on many consoles probably as long as there have been discs (I know PS2 definitely had multiple ELFs on some discs).

    I know on some games they're for the different parts. For example, on PS2 in a James Bond game there was a driving ELF, a shooting ELF and a menu ELF. Each may have been developed by a seperate team, compiled for testing and then stuck together on the disc, simpler than trying to combine them all into one binary.


    libogc doesn't anymore?
     
  10. DownSince86

    DownSince86 Advanced Member

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    I can answer this one.

    Metal Slug 6 was originally programed for the Atomiswave arcade platform where the rest of the games on that disc were originally programed for the Neo-Geo. So the reason they use a separate .dol in that game is due to the fact that they are emulating two entirely different machines.
     
  11. cwstjdenobs

    cwstjdenobs Sodomy non sapiens

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    No, if I remember rightly because it should be up to the app itself, but I can't remember if it was the latest release or the one before, and can't find the release notes anyhows. devkitpro.org is a mess...