[1.16.1] The Book of Minecraft Modding - complete guide for beginners

[tcode2k16 5]

I got into minecraft modding recently and was surprised by how hard it is to find useful up-to-date information. Because of that, I decided to document my learning journey and write a book about Minecraft modding for beginners. It applies to Minecraft 1.16.1 and the latest version of forge.

 

Keep in mind it is still a work in progress. More chapters will be added in the coming days. Suggestions and questions also are welcomed.

 

Link: https://thebookofmodding.ml/

[patryk0328 0]

Would you add particles, moving mobs like wind and flinging blocks pls because i want to make a working tornado mod. thx.

[ChampionAsh5357 176]

Please use object holder to "hold" the block and item instances when registering or use deferred register if you're going to statically initialize anything. What you have written for custom blocks is just wrong.

[Maxi07 2]

6 hours ago, ChampionAsh5357 said:

Please use object holder to "hold" the block and item instances when registering or use deferred register if you're going to statically initialize anything. What you have written for custom blocks is just wrong.

I register my items and blocks similar:

 

RegisterBlocks.java

package maxi.ores_cores.init;

import maxi.ores_cores.OresCores;
import maxi.ores_cores.blocks.*;
import maxi.ores_cores.items.BasicBlockItem;
import net.minecraft.block.Block;
import net.minecraft.item.Item;
import net.minecraft.item.ItemGroup;
import net.minecraftforge.event.RegistryEvent.Register;
import net.minecraftforge.eventbus.api.SubscribeEvent;
import net.minecraftforge.fml.common.Mod.EventBusSubscriber;
import net.minecraftforge.fml.common.Mod.EventBusSubscriber.Bus;
import net.minecraftforge.registries.IForgeRegistry;

@EventBusSubscriber(modid = OresCores.MODID, bus = Bus.MOD)
public class RegisterBlocks {

	@SubscribeEvent
	public static void registerBlock(Register<Block> event) {
		final IForgeRegistry<Block> registry = event.getRegistry();
		registry.register(MetalBlock.EMOULRITE_BLOCK.setRegistryName(OresCores.MODID, "emoulrite_block"));
		registry.register(Ore.EMOULRITE_ORE.setRegistryName(OresCores.MODID, "emoulrite_ore"));
		registry.register(MetalBlock.TELERITE_BLOCK.setRegistryName(OresCores.MODID, "telerite_block"));
		registry.register(Ore.TELERITE_ORE.setRegistryName(OresCores.MODID, "telerite_ore"));
	}
	
	@SubscribeEvent
	public static void registerItem(Register<Item> event) {
		final IForgeRegistry<Item> registry = event.getRegistry();
		registry.register(new BasicBlockItem(MetalBlock.EMOULRITE_BLOCK, ItemGroup.BUILDING_BLOCKS));
		registry.register(new BasicBlockItem(Ore.EMOULRITE_ORE, ItemGroup.BUILDING_BLOCKS));
		registry.register(new BasicBlockItem(MetalBlock.TELERITE_BLOCK, ItemGroup.BUILDING_BLOCKS));
		registry.register(new BasicBlockItem(Ore.TELERITE_ORE, ItemGroup.BUILDING_BLOCKS));
	}
}

 

MetalBlock.java (Ore.java is similar)

package maxi.ores_cores.blocks;

import net.minecraft.block.SoundType;
import net.minecraft.block.Block;
import net.minecraft.block.Block.Properties;
import net.minecraft.block.material.Material;
import net.minecraft.block.material.MaterialColor;
import net.minecraftforge.common.ToolType;

public class MetalBlock {
	
	public static final Block EMOULRITE_BLOCK = new Block(Properties
								.create(Material.IRON, MaterialColor.GOLD).sound(SoundType.METAL)
								.hardnessAndResistance(5, 6)
								.harvestTool(ToolType.PICKAXE).harvestLevel(2));
	
	public static final Block TELERITE_BLOCK = new Block(Properties
								.create(Material.IRON, MaterialColor.PURPLE).sound(SoundType.METAL)
								.hardnessAndResistance(5, 6)
								.harvestTool(ToolType.PICKAXE).harvestLevel(2));
	
}

 

BasicBlockItem.java

package maxi.ores_cores.items;

import net.minecraft.block.Block;
import net.minecraft.item.BlockItem;
import net.minecraft.item.ItemGroup;

public class BasicBlockItem extends BlockItem {

	public BasicBlockItem(Block block, ItemGroup group) {
		super(block, new Properties().group(group));
		setRegistryName(block.getRegistryName());
	}

}

 

Whats bad about this? I am new to modding and I appreciate every suggestion for improvement that I get

[diesieben07 7795]

Registration must occur during a very specific time (when the registry event is fired). By using a static initializer you are completely bypassing this and doing it when your class is initialized, which is not easy to know when it is.

