MCInstance Loader - Modpack Installer Directly in Game
This compact mod enables the installation of .mcinstance format modpacks directly within Minecraft. This format represents a simplified method of distributing mod collections that supports downloading files from the internet, including additional resources, and many other features.
After successful installation, the game will prompt for a restart, and the .mcinstance file will be automatically disabled for proper client resumption.
Format and Mod Features
MCInstance Loader and its supported format offer a rich set of capabilities:
You can place any files in the overrides folder - they will be copied to the Minecraft root directory (typically .minecraft). A special carryover folder is also provided where players can add their own files that will merge with the modpack content.
The system supports downloading files from any URLs and saving them anywhere in the Minecraft folder. Integration with Modrinth and CurseForge APIs is implemented with multiple fallback modes in case of failures.
For verifying the integrity of downloaded files, hash sums are used (SHA-512, SHA-256, SHA-1, MD5, or CRC32). A caching system for hashed files is implemented to avoid re-downloading during updates.
The mod includes StopModReposts checks to prevent the use of repost sites (this feature can be disabled if needed). Separate files for client and server are also supported, which is useful for GUI mods.
Additional Capabilities
A flexible optional files system with selection menus, grouping support, multiple menus, and multi-choice interfaces with configurable numbers of toggleable items (currently client-side only, server implementation is planned).
A comprehensive logging system allows easy tracking of issues related to this mod. There's an option to enable verbose output in Forge logs.
An update checker is integrated to keep the mod current. A new progress bar has been added to the loading screen showing how many mods remain to be downloaded.
A customizable info interface replaces the main menu to notify users of errors or successful installation. Supports an auto-quit timer, custom success messages, and compatibility with mods that change the menu (a list of classes can be specified).
After successful installation, the pack.mcinstance file is automatically disabled with the option to delete it or disable this feature. This is necessary for normal gameplay after modpack installation.
What is the .mcinstance Format?
The MCInstance format (.mcinstance) is a repurposed ZIP archive with a specific internal structure containing .packconfig files similar to the INI format. The goal of this mod is to enable the installation of such files directly in the game, creating a cross-platform modpack format. Format support can also be added to third-party launchers for installing packs by double-clicking the file.
Future Plans
Currently, porting the mod to other versions is not underway but is planned for the future. The goal is to make the mcinstance format available to as many players as possible. Development is currently starting with version 1.7.10, porting to other versions will be done when the mod is ready.
Since the mod is distributed under the MIT license, you can help with porting by creating a pull request on GitHub for any version (be it 1.3.2, 1.18, Forge, Fabric, etc.).
Licensing and Acknowledgments
Although the mod is distributed under the MIT license, this does not apply to files in the net.lingala.zip4j package, as this is the source code of the zip4j library included for convenience. The zip4j library is licensed under Apache License 2.0, and the version included here is release 2.9.1.
Acknowledgments:
- Srikanth-lingala for creating the zip4j library used by this mod
- AstroTibs for OptionsEnforcer which inspired the development
- Janrupf and HansWasser for ModDirector which also influenced the creation of this mod
