Attempted to get mudballs working. Seems entity registration is buggy

src/main/java/biomesoplenty/api/entity/BOPEntities.java

@@ -0,0 +1,15 @@
+/*******************************************************************************
+ * Copyright 2014-2019, the Biomes O' Plenty Team
+ *
+ * This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Public License.
+ *
+ * To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.
+ ******************************************************************************/
+package biomesoplenty.api.entity;
+
+import net.minecraft.entity.EntityType;
+
+public class BOPEntities
+{
+    public static EntityType<?> mudball;
+}

src/main/java/biomesoplenty/common/entity/projectile/EntityMudball.java

@@ -0,0 +1,63 @@
+/*******************************************************************************
+ * Copyright 2014-2019, the Biomes O' Plenty Team
+ *
+ * This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Public License.
+ *
+ * To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.
+ ******************************************************************************/
+package biomesoplenty.common.entity.projectile;
+
+import biomesoplenty.api.entity.BOPEntities;
+import net.minecraft.entity.EntityLivingBase;
+import net.minecraft.entity.projectile.EntityThrowable;
+import net.minecraft.util.DamageSource;
+import net.minecraft.util.math.RayTraceResult;
+import net.minecraft.world.World;
+import net.minecraftforge.api.distmarker.Dist;
+import net.minecraftforge.api.distmarker.OnlyIn;
+
+public class EntityMudball extends EntityThrowable
+{
+    public EntityMudball(World world)
+    {
+        super(BOPEntities.mudball, world);
+    }
+
+    public EntityMudball(double x, double y, double z, World world)
+    {
+        super(BOPEntities.mudball, x, y, z, world);
+    }
+
+    public EntityMudball(World world, EntityLivingBase thrower)
+    {
+        super(BOPEntities.mudball, thrower, world);
+    }
+
+    @OnlyIn(Dist.CLIENT)
+    @Override
+    public void handleStatusUpdate(byte id)
+    {
+        if (id == 3)
+        {
+            for (int i = 0; i < 8; ++i)
+            {
+                //BiomesOPlenty.proxy.spawnParticle(BOPParticleTypes.MUD, this.world, this.posX, this.posY, this.posZ);
+            }
+        }
+    }
+
+    @Override
+    protected void onImpact(RayTraceResult hit)
+    {
+        if (hit.entity != null)
+        {
+            hit.entity.attackEntityFrom(DamageSource.causeThrownDamage(this, this.getThrower()), 0.0F);
+        }
+
+        if (!this.world.isRemote)
+        {
+            this.world.setEntityState(this, (byte)3);
+            this.remove();
+        }
+    }
+}

src/main/java/biomesoplenty/common/item/ItemMudball.java

@@ -0,0 +1,51 @@
+/*******************************************************************************
+ * Copyright 2014-2019, the Biomes O' Plenty Team
+ *
+ * This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Public License.
+ *
+ * To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.
+ ******************************************************************************/
+package biomesoplenty.common.item;
+
+import biomesoplenty.common.entity.projectile.EntityMudball;
+import biomesoplenty.common.util.inventory.ItemGroupBOP;
+import net.minecraft.entity.player.EntityPlayer;
+import net.minecraft.init.SoundEvents;
+import net.minecraft.item.Item;
+import net.minecraft.item.ItemStack;
+import net.minecraft.stats.StatList;
+import net.minecraft.util.ActionResult;
+import net.minecraft.util.EnumActionResult;
+import net.minecraft.util.EnumHand;
+import net.minecraft.util.SoundCategory;
+import net.minecraft.world.World;
+
+public class ItemMudball extends Item
+{
+    public ItemMudball()
+    {
+        super(new Item.Builder().group(ItemGroupBOP.instance).maxStackSize(16));
+    }
+
+    @Override
+    public ActionResult<ItemStack> onItemRightClick(World world, EntityPlayer player, EnumHand hand)
+    {
+        ItemStack stack = player.getHeldItem(hand);
+        if (!player.abilities.isCreativeMode)
+        {
+            stack.setCount(stack.getCount() - 1);
+        }
+
+        world.playSound(player, player.getPosition(), SoundEvents.ENTITY_ARROW_SHOOT, SoundCategory.NEUTRAL, 0.5F, 0.4F / (random.nextFloat() * 0.4F + 0.8F));
+
+        if (!world.isRemote)
+        {
+            EntityMudball mudball = new EntityMudball(world, player);
+            mudball.shoot(player, player.rotationPitch, player.rotationYaw, 0.0F, 1.5F, 1.0F);
+            world.spawnEntity(mudball);
+        }
+
+        player.addStat(StatList.ITEM_USED.get(this));
+        return new ActionResult<ItemStack>(EnumActionResult.SUCCESS, stack);
+    }
+}