[Maxi07 2]

3 minutes ago, diesieben07 said:

Registration must occur during a very specific time (when the registry event is fired). By using a static initializer you are completely bypassing this and doing it when your class is initialized, which is not easy to know when it is.

So I should make the methods that register the blocks and items non static?

[diesieben07 7795]

It's not about the methods. It's about you doing new Block(...) etc in a static initializer (static Block foo = <this here is the static intializer>).

[Maxi07 2]

2 hours ago, Maxi07 said:

public static final Block EMOULRITE_BLOCK = new Block(Properties .create(Material.IRON, MaterialColor.GOLD).sound(SoundType.METAL) .hardnessAndResistance(5, 6) .harvestTool(ToolType.PICKAXE).harvestLevel(2));

Oh okay, you mean this, right?

 

EDIT: Thanks for helping me improving my code @diesieben07

Edited July 4, 2020 by Maxi07

[diesieben07 7795]

Yes.

[tcode2k16 5]

On 7/4/2020 at 10:11 AM, ChampionAsh5357 said:

Please use object holder to "hold" the block and item instances when registering or use deferred register if you're going to statically initialize anything. What you have written for custom blocks is just wrong.

Thanks for pointing this out!

 

I updated the tutorial to use deferred registers.

 

Please let me know if you spot any further errors. I am happy to correct them as well

[zenglintao 1]

On 7/4/2020 at 1:09 AM, tcode2k16 said:

I got into minecraft modding recently and was surprised by how hard it is to find useful up-to-date information. Because of that, I decided to document my learning journey and write a book about Minecraft modding for beginners. It applies to Minecraft 1.16.1 and the latest version of forge.

 

Keep in mind it is still a work in progress. More chapters will be added in the coming days. Suggestions and questions also are welcomed.

 

Link: https://thebookofmodding.ml/

I want to know how to create and register an Events

[Novârch 31]

41 minutes ago, zenglintao said:

I want to know how to create and register an Events

Extend Event, then call MinecraftForge#EVENT_BUS#register to register it, remember you have to fire your event manually using MinecraftForge#EVENT_BUS#post.

Edited July 6, 2020 by Novârch

[Ugdhar 233]

Hopefully you make it further than most tutorial makers, who give up after all they cover the same stuff everyone else does!

 

Best of luck to you!

[Dernert 0]

Awesome. Please continue!

[Maxi07 2]

On 7/4/2020 at 4:11 AM, ChampionAsh5357 said:

Please use object holder to "hold" the block and item instances when registering or use deferred register if you're going to statically initialize anything.

Okay, now I am finally continue with modding. I am changing my whole registration system and how I add blocks and items. I dont want the static intializer problem, but I dont want to use DefferedRegisries either (please dont ask why). So I looked at the minecraft classes net.minecraft.block.Blocks and net.minecraft.item.Items where the minecraft blocks and items are registered. I want to do this similar. I should use ObjectHolders. I searched how they work but I couldn't find something that could help me. And now I am asking here. And please say if you have an idea how i could make my registration system without DefferedRegisries and problems.

Thanks!

Edited July 15, 2020 by Maxi07

[Novârch 31]

5 minutes ago, Maxi07 said:

I dont want the static intializer problem, but I dont want to use DefferedRegisries either

RegistryEvent, don't use vanilla registration if there is a Forge version available.

[diesieben07 7795]

6 minutes ago, Maxi07 said:

I want to do this similar.

You can't, vanilla is different.

 

If you do not want to use DeferredRegister (yes, I will ask why), you need to subscribe to RegistryEvent.Register for the appropriate type (e.g. RegistryEvent.Register<Block>) and register your things there.

Then to get hold of your instances either use @ObjectHolder (put it on a class, then the annotation value must be your mod ID and field names become the registry names for what to inject, fields do not need annotations; otherwise put it on individual fields, then the annotation value must be the full registry name including mod ID).

Otherwise you can also use RegistryObject:

public static final RegistryObject<Block> MY_COOL_BLOCK = RegistryObject.of(new ResourceLocation(...), ForgeRegistries.BLOCKS)

 

[Maxi07 2]

So will this already work?

package maxi.ores_cores.init;

import maxi.ores_cores.OresCores;
import maxi.ores_cores.items.BasicBlockItem;
import net.minecraft.block.Block;
import net.minecraft.block.SoundType;
import net.minecraft.block.Block.Properties;
import net.minecraft.block.material.Material;
import net.minecraft.block.material.MaterialColor;
import net.minecraft.item.Item;
import net.minecraft.item.ItemGroup;
import net.minecraftforge.common.ToolType;
import net.minecraftforge.event.RegistryEvent.Register;
import net.minecraftforge.eventbus.api.SubscribeEvent;
import net.minecraftforge.fml.common.Mod.EventBusSubscriber;
import net.minecraftforge.fml.common.Mod.EventBusSubscriber.Bus;
import net.minecraftforge.registries.IForgeRegistry;
import net.minecraftforge.registries.ObjectHolder;

