From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: MrHua269 <wangxyper@163.com>
Date: Sun, 12 Jan 2025 15:37:25 +0800
Subject: [PATCH] SparklyPaper Skip "distanceToSqr" call in
 "ServerEntity#sendChanges" if the delta movement hasn't changed


diff --git a/net/minecraft/server/level/ServerEntity.java b/net/minecraft/server/level/ServerEntity.java
index 0fb253aa55a24b56b17f524b3261c5b75c7d7e59..1de43a4969a2a4535239b15a7bc30d99eb6934c6 100644
--- a/net/minecraft/server/level/ServerEntity.java
+++ b/net/minecraft/server/level/ServerEntity.java
@@ -195,6 +195,8 @@ public class ServerEntity {
 
                 if (this.entity.hasImpulse || this.trackDelta || this.entity instanceof LivingEntity && ((LivingEntity)this.entity).isFallFlying()) {
                     Vec3 deltaMovement = this.entity.getDeltaMovement();
+
+                    if (deltaMovement != this.lastSentMovement) { // SparklyPaper start - skip distanceToSqr call in ServerEntity#sendChanges if the delta movement hasn't changed
                     double d = deltaMovement.distanceToSqr(this.lastSentMovement);
                     if (d > 1.0E-7 || d > 0.0 && deltaMovement.lengthSqr() == 0.0) {
                         this.lastSentMovement = deltaMovement;
@@ -212,6 +214,7 @@ public class ServerEntity {
                             this.broadcast.accept(new ClientboundSetEntityMotionPacket(this.entity.getId(), this.lastSentMovement));
                         }
                     }
+                    } // SparklyPaper end
                 }
 
                 if (packet != null) {