mixin Mixin works in development environment but not in normal Minecraft

[Top-Set98]

Hi, I'm trying to get into Mixin.

My test code accesses the private attribute fps in the Minecraft class.
In the development environment (IntelliJ), it outputs the FPS, as I expected it would.
But when I try it in the normal Minecraft, it crashes, and I'm not sure why.

The Mixin Code:

@Mixin(Minecraft.class)
public interface MinecraftMixin {

    @Accessor("fps")
    int getFps();
}

How I call the mixin code:

@SubscribeEvent
public void onTick(ClientTickEvent event) {

    if (Minecraft.getInstance().player == null) {
        return;
    }

    if (Minecraft.getInstance().player.isCrouching()) {
        int test = ((MinecraftMixin)Minecraft.getInstance()).getFps();
        LOGGER.info(String.valueOf(test));
    }
}

Crashlog:

https://paste.ee/p/PtO7B

Edited May 26 by Top-Set98

[a_random_something]

Having the same problem. Could you let me know if you ever figure it out?

[Top-Set98]

On 5/28/2024 at 5:55 PM, a_random_something said:

Having the same problem. Could you let me know if you ever figure it out?

If I find something, of course.

 

I have tried a bit but I can't get mixin to run on 1.20.6 even with the latest version: 1.20.6 - 50.1.1.

[Top-Set98]

Still not working on Forge 1.21 - 51.0.6

[a_random_something]

I figured it out! Here's how I solved it:

I added:

"refmap": "<your_mod_id>.mixins.refmap.json" to my mixin json file and that solved it. You'll also need to add:

add sourceSets.main, '<your_mod_id>.mixins.refmap.json' to your build.gradle in the "mixin" block

 

my mixin file looks like this:

 

{
  "required": true,
  "minVersion": "0.8",
  "package": "<your_package>.<your_modid>.mixin",
  "compatibilityLevel": "JAVA_16",
  "refmap": "<your_mod_id>.mixins.refmap.json",
  "mixins": [
    "YourMixin1",
    "YourMixin2"
  ],
  "client": [
  ],
  "injectors": {
    "defaultRequire": 1
  }
}

This was in 1.19.2, but I don't think it should be too different

Edited June 17 by a_random_something

[Top-Set98]

My sample mod has the refmap in the mixin json file as well as "add sourceSets.main" in the "mixin" block. It is like in the documentation.

 

mixin json:

{
    "required": true,
    "minVersion": "0.8",
    "package": "com.example.examplemod.mixin",
    "compatibilityLevel": "JAVA_17",
    "refmap": "mixins.ExampleMod.refmap.json",
    "mixins": [
      "MinecraftMixin"
    ],
    "injectors": {
      "defaultRequire": 1
    }
  }

 

mixin block in build.gradle

mixin {
    // MixinGradle Settings
    add sourceSets.main, 'mixins.ExampleMod.refmap.json'
    config 'mixins.ExampleMod.json'
}

 

On 6/18/2024 at 12:41 AM, a_random_something said:

This was in 1.19.2, but I don't think it should be too different

I tried it on another Minecraft version (1.19.2 and 1.20.1) and it works.
As soon as I try Minecraft version 1.20.6 or higher it does not work anymore.

Edited Thursday at 05:26 PM by Top-Set98