From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Encode42 <me@encode42.dev>
Date: Tue, 12 Jul 2022 14:16:10 -0400
Subject: [PATCH] Add toggle for RNG manipulation

Paper patches RNG maniplulation by using a shared (and locked) random source.
This comes with a performance gain, but technical players may prefer the ability to manipulate RNG.

diff --git a/src/main/java/net/minecraft/world/entity/Entity.java b/src/main/java/net/minecraft/world/entity/Entity.java
index cf7eb47706b5344fa7619aeda88c9641bda0ad42..fe0b002a8ebf2f8495bab456854483c341e6a14e 100644
--- a/src/main/java/net/minecraft/world/entity/Entity.java
+++ b/src/main/java/net/minecraft/world/entity/Entity.java
@@ -580,7 +580,7 @@ public abstract class Entity implements Nameable, EntityAccess, CommandSource {
         this.bb = Entity.INITIAL_AABB;
         this.stuckSpeedMultiplier = Vec3.ZERO;
         this.nextStep = 1.0F;
-        this.random = SHARED_RANDOM; // Paper
+        this.random = world == null || world.purpurConfig.entitySharedRandom ? SHARED_RANDOM : RandomSource.create(); // Paper // Purpur
         this.remainingFireTicks = -this.getFireImmuneTicks();
         this.fluidHeight = new Object2DoubleArrayMap(2);
         this.fluidOnEyes = new HashSet();
diff --git a/src/main/java/net/minecraft/world/entity/animal/Squid.java b/src/main/java/net/minecraft/world/entity/animal/Squid.java
index 2a2b56940cd39ca0f14dc8246b41cf6640caa3bd..31c89a6b8f766e1fd03608723c2d03f7f64e2e9b 100644
--- a/src/main/java/net/minecraft/world/entity/animal/Squid.java
+++ b/src/main/java/net/minecraft/world/entity/animal/Squid.java
@@ -46,7 +46,7 @@ public class Squid extends WaterAnimal {
 
     public Squid(EntityType<? extends Squid> type, Level world) {
         super(type, world);
-        //this.random.setSeed((long) this.getId()); // Paper - we set the random to shared, do not clobber the seed
+        if (!world.purpurConfig.entitySharedRandom) this.random.setSeed((long) this.getId()); // Paper - we set the random to shared, do not clobber the seed // Purpur
         this.tentacleSpeed = 1.0F / (this.random.nextFloat() + 1.0F) * 0.2F;
     }
 
diff --git a/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java b/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java
index 2e1da0979b9672a4361dddf97bd8359a30c4d943..7769ceb691f5563843d69463f89c3c49b095a3f4 100644
--- a/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java
+++ b/src/main/java/org/purpurmc/purpur/PurpurWorldConfig.java
@@ -206,9 +206,11 @@ public class PurpurWorldConfig {
 
     public int entityLifeSpan = 0;
     public float entityLeftHandedChance = 0.05f;
+    public boolean entitySharedRandom = true;
     private void entitySettings() {
         entityLifeSpan = getInt("gameplay-mechanics.entity-lifespan", entityLifeSpan);
         entityLeftHandedChance = (float) getDouble("gameplay-mechanics.entity-left-handed-chance", entityLeftHandedChance);
+        entitySharedRandom = getBoolean("settings.entity.shared-random", entitySharedRandom);
     }
 
     public boolean infinityWorksWithoutArrows = false;