PaperMC/patches/server/0845-Only-erase-allay-memory-on-non-item-targets.patch
Bjarne Koll c5a10665b8
Remove wall-time / unused skip tick protection (#11412)
Spigot still maintains some partial implementation of "tick skipping", a
practice in which the MinecraftServer.currentTick field is updated not
by an increment of one per actual tick, but instead set to
System.currentTimeMillis() / 50. This behaviour means that the tracked
tick may "skip" a tick value in case a previous tick took more than the
expected 50ms.

To compensate for this in important paths, spigot/craftbukkit
implements "wall-time". Instead of incrementing/decrementing ticks on
block entities/entities by one for each call to their tick() method,
they instead increment/decrement important values, like
an ItemEntity's age or pickupDelay, by the difference of
`currentTick - lastTick`, where `lastTick` is the value of
`currentTick` during the last tick() call.

These "fixes" however do not play nicely with minecraft's simulation
distance as entities/block entities implementing the above behaviour
would "catch up" their values when moving from a non-ticking chunk to a
ticking one as their `lastTick` value remains stuck on the last tick in
a ticking chunk and hence lead to a large "catch up" once ticked again.

Paper completely removes the "tick skipping" behaviour (See patch
"Further-improve-server-tick-loop"), making the above precautions
completely unnecessary, which also rids paper of the previous described
incompatibility with non-ticking chunks.
2024-09-19 16:36:07 +02:00

29 lines
1.7 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Bjarne Koll <lynxplay101@gmail.com>
Date: Fri, 4 Aug 2023 15:53:36 +0200
Subject: [PATCH] Only erase allay memory on non-item targets
Spigot incorrectly instanceOf checks the EntityTargetEvent#getTarget
against the internal ItemEntity type and removes the nearest wanted item
memory if said instanceOf check fails, (which is always the case)
causing allays to behave differently as they constantly loose their
target item.
This commit fixes the faulty behaviour by instance performing a check
against the CraftItem type.
diff --git a/src/main/java/net/minecraft/world/entity/ai/behavior/GoToWantedItem.java b/src/main/java/net/minecraft/world/entity/ai/behavior/GoToWantedItem.java
index bd9aa4a5443da862be3403c1941113373741a87c..2f92eb39cde7b30a894db347ca85a506d880411e 100644
--- a/src/main/java/net/minecraft/world/entity/ai/behavior/GoToWantedItem.java
+++ b/src/main/java/net/minecraft/world/entity/ai/behavior/GoToWantedItem.java
@@ -35,8 +35,9 @@ public class GoToWantedItem {
if (event.isCancelled()) {
return false;
}
- if (!(event.getTarget() instanceof ItemEntity)) {
+ if (!(event.getTarget() instanceof org.bukkit.craftbukkit.entity.CraftItem)) { // Paper - only erase allay memory on non-item targets
memoryaccessor2.erase();
+ return false; // Paper - only erase allay memory on non-item targets
}
entityitem = (ItemEntity) ((org.bukkit.craftbukkit.entity.CraftEntity) event.getTarget()).getHandle();