From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Samsuik <40902469+Samsuik@users.noreply.github.com>
Date: Thu, 30 Nov 2023 15:54:49 +0000
Subject: [PATCH] Reduce entity tracker player updates


diff --git a/src/main/java/net/minecraft/server/level/ChunkMap.java b/src/main/java/net/minecraft/server/level/ChunkMap.java
index b2c99286e89f7f04aaa6efed245d344f15aa35fb..925809750c80a74d80255f6b611c486915530b34 100644
--- a/src/main/java/net/minecraft/server/level/ChunkMap.java
+++ b/src/main/java/net/minecraft/server/level/ChunkMap.java
@@ -927,7 +927,11 @@ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider
             if (tracker == null) {
                 continue;
             }
+            // Sakura start - reduce entity tracker player updates
+            if (tracker.shouldUpdatePlayers()) {
             ((ca.spottedleaf.moonrise.patches.entity_tracker.EntityTrackerTrackedEntity)tracker).moonrise$tick(nearbyPlayers.getChunk(entity.chunkPosition()));
+            }
+            // Sakura end - reduce entity tracker player updates
             tracker.serverEntity.sendChanges();
         }
 
@@ -1179,12 +1183,30 @@ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider
             }
         }
         // Paper end - optimise entity tracker
+        // Sakura start - reduce entity tracker player updates
+        private final int playerUpdateInterval;
+        private Vec3 entityPosition;
+
+        public final boolean shouldUpdatePlayers() {
+            // We have to always update players otherwise they can turn invisible on teleports (why?)
+            if (this.entity instanceof net.minecraft.world.entity.player.Player || this.entity.tickCount % this.playerUpdateInterval == 0) {
+                return true;
+            }
+
+            Vec3 lastPosition = this.entityPosition;
+            this.entityPosition = this.entity.position();
+
+            return this.entity.position().distanceToSqr(lastPosition) >= (double) this.range / 2.0;
+        }
+        // Sakura start - reduce entity tracker player updates
 
         public TrackedEntity(final Entity entity, final int i, final int j, final boolean flag) {
             this.serverEntity = new ServerEntity(ChunkMap.this.level, entity, j, flag, this::broadcast, this.seenBy); // CraftBukkit
             this.entity = entity;
             this.range = i;
             this.lastSectionPos = SectionPos.of((EntityAccess) entity);
+            this.playerUpdateInterval = Math.min(j, 20); // Sakura - reduce entity tracker player updates
+            this.entityPosition = entity.position(); // Sakura - reduce entity tracker player updates
         }
 
         public boolean equals(Object object) {