Current MCP-Minecraft version: 1.20.6

Prerequisites - Requirements

• Repository
• Eclipse IDE - https://www.eclipse.org/downloads/ (I use 2024.3)
• JDK 21 - https://www.oracle.com/tr/java/technologies/downloads/#java21

Tutorial

Here you can find everything about compiling minecraft LEGALLY!

Setting up the environment

• You can use Intellij IDEA too but this tutorial will cover about Eclipse.

Install the repository by clicking Code -> Download ZIP or you can git clone.

Install Eclipse IDE on your PC, then open that file you installed, you should see something like this:

Select "Eclipse IDE for Java Developers", set your settings and press "INSTALL".

Open Eclipse and select a workspace.

After selecting the workspace you should see something like this:

If you dont seeing it, just close the "Welcome" tab.

Setting up the MCP - Minecraft Source Code

First of all, Install JDK 21.

Go To Window -> Preferences -> Gradle

Change "Java home" to: C:\Program Files\Java\jdk-21

Go To Java -> Installed JREs

Press Add and Select Standart VM

Set "JRE home" to: C:\Program Files\Java\jdk-21

Should Look Like this:

Click Finish and then press Apply and Close

Press "Import Projects..." and Click "Gradle" and Add the MCP folder by pressing "Existing Gradle Project"

Set your project root directory by selecting the MCP Folder and press "Open".

Just click "Finish" button and wait until the process done. (This will take a while depending your internet connection speed.)

When its done, you should see "Gradle Tasks" Tab at the bottom. Just expand "mcp-reborn" file.

Okay, now we first need to expand "mcp" and Press "setup". Wait until execution done.

Then, Expand "mcp" file again and Press "copyAssets". Wait until execution done.

And Then, Expand "ide" file again and Press "eclipse". Wait until execution done.

Refresh the "Package Explorer" by Right Clicking a blank place in Package Explorer.

And the last thing is, Watch this video in order to Run the game:

2024-02-04.03-03-43.mp4

Compiling MCP Jar

For distributing your custom minecraft.

Watch the video in order to make your own custom minecraft version:

2024-02-04.03-20-34.mp4

DONE, JUST PUT THAT JAR FILE TO "mcp-test" FOLDER AND CHANGE THE JAR NAME SAME AS JSON FILE NAME AND PUT THAT FOLDER TO appdata -> roaming -> .minecraft -> versions

Troubleshooting

When i change some file in the client-extra.jar, the game crashes

This happens because the Minecraft checks the files first, then start the game. You can fix it by just watching the video:

2024-02-04.03-11-47.mp4

Follow the path that is in the right of client-extra.jar file, im on linux so thats why its different than Windows.

For windows, the path will be like: C:\Users\yourname\.gradle\caches\forge_gradle\minecraft_repo\versions\1.20.6-20240429.135109

Dont mind the screen flickering in the videos, i just fixed this by changing opengl settings and it works well now, sorry for the problem.

Modding

Head over to the wiki page!

NOTE: This wiki page is not ready yet.