Hyrule Builder

A mod building tool for The Legend of Zelda: Breath of the Wild.

Hyrule Builder is designed to help BOTW modders more easily manage and edit their project files. It can "unbuild"/"decompile" game files to a source-like format. All SARCs are extracted, all BYML, AAMP, or MSYT files are converted to YAML, and actor packs are specially unbuilt using canonical paths. The whole project can be easily rebuilt into usable mod, with a number of convenience features to smooth the process.

Setup

Download the latest release and extract the Hyrule Builder executable.

Project Management

Each mod you work on with Hyrule Builder is handled as its own project. Projects can be initialized from an existing mod, which will be unbuilt to the Hyrule Builder project format, or created fresh. Once a project is setup, it can be edited and built, with support for fast incremental rebuilds.

Hyrule Builder supports both Wii U and Switch mods, but each has a different format.

Wii U layout:

. (root mod folder)
├── content
│   └── (content folders, e.g. Actor, Pack, etc.)
└── aoc (for DLC files)
    └── (DLC folders, e.g. Map, Pack, etc.)

Switch layout (note: title IDs are case sensitive):

. (root mod folder)
├── 01007EF00011E000 (base game files)
│   └── romfs
│       └── (content folders, e.g. Actor, Pack, etc.)
└── 01007EF00011F001 (DLC files)
    └── romfs
        └── (content folders, e.g. Map, Pack, etc.)

Create a New Proejct

To create a new, blank mod project, run hyrule_builder init, which will prepare a new project in the current working directory. Pass the --be flag if creating a Wii U mod. The basic folder structure and an empty database of mod files will be created.

Initialize from Existing Mod Files

To turn existing mod files into a Hyrule Builder project, first make sure they are in the correct format as described above. Then run the init command with the -s/--source flag, e.g.:

hyrule_builder init -s BreathOfTheWild_VeryCleverMod

Further Usage Details

For details on initializing projects, see the help for the init command:

hyrule_builder init 0.9.0
Create a new source-like mod project

USAGE:
    hyrule-builder init [FLAGS] [OPTIONS] [directory]

FLAGS:
    -b, --be         Use big endian/Wii U mode
    -c, --config     Create default config.yml
    -h, --help       Prints help information
    -V, --version    Prints version information

OPTIONS:
    -s, --source <source>    Source mod folder to unbuild

ARGS:
    <directory>    Target folder to create project in [default: .]

Building

By default, when you build a project, the output files will be stored in the build folder of the project. For full information on building and its options, consult the usage info below:

hyrule_builder build 0.9.0
Build a mod from a source-like structure into binary game files 
Note: Flags can be set using a config.yml file. See readme for details

USAGE:
    hyrule-builder build [FLAGS] [OPTIONS] [--] [source]

FLAGS:
    -b, --be                 Use big endian/Wii U mode
    -h, --hard-warnings      Treat warnings as errors and abort
        --help               Prints help information
    -i, --ignore-warnings    Suppress warnings, show only errors
    -V, --version            Prints version information

OPTIONS:
    -o, --output <output>                   Output folder for built mod
    -t, --title-actors <title-actors>...    Comma separated list of custom actors to add to TitleBG.pack, e.g.
                                            `--title-actors=Weapon_Bow_001,Enemy_Golem_Senior`

ARGS:
    <source>    Source mod folder to build

Building a mod will automatically generate an updated RSTB file.

As the help says, instead of using command line arguments, you can also configure the build command by providing a config.yml file. It supports up to three sections, each of which is optional. The Meta section provides data that will be written into a rules.txt file in the output mod. The Flags section turns simple switchflags on by name in a list. The Options section is for flags that store arbitary values, like title-actors or output. An example config file is included below:

Meta: # specify data to go into a rules.txt file here
  name: A Mod
  description: My new mod
Flags: # list the switch flags you want turned on
  - be
  - ignore-warnings
Options: # provide values for customizable flags
  title-actors: Weapon_Bow_001,Enemy_Lizalfos_Senior
  output: test/TestMod_built

Adding Files to Projects

While it is possible to manually create new mod files or copy them in an unbuilt for from your game dump when adding new content, Hyrule Builder also includes asset management commands to simplify the process. To use this, first you will need to configure your game dump settings using the config command, e.g. hyrule_builder config import --from-bcml. (For more info on the config command, check the usage information with --help.)

Once your game dump settings are configured, you can use the add command to add content from your dump. Usage information:

hyrule_builder add 0.9.0
Add new content to the active mod project

USAGE:
    hyrule-builder add [OPTIONS] <SUBCOMMAND>

FLAGS:
    -h, --help       Prints help information
    -V, --version    Prints version information

OPTIONS:
    -p, --project <project>    Project folder to add to [default: .]

SUBCOMMANDS:
    actor        Add an actor to the current project, either modifying a vanilla actor or duplicating it as a new
                 one
    actorinfo    Adds unbuilt actor info to the current project
    event        Add an event to the current project, either modifying a vanilla event or duplicating it as a new
                 one
    help         Prints this message or the help of the given subcommand(s)
    map          Add a map unit to the current project
    pack         Add a root game pack to the mod (e.g. `Bootup.pack`, `AocMainField.pack`, etc.)

Notes on Project Layout

Most of a Hyrule Builder project layout will be familiar to anyone who has worked with BOTW mods, especially graphic packs, before. However, the following aspects are unique to Hyrule Builder:

• ActorInfo.product.sbyml becomes the Actor/ActorInfo folder with individual YAML files for each actor. The hash list is handled automatically. Simply adding a new YAML file to the folder will add it to the actor list and hash list.
• EventInfo.product.sbyml works roughly the same way, under Event/EventInfo.
• Most SARC files are unbuilt in place with their original filename, e.g. Pack/TitleBG.pack simply becomes a folder with the same name. However, actor packs are unbuilt fully into the Actor folder and rebuilt from their actor link files. For example, if you were to make a new copy of Actor/ActorLink/Enemy_Lizalfos_Senior.bxml.yml in your project and name it Enemy_Lizalfos_Geezer.bxml.yml, this change alone would cause the build process to create a new actor pack at Actor/Pack/Enemy_Lizalfos_Geezer.sbactorpack.
• Some SARC files which are parsed by standard Nintendo libraries instead of the BOTW resource system will not be unbuilt for safety reasons.

License

This software is licensed under the terms of the GNU General Public License, version 3 or later.