src/main/java/biomesoplenty/core/BiomesOPlenty.java

@@ -9,9 +9,11 @@
 package biomesoplenty.core;
 
 import biomesoplenty.init.ModBlocks;
+import biomesoplenty.init.ModEntities;
 import biomesoplenty.init.ModItems;
 import biomesoplenty.init.ModSounds;
 import net.minecraft.init.Bootstrap;
+import net.minecraftforge.fml.DistExecutor;
 import net.minecraftforge.fml.common.Mod;
 import net.minecraftforge.fml.common.event.FMLInitializationEvent;
 import net.minecraftforge.fml.common.event.FMLPreInitializationEvent;
@@ -23,6 +25,7 @@ public class BiomesOPlenty
     public static final String MOD_ID = "biomesoplenty";
 
     public static BiomesOPlenty instance;
+    public static CommonProxy proxy = DistExecutor.runForDist(() -> ClientProxy::new, () -> CommonProxy::new);
 
     public BiomesOPlenty()
     {
@@ -32,12 +35,14 @@ public class BiomesOPlenty
         FMLModLoadingContext.get().getModEventBus().addListener(this::init);
 
         ModSounds.init();
+        ModEntities.init();
         ModBlocks.init();
         ModItems.init();
     }
     
     private void preInit(final FMLPreInitializationEvent event)
     {
+        proxy.preInit();
     }
 
     private void init(final FMLInitializationEvent event)

src/main/java/biomesoplenty/core/ClientProxy.java

@@ -0,0 +1,29 @@
+/*******************************************************************************
+ * Copyright 2014-2019, the Biomes O' Plenty Team
+ *
+ * This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Public License.
+ *
+ * To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.
+ ******************************************************************************/
+package biomesoplenty.core;
+
+import biomesoplenty.api.item.BOPItems;
+import biomesoplenty.common.entity.projectile.EntityMudball;
+import net.minecraft.client.Minecraft;
+import net.minecraft.client.renderer.entity.RenderSprite;
+import net.minecraft.entity.Entity;
+import net.minecraftforge.fml.client.registry.RenderingRegistry;
+
+public class ClientProxy extends CommonProxy
+{
+    public ClientProxy()
+    {
+
+    }
+
+    @Override
+    public void preInit()
+    {
+        RenderingRegistry.registerEntityRenderingHandler(EntityMudball.class, manager -> new RenderSprite<Entity>(manager, BOPItems.mudball, Minecraft.getInstance().getItemRenderer()));
+    }
+}

src/main/java/biomesoplenty/core/CommonProxy.java

@@ -0,0 +1,18 @@
+/*******************************************************************************
+ * Copyright 2014-2019, the Biomes O' Plenty Team
+ *
+ * This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Public License.
+ *
+ * To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.
+ ******************************************************************************/
+package biomesoplenty.core;
+
+public class CommonProxy
+{
+    public CommonProxy()
+    {
+
+    }
+
+    public void preInit() {}
+}

