Discussion in 'NDS - ROM Hacking and Translations' started by Xleet, Dec 21, 2008.

  1. Xleet

    Xleet Member

    Jul 18, 2008
    United States
    What are those overlay files that are in every DS rom? What are they for and how do you edit them? I havent had any luck with google on this one.
  2. FAST6191

    FAST6191 Techromancer

    pip Reporter
    Nov 21, 2005
    United Kingdom
    It has been done a few times but OK.

    In modern computers you have DLL files or similar that are loaded as needed. Older machines do not have the luxury (speed, memory- take your pick) but they can set aside some space in the memory. This space can be overwritten (overlayed if you will) as an when it is necessary.

    Simply put overlays are part of the game code, they are usually used for the less common functions. What games will use them I can not say (I have seen RPGs not touch them and simple puzzle games use them all the time and vice versa), I have yet to see anything other than a 0 kilobyte ARM7 one though.

    Note they are often LZ compressed.
  3. Noitora

    Noitora ::

    Aug 9, 2007
    All of Eyeshield 21 DS's script text is stored in overlays, overlays might also contain text.