PaperMC/patches/server/0446-MC-4-Fix-item-position-desync.patch
Jake Potrebic c6aa61ee18
Updated Upstream (Bukkit/CraftBukkit/Spigot) (#11561)
Updated Upstream (Bukkit/CraftBukkit/Spigot)

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:
b9df8e9f SPIGOT-7933: Improve custom Minecart max speed
fc496179 Fix InstrumentTest
7c0ec598 PR-1075: Make Art an interface
c389f5a4 PR-1074: Make Sound an interface

CraftBukkit Changes:
df1efc0bb SPIGOT-7945: `Bukkit#dispatchCommand` throws `UnsupportedOperationException`
285df6e85 SPIGOT-7933: Improve custom Minecart max speed
a0f3d4e50 SPIGOT-7940: Recipe book errors after reload
9e0618ec2 SPIGOT-7937: Cannot spawn minecart during world generation with minecart_improvements enabled
1eb4d28da SPIGOT-7941: Fix resistance over 4 amplify causing issues in damage
52b99158a PR-1504: Make Art an interface
e18ae35f1 PR-1502: Make Sound an interface

Spigot Changes:
e65d67a7 SPIGOT-7934: Item entities start "bouncing" under certain conditions
2024-11-04 18:42:38 +01:00

50 lines
2.5 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 488ebd443903af812913437f1ade3002093f2470..a043ac10834562d357ef0b5aded2e916e2a0d056 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 * 4096.0);
+ return Math.round(value * 4096.0); // Paper - Fix MC-4; diff on change
}
@VisibleForTesting
static double decode(long value) {
- return (double)value / 4096.0;
+ return value / 4096.0; // Paper - Fix MC-4; 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 9ebce90de425989014466d2c5ce68fce505d1dcd..282863951033f7e036b0e58393651e1a22fada23 100644
--- a/src/main/java/net/minecraft/world/entity/Entity.java
+++ b/src/main/java/net/minecraft/world/entity/Entity.java
@@ -4479,6 +4479,16 @@ public abstract class Entity implements SyncedDataHolder, Nameable, EntityAccess
return;
}
// Paper end - Block invalid positions and bounding box
+ // 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 * 4096.0) * (1 / 4096.0);
+ y = Mth.lfloor(y * 4096.0) * (1 / 4096.0);
+ z = Mth.lfloor(z * 4096.0) * (1 / 4096.0);
+ }
+ }
+ // 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);