Paper/patches/server/0881-Only-tick-item-frames-if-players-can-see-it.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Redned <redned235@gmail.com>
Date: Mon, 19 Jun 2023 15:45:53 -0500
Subject: [PATCH] Only tick item frames if players can see it

In the event that an item frame cannot be seen by any players, ticking the item frame every tick is unnecessary. This can be a very hot section of the entity tracker when lots of item frames are present on a server, so this reduces the logic which speeds it up.

diff --git a/src/main/java/net/minecraft/server/level/ServerEntity.java b/src/main/java/net/minecraft/server/level/ServerEntity.java
index 3608257fabec6ad7edb056def8a6f36c50b4871e..1f0931bdd4d82c05d7b5f8b8e5c2cc6d23905c73 100644
--- a/src/main/java/net/minecraft/server/level/ServerEntity.java
+++ b/src/main/java/net/minecraft/server/level/ServerEntity.java
@@ -111,7 +111,7 @@ public class ServerEntity {
 
         Entity entity = this.entity;
 
-        if (entity instanceof ItemFrame) {
+        if (!this.trackedPlayers.isEmpty() && entity instanceof ItemFrame) { // Paper - Perf: Only tick item frames if players can see it
             ItemFrame entityitemframe = (ItemFrame) entity;
 
             if (true || this.tickCount % 10 == 0) { // CraftBukkit - Moved below, should always enter this block