Possible to hack GBA game brightness/color/contrast?

Discussion in 'GBA - Game Development, ROM Hacks and Translations' started by granville, Jun 21, 2008.

  1. granville
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    granville GBAtemp Goat

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    A big problem with many gba games (especially early ones and ports of old games) is that the games are too bright. In our day and age of DS Lites, better SP screens, and other such things, a game can appear as dark as it wants and still show up well enough. My question is this:

    Can you hack a GBA rom to change the game's graphics to a lighter/darker tone (as well as the gamma, contrast, and color saturation levels)?

    Example:

    This
    [​IMG]

    To this:
    [​IMG]

    If so, how?
     
  2. tomqman

    tomqman This Is Everyone's Fault But Mine.

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    you could tint a ds screen pertector. and pop it on when ur playing gba
     
  3. granville
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    granville GBAtemp Goat

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    I guess that's one way to do it, but I wanted to hack the actual rom file.
     
  4. FAST6191

    FAST6191 Techromancer

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    GBA colours are BGR (I am not aware of any games that use the undocumented register: http://nocash.emubase.de/gbatek.htm#gbalcdvideocontroller ) and brightness contrast is achieved by tricks with colours (ostensibly for the early GBAs as you mention) and in game options either cycle through multiple palettes (not so common) or tweak them "numerically" (more common).

    From here you want a palette hack:
    http://etk.scener.org/?op=showtutorial&st=3
    and make sure to read:
    http://nocash.emubase.de/gbatek.htm#lcdcolorpalettes

    See also the rom hacking docs in my signature on DS icons as the GBA and DS share the same principles.
    As palettes are loading into the memory you could possible even make an AR code for basic hacks and alter the games that tweak palettes to more or less extreme levels (there will usually be a byte somewhere detailing what level of tweaking to do).
     
  5. granville
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    granville GBAtemp Goat

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    Thanks for the info! I'm not very experienced in hacking, but I'll look at this and try it out. What I was hoping for was some kind of way to just darken the entire game without having to individually hack pallets for objects. Oh well.
     
  6. spinal_cord

    spinal_cord Knows his stuff

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    IF yourusing a DS, why not just turn the light setting down a bit?
     
  7. granville
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    granville GBAtemp Goat

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    It's the actual colors and contrast levels that I'd like to adjust, not the brightness.
     
  8. Frederica Bernkastel

    Frederica Bernkastel WebPerf and PWA advocate; @antoligy on Twitter

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    Rom extractor and a photo editor thats the hard way.
    Only do it my way if your stupid like me.
     
  9. gukid

    gukid Advanced Member

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    I'm gonna have to give this a try as well. Some games that really suffered during this "turning point" of the GBA were ALL of the Blizzard games (Blackthorne looks especially horrible) and the Breath of Fire games. I'd love to tone the colours in BoF2 down to what they were like in the SNES version and rewrite the script for that game. Such a great game... but the storyline just doesn't make any sense with the hackjob of a translation it got...