Have you ever tried installing mods to join one online server, just to have to go back and switch them out for other mods for another server? What about switching to an entirely different version of the game, and then applying different versions of the same mods on top of that? The madness!
Don't worry, this (eventually) won't be an issue any longer!
Open sourced under the GPL v3 license, "Minecraft Offline" is an attempt at a custom Minecraft launcher written in the AutoIt scripting language to make modding environments easier to setup. Due to the scripting language, this custom launcher is limited to Windows, however a rewrite will take place to support all three major platforms in the near future.
Because of the work-in-progress status, please take note that the above-mentioned features are not yet implemented. This custom launcher is in a very early alpha state and is not ready to be used in any way for the average end user. This post is being made to allow people who have an interest in the idea to watch the idea expand and develop into what it's planned to be, and hopefully not be let down in the long run. Development will be high on weekends and rare throughout the week. No compiled binaries will be released until Minecraft can be successfully launched, so any testing will require setting up the AutoIt environment on your local Windows computer.
Current features as of the time of this writing:
Successfully login to your Mojang account (legacy Minecraft accounts will be implemented later on, but you should've migrated a long time ago :P)
Create a barebone directory structure to operate in
Download version manifest
Parse version manifest to get latest release version (commented out, but also snapshot version)
Download chosen version's index data
Download chosen version's JAR file
Properly support Mojang's Yggdrasil authentication service, including logging out
Implement proper logic for launching the chosen Minecraft version
Download all game assets and libraries required for the chosen Minecraft version
Support HTTP-based mod repositories hosted by server owners
Download required mods straight from the mod repository
Download additional resource packs and apply them pre-launch of game rather than wait for the in-game download prompt
Automatically join vanilla and modded servers after the game loads (as you have to close the game to install new mods anyhow)
There is no planned finish date for this project, however development should progress well during the next few months.
If you support the idea, please give the repository a star and even add it to your watch list! All feedback and support is highly appreciated, even if it's negative. The impact of this project may depend on feedback alone and whether such a launcher should even exist. If you wish to contribute to the project, fork the repository and then submit a pull request after you've finished making your changes. Not all contributions may be accepted due to possibility of feature addition/removal.
And now to hope I've posted this in the right forum...