How does forge work?

[Luna_Genesis]

I've been pondering the nature of forge mod loader wondering how it's possible I always thought mods were kinda officially supported but after doing a little modding I kinda got this idea in my mind where they decompiled minecraft and hooked into one of the preloading classes but that seems like a LOT of work for every minecraft release...

Does forge depend on the minecraft release? I mean did they have to fix a decomp and make it run or is there something that allows them to indirectly target and execute methods and such?

<Other implicit questions I should be asking but don't even know how to phrase?>

[quaiby]

Here you can find a little bit about how Forge works: http://mcforge.readthedocs.io/en/latest/forgedev/

 

Of course Forge depends on the Minecraft release and they need to fix patches for newer Minecraft versions, but most of the code doesn't change from one version to the another in Minecraft. Also devs from Mojang coded MCP - Mod Coder Pack - tool, that help Forge devs to decompile and deobfuscate Minecraft.

 

Forge has 2 main parts: patches and everything else. Patches are small files that tell compiler where to change original code. Forge's patches for Minecraft are as tiny as possible. They just call code from other parts of Forge to minimize changes to make migration to newer releases easier. Forge contain not only event hooks, but a lots of its own stuff to make modding easier: Registries, abstract layers above Minecraft code to avoid conflicts, utility classes, event buses and so on.

Edited April 29, 2018 by quaiby

[JaredBGreat]

Well, no, they've never been officially supported, just condoned by the EULAs.  Just if you've wondered, a brief history of modding (possibly oversimplified with errors):

 

In the beginning there was MCP (Minecraft Coder Project), which, like Forge, was third-party.  It provided utilities that decompiled and deobfuscated Minecraft for modding.  It was all about "install mods" (aka, "jar mods") -- to install a mod you actually had to open minecraft.jar with a tool for zip files (jar's really are speciallized zip files).  If something went wrong the game could break (so you backed up the jar) and if two mods changed the same class they could not be used together -- the second one you installed would break the first by overwriting its changes.

 

Then came two innovations.  One was the mod loader, of which there were several (Rasgumi's, LiteLoader, etc.) -- you could install those mods and then they could load other mods.  Second there was Forge, which included APIs and ways to avoid modding base classes directly.  Then, Forge added its own built-in Forge Mod Loader (FML).  Installing mods in the jar was then obsolete, modding was much safer, and huge modpacks became possible and eventually common.  However, modding Minecraft has never been like modding most games -- you really are hacking the games binary either directly or indirectly.  With Forge, you can avoid hacking the core game.  Still, new release break everything, and force MCP and Forge to fix everything for the new versions; I'm sure all the work is why the Forge team doesn't want to support really old game versions.

 

I might want to look at the link given above for the details, as I never worried about it too much.  But I do know this -- the ability to load new code at run time is part of the Java language, supported through what are called classloaders.  Modding if possible because of the nature of the Java language rather than the intentional design or Notch or Mojang.  Thus, Forge only works for the "Java edition."

[jabelar]

And regarding the other part of the question -- yes it is a lot of work for the Forge community whenever there is a major Minecraft upgrade.

Edited April 30, 2018 by jabelar

[Draco18s]

4 hours ago, JaredBGreat said:

Second there was Forge, which included APIs and ways to avoid modding base classes directly.  Then, Forge added its own built-in Forge Mod Loader (FML).

Not quite. I believe Forge Mod Loader is actually a layer that allows Mod Loader mods to work with a Forge installation.

As a result, the two systems "merged" (originally just compatible, but Mod Loader is no longer, while Forge still exists)

[Cadiboo]

On 30/04/2018 at 4:01 AM, quaiby said:

Also devs from Mojang coded MCP - Mod Coder Pack - tool, that help Forge devs to decompile and deobfuscate Minecraft.

I think its important to note that MCP was NOT made by Mojang, and that amazing amounts of work have to be put into this tool every version to keep it up to date and readable! Every variable in Minecraft source code has obfuscated names and every variable in Decompiled code that has a logical name was named by someone who took the time to understand the variable and what it does enough to name it.

[Draco18s]

9 hours ago, Cadiboo said:

by someone who took the time to understand the variable and what it does enough to name it.

I renamed a parameter in a function once.

I'd have done it more, but I forgot the syntax MCPBot uses to override the protections on letting people rename anything (as you can't edit the javadoc without said override).

[Cadiboo]

13 hours ago, Draco18s said:

I renamed a parameter in a function once.

I'd have done it more, but I forgot the syntax MCPBot uses to override the protections on letting people rename anything (as you can't edit the javadoc without said override).

is there anywhere that has a tutorial on MCPBot syntax? I've actually had to go through quite a lot of source code and understand it and I would like to put my experience into the MCPBot

[Choonster]

57 minutes ago, Cadiboo said:

is there anywhere that has a tutorial on MCPBot syntax? I've actually had to go through quite a lot of source code and understand it and I would like to put my experience into the MCPBot

The documentation explains the commands here.