@EventBusSubscriber(modid = OresCores.MODID, bus = Bus.MOD)
@ObjectHolder(value = OresCores.MODID)
public class RegisterBlocks {

	public static final Block EXAMPLE_BLOCK = new Block(Properties.create(Material.ROCK, MaterialColor.STONE).sound(SoundType.STONE).hardnessAndResistance(3, 3).harvestTool(ToolType.PICKAXE).harvestLevel(2));
	
	@SubscribeEvent
	public static void registerBlock(Register<Block> event) {
		final IForgeRegistry<Block> registry = event.getRegistry();
		registry.register(EXAMPLE_BLOCK.setRegistryName(OresCores.MODID, "emoulrite_block"));
	}
	
	@SubscribeEvent
	public static void registerItem(Register<Item> event) {
		final IForgeRegistry<Item> registry = event.getRegistry();
		registry.register(new BasicBlockItem(EXAMPLE_BLOCK, ItemGroup.BUILDING_BLOCKS));
	}
}

 

[diesieben07 7795]

No.

You cannot create instances of registry entries (e.g. Block) in static initializers.

[Maxi07 2]

Okay, then what I have to change? I want to have one instance of my block. Or is this stupid?

Sorry for being a bit annoying

[diesieben07 7795]

You create the instance in the registry event and then use @ObjectHolder or RegistryObject to obtain it outside.

In the future the registry events might fire again and then you need to re-register your things and Forge will automatically update any fields using @ObjectHolder or any RegistryObject. That will hopefully, eventually, enable the runtime loading and/or disabling/enabling of mods.

[Maxi07 2]

Of course, that makes a lot of sense! Excuse me for this silly question, but how I obtain my instance outside the registration?

[diesieben07 7795]

29 minutes ago, diesieben07 said:

Then to get hold of your instances either use @ObjectHolder (put it on a class, then the annotation value must be your mod ID and field names become the registry names for what to inject, fields do not need annotations; otherwise put it on individual fields, then the annotation value must be the full registry name including mod ID).

Otherwise you can also use RegistryObject:

public static final RegistryObject<Block> MY_COOL_BLOCK = RegistryObject.of(new ResourceLocation(...), ForgeRegistries.BLOCKS)

 

[Maxi07 2]

Now it finally works! Every tutorial I've seen used static initializers. What are the problems, why I should avoid them (I know you said something about timing above)? And by the way, is my code now finally not bad?

@EventBusSubscriber(modid = OresCores.MODID, bus = Bus.MOD)
public class RegisterBlocks {

	@SubscribeEvent
	public static void registerBlock(Register<Block> event) {
		
		final Block EXAMPLE_BLOCK = new Block(Properties.create(Material.ROCK, MaterialColor.STONE).sound(SoundType.STONE).hardnessAndResistance(3, 3).harvestTool(ToolType.PICKAXE).harvestLevel(2));
		
		final IForgeRegistry<Block> registry = event.getRegistry();
		registry.register(EXAMPLE_BLOCK.setRegistryName(OresCores.MODID, "example_block"));
	}
	
	@SubscribeEvent
	public static void registerItem(Register<Item> event) {
		final IForgeRegistry<Item> registry = event.getRegistry();
		registry.register(new BasicBlockItem(Blocks.EXAMPLE_BLOCK, ItemGroup.BUILDING_BLOCKS));
	}
}

Blocks.java:

@ObjectHolder(value = OresCores.MODID)
public class Blocks {

	public static final Block EXAMPLE_BLOCK = null;
	
}

 

[diesieben07 7795]

48 minutes ago, Maxi07 said:

Every tutorial I've seen used static initializers.

Those tutorials are bad then. Unfortunately most modding tutorials are written by amateurs, who don't even come here to ask for feedback before posting it as just "the way to do it" on Youtube, etc.

 

48 minutes ago, Maxi07 said:

What are the problems, why I should avoid them (I know you said something about timing above)?

Registration must happen exactly when Forge tells you. Forge does so by firing the registry event. If you use a static initializer you completely bypass this system. This prevents Forge from doing improvements in the future, such as reloading mods at runtime or even disabling/enabling them.

 

48 minutes ago, Maxi07 said:

And by the way, is my code now finally not bad?

Yes, it's fine now.

However if you do write a tutorial I would recommend you use DeferredRegister or at least RegistryObject as they are the current recommended approach. "Magic injection into fields" using @ObjectHolder is ugly. Why do you not want to use them?