I have an idea for a romhack, but I have a few questions

Discussion in '3DS - ROM Hacking, Translations and Utilities' started by StackMasher, May 28, 2017.

  1. StackMasher
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    StackMasher GBAtemp Regular

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    I thought a modding hook for "Lego City Undercover: The Chase Begins" would be cool since it's the most GTA like game we have on the 3DS and I want to make it but I have 2 questions:
    • How hard do you think such a project would be?
    • What's some useful documentation I could use? (I've never made romhacks before, I've done some amd64 assembly and modifying hex but not much)
     
  2. Ericjwg

    Ericjwg Good

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    1. unpack the game file. (https://github.com/Asia81/HackingToolkit3DS)
    2. crack those extracted files. (if any specific game research forum exist should helps, like ppporg for pokemon)
    3. edit it.
    4. repack.
    5. done.
     
    Last edited by Ericjwg, May 28, 2017
  3. StackMasher
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    StackMasher GBAtemp Regular

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    once I unpack my game cia, what files are executable, and where is the documentation for them?
     
    Last edited by StackMasher, May 28, 2017
  4. Ericjwg

    Ericjwg Good

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    there is no excutable file in 3ds game's archive...
    most companies are using different compression method for their archives.
    not all types of files are documented. (based on player base...)


    if the game doesnt have a large amount player base (which means will have less ppl doing research), you have to do the analyze/crack part by yourself.
     
    Last edited by Ericjwg, May 28, 2017
  5. StackMasher
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    StackMasher GBAtemp Regular

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    What do you mean there's no executable files? execfs/code.bin looks like what I'm looking for, does that contain the game code?
     
  6. Ericjwg

    Ericjwg Good

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    yes. but the file is not excutable in any sense.....

    — Posts automatically merged - Please don't double post! —

    based on your post, I'm guessing you want to have things like modeling edit?
    if you do. code.bin is not what you want
     
  7. StackMasher
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    I want to add some code that dynamically loads executables off the SD card, and calls them at certain points (e.g. when a button is pressed or every frame)
     
  8. Ericjwg

    Ericjwg Good

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    Oh… code.bin is what you need.
     
  9. StackMasher
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    One last question, where are the code.bin sections declared? According to this post I have to look in the exefs header but 3dbrew doesn't mention anything
     
    Last edited by StackMasher, May 29, 2017