TelepathicGrunt

What are mixins?

Mixins are a way to inject code or change the minecraft source code directly and should be use with caution. If you can do a PR to Forge or use an event, try those first. If all else fails, then mixins may be a good option to look into. Here are some resources for mixins:

• Mixin Official Docs: https://github.com/SpongePowered/Mixin/wiki
• Mixin Javadocs: https://jenkins.liteloader.com/view/Other/job/Mixin/javadoc/index.html
• Mixin Cheatsheet: https://github.com/2xsaiko/mixin-cheatsheet
• MixinExtras (Adds some powerful compatiable mixin options!): https://github.com/LlamaLad7/MixinExtras

Now, I'll be honest, the official mixin doc is kind of terrible to learn from for most people. It's extremely dense and and really only helps people who already knows in-depth bytecode and stuff. But most modders aren't like that and just wants to do small stuff lol. But I'll give you the run-down here. There's a few kinds of mixins that you will encounter quite often.

killjoy1221

package mnm.mods.tabbychat.client.gui;

import com.mojang.blaze3d.platform.GlStateManager;
import net.minecraft.client.MainWindow;
import net.minecraft.client.gui.toasts.IToast;
import net.minecraft.client.gui.toasts.ToastGui;
import net.minecraft.util.text.ITextComponent;
import net.minecraft.util.text.TextFormatting;
import org.lwjgl.opengl.GL11;

williewillus

<?xml version="1.0" encoding="UTF-8"?>
<migrationMap>
  <name value="1.13.2 to 1.14" />
  <description value="1.13.2 to 1.14 MCP changes" />
  <entry oldName="net.minecraft.GameVersion" newName="net.minecraft.util.MinecraftVersion" type="class" />
  <entry oldName="net.minecraft.advancements.AdvancementList.Listener" newName="net.minecraft.advancements.AdvancementList.IListener" type="class" />
  <entry oldName="net.minecraft.advancements.RequirementsStrategy" newName="net.minecraft.advancements.IRequirementsStrategy" type="class" />
  <entry oldName="net.minecraft.advancements.criterion.AbstractCriterionInstance" newName="net.minecraft.advancements.criterion.CriterionInstance" type="class" />
  <entry oldName="net.minecraft.block.Block.EnumOffsetType" newName="net.minecraft.block.Block.OffsetType" type="class" />
  <entry oldName="net.minecraft.block.BlockAbstractBanner" newName="net.minecraft.block.AbstractBannerBlock" type="class" />

williewillus

This primer is licensed under CC0, do whatever you want.

BUT do note that this can be updated, so leave a link here so readers can see the updated information themselves.

1.13 and 1.14 are lumped together in this doc, you're on your own if you just want to go to 1.13 and not 1.14, for some reason.

1.15 stuff: https://gist.github.com/williewillus/30d7e3f775fe93c503bddf054ef3f93e

Things in Advance

• ResourceLocation now throw on non-snake-case names instead of silently lowercasing for you, so you probably should go and change all those string constants now. More precisely, domains must only contain alphanumeric lowercase, underscore (_), dash (-), or dot (.). Paths have the same restrictions, but can also contain forward slashes (/).

williewillus

// You can include this in your mod/a pack/whatever you want, as long as that work follows the Mojang EULA.
// The original source is viewable at https://gist.github.com/williewillus/a1a899ce5b0f0ba099078d46ae3dae6e

// This is a janky JSON generator, for porting from below 1.12 to 1.12.
// Simply replace calls to GameRegistry.addShapeless/ShapedRecipe with these methods, which will dump it to a json in RECIPE_DIR
// Also works with OD, replace GameRegistry.addRecipe(new ShapedOreRecipe/ShapelessOreRecipe with the same calls
// After you are done, call generateConstants()
// Note that in many cases, you can combine multiple old recipes into one, since you can now specify multiple possibilities for an ingredient without using the OD. See vanilla for examples.

	private static final Gson GSON = new GsonBuilder().setPrettyPrinting().create();