From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Spottedleaf <Spottedleaf@users.noreply.github.com>
Date: Sun, 25 Jun 2023 13:57:30 -0700
Subject: [PATCH] Sync vehicle position to player position on player data load

This allows the player to be re-positioned before logging into
the world without causing thread checks to trip on Folia.

diff --git a/net/minecraft/server/level/ServerPlayer.java b/net/minecraft/server/level/ServerPlayer.java
index 3d70e4daddd81c96546a4fc84086bc9e81bc3915..8ecdf803e1489375bc9dd955cd6031de724463f9 100644
--- a/net/minecraft/server/level/ServerPlayer.java
+++ b/net/minecraft/server/level/ServerPlayer.java
@@ -753,8 +753,18 @@ public class ServerPlayer extends Player implements ca.spottedleaf.moonrise.patc
         Optional<ValueInput> optional = input.child("RootVehicle");
         if (!optional.isEmpty()) {
             ServerLevel serverLevel = this.level();
+            Vec3 playerPos = this.position(); // Paper - force sync root vehicle to player position
             Entity entity = EntityType.loadEntityRecursive(
-                optional.get().childOrEmpty("Entity"), serverLevel, EntitySpawnReason.LOAD, entity2 -> !serverLevel.addWithUUID(entity2, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.MOUNT) ? null : entity2 // Paper - Entity#getEntitySpawnReason
+                    // Paper start - force sync root vehicle to player position
+                    optional.get().childOrEmpty("Entity"), serverLevel, EntitySpawnReason.LOAD, (Entity entity2) -> {
+                        // Paper start - force sync root vehicle to player position
+                        if (entity2.distanceToSqr(ServerPlayer.this) > (5.0 * 5.0)) {
+                            entity2.setPosRaw(playerPos.x, playerPos.y, playerPos.z, true);
+                        }
+                        // Paper end - force sync root vehicle to player position
+                        return !serverLevel.addWithUUID(entity2, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.MOUNT) ? null : entity2; // Paper - Entity#getEntitySpawnReason
+                    }
+                    // Paper end - force sync root vehicle to player position
             );
             if (entity != null) {
                 UUID uuid = optional.get().read("Attach", UUIDUtil.CODEC).orElse(null);