[SOLVED]-[1.16.1] How to create an custom slime entity

[samjviana]

I'm new at this minecraft mod thing, and i was trying to make custom entities. I got to make an pig and a zombie, but failed on making a slime.
I'm using the "GlobalEntityTypeAttributes#put" to define the Attributes of the entity, along with SlimeEntity#func_233666_p_ and SlimeEntity#func_233639_cI_ to get AttributeModifierMap.
But when i use the SlimeEntity#func_233666_p_ i get:

java.lang.IllegalArgumentException: Can't find attribute minecraft:generic.follow_range
	at net.minecraft.entity.ai.attributes.AttributeModifierMap.func_233810_d_(AttributeModifierMap.java:21) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.entity.ai.attributes.AttributeModifierMap.func_233804_a_(AttributeModifierMap.java:28) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.entity.ai.attributes.AttributeModifierManager.func_233795_c_(AttributeModifierManager.java:67) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.entity.LivingEntity.func_233637_b_(LivingEntity.java:1848) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.pathfinding.PathNavigator.<init>(PathNavigator.java:47) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.pathfinding.GroundPathNavigator.<init>(GroundPathNavigator.java:16) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.entity.MobEntity.createNavigator(MobEntity.java:135) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.entity.MobEntity.<init>(MobEntity.java:114) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.entity.monster.SlimeEntity.<init>(SlimeEntity.java:54) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.ddns.samjviana.morethings.entity.BlueSlimeEntity.<init>(BlueSlimeEntity.java:9) ~[main/:?]
	at net.minecraft.entity.EntityType.create(EntityType.java:442) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.entity.EntityType.lambda$loadEntityUnchecked$1(EntityType.java:453) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at java.util.Optional.map(Optional.java:215) ~[?:1.8.0_221]
	at net.minecraft.entity.EntityType.loadEntityUnchecked(EntityType.java:452) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.entity.EntityType.loadEntity(EntityType.java:510) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.entity.EntityType.func_220335_a(EntityType.java:492) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.command.impl.SummonCommand.summonEntity(SummonCommand.java:49) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.command.impl.SummonCommand.lambda$register$1(SummonCommand.java:33) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at com.mojang.brigadier.CommandDispatcher.execute(CommandDispatcher.java:262) ~[brigadier-1.0.17.jar:?]
	at com.mojang.brigadier.CommandDispatcher.execute(CommandDispatcher.java:176) ~[brigadier-1.0.17.jar:?]
	at net.minecraft.command.Commands.handleCommand(Commands.java:218) ~[?:?]
	at net.minecraft.network.play.ServerPlayNetHandler.handleSlashCommand(ServerPlayNetHandler.java:1085) ~[?:?]
	at net.minecraft.network.play.ServerPlayNetHandler.processChatMessage(ServerPlayNetHandler.java:1065) ~[?:?]
	at net.minecraft.network.play.client.CChatMessagePacket.processPacket(CChatMessagePacket.java:40) ~[?:?]
	at net.minecraft.network.play.client.CChatMessagePacket.processPacket(CChatMessagePacket.java:8) ~[?:?]
	at net.minecraft.network.PacketThreadUtil.lambda$checkThreadAndEnqueue$0(PacketThreadUtil.java:19) ~[?:?]
	at net.minecraft.util.concurrent.TickDelayedTask.run(TickDelayedTask.java:20) ~[?:?]
	at net.minecraft.util.concurrent.ThreadTaskExecutor.run(ThreadTaskExecutor.java:139) ~[?:?]
	at net.minecraft.util.concurrent.RecursiveEventLoop.run(RecursiveEventLoop.java:22) ~[?:?]
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:763) ~[?:?]
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:157) ~[?:?]
	at net.minecraft.util.concurrent.ThreadTaskExecutor.driveOne(ThreadTaskExecutor.java:109) ~[?:?]
	at net.minecraft.server.MinecraftServer.driveOneInternal(MinecraftServer.java:746) ~[?:?]
	at net.minecraft.server.MinecraftServer.driveOne(MinecraftServer.java:740) ~[?:?]
	at net.minecraft.util.concurrent.ThreadTaskExecutor.driveUntil(ThreadTaskExecutor.java:122) ~[?:?]
	at net.minecraft.server.MinecraftServer.runScheduledTasks(MinecraftServer.java:726) ~[?:?]
	at net.minecraft.server.MinecraftServer.func_240802_v_(MinecraftServer.java:669) ~[?:?]
	at net.minecraft.server.MinecraftServer.lambda$func_240784_a_$0(MinecraftServer.java:231) ~[?:?]
	at java.lang.Thread.run(Thread.java:748) [?:1.8.0_221]

