Paper/patches/server/1023-Fix-CraftWorld-isChunkGenerated.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

45 lines
2.3 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Jason Penilla <11360596+jpenilla@users.noreply.github.com>
Date: Tue, 18 Jun 2024 12:43:06 -0700
Subject: [PATCH] Fix CraftWorld#isChunkGenerated
The upstream implementation is returning true for non-full chunks.
diff --git a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
index 8221597951c5e768fa8af23adc1a57871c76f3a6..90d4834f97d3ba996d46493246b1947511553424 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
@@ -372,11 +372,28 @@ public class CraftWorld extends CraftRegionAccessor implements World {
@Override
public boolean isChunkGenerated(int x, int z) {
- try {
- return this.isChunkLoaded(x, z) || this.world.getChunkSource().chunkMap.read(new ChunkPos(x, z)).get().isPresent();
- } catch (InterruptedException | ExecutionException ex) {
- throw new RuntimeException(ex);
+ // Paper start - Fix this method
+ if (!Bukkit.isPrimaryThread()) {
+ return java.util.concurrent.CompletableFuture.supplyAsync(() -> {
+ return CraftWorld.this.isChunkGenerated(x, z);
+ }, world.getChunkSource().mainThreadProcessor).join();
+ }
+ ChunkAccess chunk = world.getChunkSource().getChunkAtImmediately(x, z);
+ if (chunk != null) {
+ return chunk instanceof ImposterProtoChunk || chunk instanceof net.minecraft.world.level.chunk.LevelChunk;
}
+ final java.util.concurrent.CompletableFuture<ChunkAccess> future = new java.util.concurrent.CompletableFuture<>();
+ ca.spottedleaf.moonrise.common.util.ChunkSystem.scheduleChunkLoad(
+ this.world, x, z, false, ChunkStatus.EMPTY, true, ca.spottedleaf.concurrentutil.executor.standard.PrioritisedExecutor.Priority.NORMAL, future::complete
+ );
+ world.getChunkSource().mainThreadProcessor.managedBlock(future::isDone);
+ return future.thenApply(c -> {
+ if (c != null) {
+ return c.getPersistedStatus() == ChunkStatus.FULL;
+ }
+ return false;
+ }).join();
+ // Paper end - Fix this method
}
@Override