src/main/java/biomesoplenty/init/ModEntities.java

@@ -0,0 +1,94 @@
+/*******************************************************************************
+ * Copyright 2014-2019, the Biomes O' Plenty Team
+ *
+ * This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Public License.
+ *
+ * To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.
+ ******************************************************************************/
+package biomesoplenty.init;
+
+import biomesoplenty.common.entity.projectile.EntityMudball;
+import com.mojang.datafixers.DataFixUtils;
+import com.mojang.datafixers.types.Type;
+import net.minecraft.entity.Entity;
+import net.minecraft.entity.EntityType;
+import net.minecraft.entity.monster.EntitySpider;
+import net.minecraft.item.Item;
+import net.minecraft.util.SharedConstants;
+import net.minecraft.util.datafix.DataFixesManager;
+import net.minecraft.util.datafix.TypeReferences;
+import net.minecraft.world.World;
+import net.minecraftforge.registries.ForgeRegistries;
+
+import java.util.function.Function;
+
+import static biomesoplenty.api.entity.BOPEntities.*;
+
+public class ModEntities
+{
+    public static void init()
+    {
+        mudball = registerEntity(FixedEntityTypeBuilder.create(EntityMudball.class, EntityMudball::new), "mudball");
+    }
+
+    public static <T extends Entity> EntityType<T> registerEntity(FixedEntityTypeBuilder<T> typeBuilder, String name)
+    {
+        EntityType<T> type = typeBuilder.build("biomesoplenty:" + name);
+        type.setRegistryName(name);
+        ForgeRegistries.ENTITIES.register(type);
+        return type;
+    }
+
+    // TODO: Remove this once Forge has fixed the bugs with calling build in
+    // EntityType.Builder, causing an exception when registering entities
+    public static class FixedEntityTypeBuilder<T extends Entity>
+    {
+        private final Class<? extends T> entityClass;
+        private final Function<? super World, ? extends T> factory;
+        private boolean serializable = true;
+        private boolean summonable = true;
+
+        private FixedEntityTypeBuilder(Class<? extends T> entityClassIn, Function<? super World, ? extends T> factoryIn)
+        {
+            this.entityClass = entityClassIn;
+            this.factory = factoryIn;
+        }
+
+        public static <T extends Entity> FixedEntityTypeBuilder<T> create(Class<? extends T> entityClassIn, Function<? super World, ? extends T> factoryIn)
+        {
+            return new FixedEntityTypeBuilder<T>(entityClassIn, factoryIn);
+        }
+
+        public static <T extends Entity> FixedEntityTypeBuilder<T> createNothing(Class<? extends T> entityClassIn)
+        {
+            return new FixedEntityTypeBuilder<T>(entityClassIn, (p_200708_0_) -> {
+                return null;
+            });
+        }
+
+        public FixedEntityTypeBuilder<T> disableSummoning()
+        {
+            this.summonable = false;
+            return this;
+        }
+
+        public FixedEntityTypeBuilder<T> disableSerialization()
+        {
+            this.serializable = false;
+            return this;
+        }
+
+        public EntityType<T> build(String id) {
+            Type<?> type = null;
+            if (this.serializable) {
+                try {
+                    type = DataFixesManager.getDataFixer().getSchema(DataFixUtils.makeKey(1519)).getChoiceType(TypeReferences.ENTITY_TYPE, id);
+                } catch (IllegalArgumentException e) {
+                    // Ignore, we don't care
+                }
+            }
+
+            return new EntityType<T>(this.entityClass, this.factory, this.serializable, this.summonable, type);
+        }
+    }
+}

src/main/java/biomesoplenty/init/ModItems.java

@@ -11,6 +11,7 @@ import static biomesoplenty.api.item.BOPItems.*;
 
 import biomesoplenty.api.sound.BOPSounds;
 import biomesoplenty.common.item.ItemBOPRecord;
+import biomesoplenty.common.item.ItemMudball;
 import biomesoplenty.common.util.inventory.ItemGroupBOP;
 import net.minecraft.item.Item;
 import net.minecraftforge.registries.ForgeRegistries;
@@ -19,8 +20,7 @@ public class ModItems
 {
 	public static void init()
 	{
-        // TODO: This should be ItemMudball
-        mudball = registerItem(new Item(new Item.Builder().group(ItemGroupBOP.instance)), "mudball");
+        mudball = registerItem(new ItemMudball(), "mudball");
         mud_brick = registerItem(new Item(new Item.Builder().group(ItemGroupBOP.instance)), "mud_brick");
         pile_of_ashes = registerItem(new Item(new Item.Builder().group(ItemGroupBOP.instance)), "pile_of_ashes");
         chunk_of_flesh = registerItem(new Item(new Item.Builder().group(ItemGroupBOP.instance)), "chunk_of_flesh");