papermc/Spigot-Server-Patches/0497-Sync-position-on-teleportation.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Sun, 3 May 2020 14:25:55 -0400
Subject: [PATCH] Sync position on teleportation

We've seen many a cases where the "last good" x/y/z is desynced from
the x/y/z that is checked for moving too fast.

Theory is that when you have multiple movement packets queued up,
and the player is teleported after the first then the 2nd and 3rd come in,
it is triggering a massive movement velocity.

This will ensure that the servers position is synchronized anytime player is teleported.

diff --git a/src/main/java/net/minecraft/server/PlayerConnection.java b/src/main/java/net/minecraft/server/PlayerConnection.java
index 02bda8bee469da7d1f845fac58f5d5a762fe76c4..a188d9f3b600e1013e31d681f9c6a8deb64ada7e 100644
--- a/src/main/java/net/minecraft/server/PlayerConnection.java
+++ b/src/main/java/net/minecraft/server/PlayerConnection.java
@@ -500,6 +500,7 @@ public class PlayerConnection implements PacketListenerPlayIn {
             this.o = this.teleportPos.x;
             this.p = this.teleportPos.y;
             this.q = this.teleportPos.z;
+            this.syncPosition(); // Paper
             if (this.player.H()) {
                 this.player.I();
             }
@@ -1271,6 +1272,7 @@ public class PlayerConnection implements PacketListenerPlayIn {
 
         this.A = this.e;
         this.player.setLocation(d0, d1, d2, f, f1);
+        this.syncPosition(); // Paper
         this.player.playerConnection.sendPacket(new PacketPlayOutPosition(d0 - d3, d1 - d4, d2 - d5, f - f2, f1 - f3, set, this.teleportAwait));
     }