From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: NONPLAYT <76615486+NONPLAYT@users.noreply.github.com>
Date: Sat, 1 Feb 2025 19:50:02 +0300
Subject: [PATCH] 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 b6053158f5d9b6ad325ea075ab7c60f9966ba496..c7ad6bf5dd8cb8a27de3e3ed82c6eefaa36c5c08 100644
--- a/net/minecraft/server/level/ServerEntity.java
+++ b/net/minecraft/server/level/ServerEntity.java
@@ -203,23 +203,27 @@ public class ServerEntity {
 
                 if (this.entity.hasImpulse || this.trackDelta || this.entity instanceof LivingEntity && ((LivingEntity)this.entity).isFallFlying()) {
                     Vec3 deltaMovement = this.entity.getDeltaMovement();
-                    double d = deltaMovement.distanceToSqr(this.lastSentMovement);
-                    if (d > 1.0E-7 || d > 0.0 && deltaMovement.lengthSqr() == 0.0) {
-                        this.lastSentMovement = deltaMovement;
-                        if (this.entity instanceof AbstractHurtingProjectile abstractHurtingProjectile) {
-                            this.broadcast
-                                .accept(
-                                    new ClientboundBundlePacket(
-                                        List.of(
-                                            new ClientboundSetEntityMotionPacket(this.entity.getId(), this.lastSentMovement),
-                                            new ClientboundProjectilePowerPacket(abstractHurtingProjectile.getId(), abstractHurtingProjectile.accelerationPower)
+                    // DivineMC start - Skip "distanceToSqr" call in "ServerEntity#sendChanges" if the delta movement hasn't changed
+                    if (deltaMovement != this.lastSentMovement) {
+                        double d = deltaMovement.distanceToSqr(this.lastSentMovement);
+                        if (d > 1.0E-7 || d > 0.0 && deltaMovement.lengthSqr() == 0.0) {
+                            this.lastSentMovement = deltaMovement;
+                            if (this.entity instanceof AbstractHurtingProjectile abstractHurtingProjectile) {
+                                this.broadcast
+                                    .accept(
+                                        new ClientboundBundlePacket(
+                                            List.of(
+                                                new ClientboundSetEntityMotionPacket(this.entity.getId(), this.lastSentMovement),
+                                                new ClientboundProjectilePowerPacket(abstractHurtingProjectile.getId(), abstractHurtingProjectile.accelerationPower)
+                                            )
                                         )
-                                    )
-                                );
-                        } else {
-                            this.broadcast.accept(new ClientboundSetEntityMotionPacket(this.entity.getId(), this.lastSentMovement));
+                                    );
+                            } else {
+                                this.broadcast.accept(new ClientboundSetEntityMotionPacket(this.entity.getId(), this.lastSentMovement));
+                            }
                         }
                     }
+                    // DivineMC end - Skip "distanceToSqr" call in "ServerEntity#sendChanges" if the delta movement hasn't changed
                 }
 
                 if (packet != null) {