 

And with SlimeEntity#func_233639_cI_ i get:
 

net.minecraft.crash.ReportedException: Loading entity NBT
	at net.minecraft.entity.Entity.read(Entity.java:1660) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.entity.EntityType.lambda$loadEntityUnchecked$2(EntityType.java:455) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.util.Util.acceptOrElse(Util.java:319) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.entity.EntityType.loadEntityUnchecked(EntityType.java:452) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.entity.EntityType.loadEntity(EntityType.java:510) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.entity.EntityType.func_220335_a(EntityType.java:492) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.command.impl.SummonCommand.summonEntity(SummonCommand.java:49) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.command.impl.SummonCommand.lambda$register$1(SummonCommand.java:33) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at com.mojang.brigadier.CommandDispatcher.execute(CommandDispatcher.java:262) ~[brigadier-1.0.17.jar:?]
	at com.mojang.brigadier.CommandDispatcher.execute(CommandDispatcher.java:176) ~[brigadier-1.0.17.jar:?]
	at net.minecraft.command.Commands.handleCommand(Commands.java:218) ~[?:?]
	at net.minecraft.network.play.ServerPlayNetHandler.handleSlashCommand(ServerPlayNetHandler.java:1085) ~[?:?]
	at net.minecraft.network.play.ServerPlayNetHandler.processChatMessage(ServerPlayNetHandler.java:1065) ~[?:?]
	at net.minecraft.network.play.client.CChatMessagePacket.processPacket(CChatMessagePacket.java:40) ~[?:?]
	at net.minecraft.network.play.client.CChatMessagePacket.processPacket(CChatMessagePacket.java:8) ~[?:?]
	at net.minecraft.network.PacketThreadUtil.lambda$checkThreadAndEnqueue$0(PacketThreadUtil.java:19) ~[?:?]
	at net.minecraft.util.concurrent.TickDelayedTask.run(TickDelayedTask.java:20) ~[?:?]
	at net.minecraft.util.concurrent.ThreadTaskExecutor.run(ThreadTaskExecutor.java:139) ~[?:?]
	at net.minecraft.util.concurrent.RecursiveEventLoop.run(RecursiveEventLoop.java:22) ~[?:?]
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:763) ~[?:?]
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:157) ~[?:?]
	at net.minecraft.util.concurrent.ThreadTaskExecutor.driveOne(ThreadTaskExecutor.java:109) ~[?:?]
	at net.minecraft.server.MinecraftServer.driveOneInternal(MinecraftServer.java:746) ~[?:?]
	at net.minecraft.server.MinecraftServer.driveOne(MinecraftServer.java:740) ~[?:?]
	at net.minecraft.util.concurrent.ThreadTaskExecutor.drainTasks(ThreadTaskExecutor.java:97) ~[?:?]
	at net.minecraft.server.MinecraftServer.runScheduledTasks(MinecraftServer.java:725) ~[?:?]
	at net.minecraft.server.MinecraftServer.func_240802_v_(MinecraftServer.java:669) ~[?:?]
	at net.minecraft.server.MinecraftServer.lambda$func_240784_a_$0(MinecraftServer.java:231) ~[?:?]
	at java.lang.Thread.run(Thread.java:748) [?:1.8.0_221]
Caused by: java.lang.NullPointerException
	at net.minecraft.entity.monster.SlimeEntity.setSlimeSize(SlimeEntity.java:80) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.entity.monster.SlimeEntity.readAdditional(SlimeEntity.java:110) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	at net.minecraft.entity.Entity.read(Entity.java:1645) ~[forge-1.16.1-32.0.24_mapped_snapshot_20200514-1.16-recomp.jar:?]
	... 28 more

 

[ChampionAsh5357]

It would be good if you could show your code, that might help find the issue.

 

My guess is you didn't register MobEntity#func_233666_p_ in your FMLCommonSetupEvent for your specific entity type as that does initialize the follow range attribute with a value of 16.

[samjviana]

Actually your answer in the topic 1.16.1 Custom Entity attributes helped me a lot understanding how to work with AttributeModifierMap, and i managed to finish the entity, thank you.
Now i'm trying to change the color of the slime. instead of having a bunch of entities i want an "template" that randomize in many colors (just like it happens with leaves), so i'll have slimes of many colors, i know it's not an original idea but it's just for practice. Should i open another topic about this?
Sorry by the english by the way XD.

[ChampionAsh5357]

Sure, but if you want that, you might want to take a look at the EntitySheep code.

[samjviana]

Looking at EntitySheep code helped a lot, thanks.