Paper/patches/server/0302-Fix-item-EAR-ticks.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Nassim Jahnke <nassim@njahnke.dev>
Date: Wed, 30 Oct 2024 13:51:54 +0100
Subject: [PATCH] Fix item EAR ticks

Item entities only have their gravity ticked every 4 ticks when on ground.
Fix that and also remove Spigot's arbitrary tick skipping. It's a terribly
cheap way of getting extra performance that doesn't really work at all.

diff --git a/src/main/java/net/minecraft/world/entity/item/ItemEntity.java b/src/main/java/net/minecraft/world/entity/item/ItemEntity.java
index 75ebf09777e19645eee296a9edabac39c858ffb9..c21fa55c62d97d9511e41a1e313e904330a6eee6 100644
--- a/src/main/java/net/minecraft/world/entity/item/ItemEntity.java
+++ b/src/main/java/net/minecraft/world/entity/item/ItemEntity.java
@@ -175,7 +175,7 @@ public class ItemEntity extends Entity implements TraceableEntity {
                 }
             }
 
-            if (!this.onGround() || this.getDeltaMovement().horizontalDistanceSqr() > 9.999999747378752E-6D || (this.tickCount + this.getId()) % 4 == 0) {
+            if (!this.onGround() || this.getDeltaMovement().horizontalDistanceSqr() > 9.999999747378752E-6D || (this.tickCount + this.getId()) % 4 == 0) { // Paper - Diff on change; ActivationRange immunity
                 this.move(MoverType.SELF, this.getDeltaMovement());
                 this.applyEffectsFromBlocks();
                 float f = 0.98F;
diff --git a/src/main/java/org/spigotmc/ActivationRange.java b/src/main/java/org/spigotmc/ActivationRange.java
index bd522080d17b5b470ec3ab42aa4ecc3082248c8a..84ff1210e944ea9d1ec88874d218458773e341c9 100644
--- a/src/main/java/org/spigotmc/ActivationRange.java
+++ b/src/main/java/org/spigotmc/ActivationRange.java
@@ -234,7 +234,7 @@ public class ActivationRange
     public static boolean checkIfActive(Entity entity)
     {
         // Never safe to skip fireworks or item gravity
-        if (entity instanceof FireworkRocketEntity || (entity instanceof ItemEntity && (entity.tickCount + entity.getId() + 1) % 4 == 0)) {
+        if (entity instanceof FireworkRocketEntity || (entity instanceof ItemEntity && (entity.tickCount + entity.getId()) % 4 == 0)) { // Paper - Needed for item gravity, see ItemEntity tick
             return true;
         }
 
@@ -253,11 +253,8 @@ public class ActivationRange
                 }
                 isActive = true;
             }
-            // Add a little performance juice to active entities. Skip 1/4 if not immune.
-        } else if ( !entity.defaultActivationState && entity.tickCount % 4 == 0 && !ActivationRange.checkEntityImmunities( entity ) )
-        {
-            isActive = false;
         }
+        // Paper - remove dumb tick skipping for active entities
         return isActive;
     }
 }