From 923dcec4e766314e8393c8d0926854505296e027 Mon Sep 17 00:00:00 2001
From: "Dylan K. Taylor" <dktapps@pmmp.io>
Date: Mon, 19 Dec 2022 20:57:51 +0000
Subject: [PATCH] Revert "World: do not refresh ticked chunks list every tick"

This reverts commit aebcfc516ff97492c58ee478a3944915a777a75e.

this has edge cases in the handling of adjacent chunk locks which I
didn't consider at the time. Once accounting for those edge cases, it
became significantly more complex to the point that I realized this
needed more planning.
---
 src/world/World.php | 44 +++++++++++++-------------------------------
 1 file changed, 13 insertions(+), 31 deletions(-)

diff --git a/src/world/World.php b/src/world/World.php
index a448a9b62..b20960755 100644
--- a/src/world/World.php
+++ b/src/world/World.php
@@ -160,12 +160,6 @@ class World implements ChunkManager{
 
 	public const DEFAULT_TICKED_BLOCKS_PER_SUBCHUNK_PER_TICK = 3;
 
-	/**
-	 * Ticking chunk cache is refreshed after this many ticks. Increasing this value increases the interval between
-	 * cache refreshes, which can cause longer delays before newly loaded chunks start being ticked.
-	 */
-	private const TICKING_CHUNK_CACHE_REFRESH_INTERVAL = 20;
-
 	/**
 	 * @var Player[] entity runtime ID => Player
 	 * @phpstan-var array<int, Player>
@@ -327,12 +321,6 @@ class World implements ChunkManager{
 
 	private int $chunkTickRadius;
 	private int $tickedBlocksPerSubchunkPerTick = self::DEFAULT_TICKED_BLOCKS_PER_SUBCHUNK_PER_TICK;
-	private int $tickingChunkCacheRefreshTicker = 0;
-	/**
-	 * @var true[]
-	 * @phpstan-var array<int, true>
-	 */
-	private array $tickingChunkCache = [];
 	/**
 	 * @var true[]
 	 * @phpstan-var array<int, true>
@@ -1153,8 +1141,15 @@ class World implements ChunkManager{
 		$this->chunkTickRadius = $radius;
 	}
 
-	private function selectTickedChunks() : void{
-		$this->tickingChunkCache = [];
+	private function tickChunks() : void{
+		if($this->chunkTickRadius <= 0 || count($this->tickingLoaders) === 0){
+			return;
+		}
+
+		$this->timings->randomChunkUpdatesChunkSelection->startTiming();
+
+		/** @var bool[] $chunkTickList chunkhash => dummy */
+		$chunkTickList = [];
 
 		$centerChunks = [];
 
@@ -1175,27 +1170,15 @@ class World implements ChunkManager{
 				$centerChunkZ
 			) as $hash){
 				World::getXZ($hash, $chunkX, $chunkZ);
-				if(!isset($this->tickingChunkCache[$hash]) && isset($this->chunks[$hash]) && $this->isChunkTickable($chunkX, $chunkZ)){
-					$this->tickingChunkCache[$hash] = true;
+				if(!isset($chunkTickList[$hash]) && isset($this->chunks[$hash]) && $this->isChunkTickable($chunkX, $chunkZ)){
+					$chunkTickList[$hash] = true;
 				}
 			}
 		}
-	}
 
-	private function tickChunks() : void{
-		if($this->chunkTickRadius <= 0 || count($this->tickingLoaders) === 0){
-			$this->tickingChunkCache = [];
-			return;
-		}
+		$this->timings->randomChunkUpdatesChunkSelection->stopTiming();
 
-		if(++$this->tickingChunkCacheRefreshTicker >= self::TICKING_CHUNK_CACHE_REFRESH_INTERVAL){
-			$this->tickingChunkCacheRefreshTicker = 0;
-			$this->timings->randomChunkUpdatesChunkSelection->startTiming();
-			$this->selectTickedChunks();
-			$this->timings->randomChunkUpdatesChunkSelection->stopTiming();
-		}
-
-		foreach($this->tickingChunkCache as $index => $_){
+		foreach($chunkTickList as $index => $_){
 			World::getXZ($index, $chunkX, $chunkZ);
 
 			$this->tickChunk($chunkX, $chunkZ);
@@ -2800,7 +2783,6 @@ class World implements ChunkManager{
 		unset($this->chunks[$chunkHash]);
 		unset($this->blockCache[$chunkHash]);
 		unset($this->changedBlocks[$chunkHash]);
-		unset($this->tickingChunkCache[$chunkHash]);
 
 		if(array_key_exists($chunkHash, $this->chunkPopulationRequestMap)){
 			$this->logger->debug("Rejecting population promise for chunk $x $z");