Paper/patches/server/0522-MC-4-Fix-item-position-desync.patch
Jake Potrebic 38be4f873b
Updated Upstream (Bukkit/CraftBukkit/Spigot) (#9018)
Upstream has released updates that appear to apply and compile correctly.
This update has not been tested by PaperMC and as with ANY update, please do your own testing

Bukkit Changes:
2c64d8c4 SPIGOT-7309: Add API for jukebox inventories
a6d7e4ca PR-826: Add Sniffer API

CraftBukkit Changes:
93813509b SPIGOT-7309: Add API for jukebox inventories
2d5209e8d PR-1153: Handle teleport reason in spreadplayers command
f5b61387e SPIGOT-7308: Fix NullPointerException when calling Jukebox#setRecord()
388d458a6 SPIGOT-7306: Fix reset of coords in default teleportTo in EntityPlayer
40b87e1af PR-1150: Add Sniffer API and handle EntityItemDropEvent

Spigot Changes:
6ad4b93c SPIGOT-7298: Fix debug stick always permission left click toggle
2023-03-24 13:38:40 -07:00

51 lines
2.4 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: BillyGalbreath <blake.galbreath@gmail.com>
Date: Tue, 8 Dec 2020 20:24:52 -0600
Subject: [PATCH] MC-4: Fix item position desync
This fixes item position desync (MC-4) by running the item coordinates
through the encode/decode methods of the packet that causes the precision
loss, which forces the server to lose the same precision as the client
keeping them in sync.
diff --git a/src/main/java/net/minecraft/network/protocol/game/VecDeltaCodec.java b/src/main/java/net/minecraft/network/protocol/game/VecDeltaCodec.java
index 5ca3ad7b3d7606accd0a58b3c708fadb349608f7..4b6e0fe2fabcc55007fd8979e81f66df9c0278b7 100644
--- a/src/main/java/net/minecraft/network/protocol/game/VecDeltaCodec.java
+++ b/src/main/java/net/minecraft/network/protocol/game/VecDeltaCodec.java
@@ -9,12 +9,12 @@ public class VecDeltaCodec {
@VisibleForTesting
static long encode(double value) {
- return Math.round(value * 4096.0D);
+ return Math.round(value * 4096.0D); // Paper - diff on change
}
@VisibleForTesting
static double decode(long value) {
- return (double)value / 4096.0D;
+ return (double)value / 4096.0D; // Paper - diff on change
}
public Vec3 decode(long x, long y, long z) {
diff --git a/src/main/java/net/minecraft/world/entity/Entity.java b/src/main/java/net/minecraft/world/entity/Entity.java
index 443bf4c32105a88efbb4df0b8b803cb39ee8b751..d1eb347b80fcee37f59012505dd0ae5787f95d7b 100644
--- a/src/main/java/net/minecraft/world/entity/Entity.java
+++ b/src/main/java/net/minecraft/world/entity/Entity.java
@@ -4099,6 +4099,16 @@ public abstract class Entity implements Nameable, EntityAccess, CommandSource {
return;
}
// Paper end - rewrite chunk system
+ // Paper start - fix MC-4
+ if (this instanceof ItemEntity) {
+ if (io.papermc.paper.configuration.GlobalConfiguration.get().misc.fixEntityPositionDesync) {
+ // encode/decode from ClientboundMoveEntityPacket
+ x = Mth.lfloor(x * 4096.0D) * (1 / 4096.0D);
+ y = Mth.lfloor(y * 4096.0D) * (1 / 4096.0D);
+ z = Mth.lfloor(z * 4096.0D) * (1 / 4096.0D);
+ }
+ }
+ // Paper end - fix MC-4
if (this.position.x != x || this.position.y != y || this.position.z != z) {
this.position = new Vec3(x, y, z);
int i = Mth.floor(x);