Implemented partial chunk saving on LevelDB (#3078)

src/world/SimpleChunkManager.php

@@ -61,7 +61,7 @@ class SimpleChunkManager implements ChunkManager{
 	public function setBlockAt(int $x, int $y, int $z, Block $block) : void{
 		if($this->terrainPointer->moveTo($x, $y, $z, true)){
 			$this->terrainPointer->currentSubChunk->setFullBlock($x & 0xf, $y & 0xf, $z & 0xf, $block->getFullId());
-			$this->terrainPointer->currentChunk->setChanged(true);
+			$this->terrainPointer->currentChunk->setDirtyFlag(Chunk::DIRTY_FLAG_TERRAIN, true);
 		}else{
 			throw new \InvalidArgumentException("Cannot set block at coordinates x=$x,y=$y,z=$z, terrain is not loaded or out of bounds");
 		}

src/world/World.php

@@ -1038,9 +1038,9 @@ class World implements ChunkManager{
 		$this->timings->syncChunkSaveTimer->startTiming();
 		try{
 			foreach($this->chunks as $chunk){
-				if($chunk->hasChanged() and $chunk->isGenerated()){
+				if($chunk->isDirty() and $chunk->isGenerated()){
 					$this->provider->saveChunk($chunk);
-					$chunk->setChanged(false);
+					$chunk->clearDirtyFlags();
 				}
 			}
 		}finally{
@@ -2213,7 +2213,7 @@ class World implements ChunkManager{
 
 		unset($this->blockCache[$chunkHash]);
 		unset($this->changedBlocks[$chunkHash]);
-		$chunk->setChanged();
+		$chunk->setDirty();
 
 		if(!$this->isChunkInUse($chunkX, $chunkZ)){
 			$this->unloadChunkRequest($chunkX, $chunkZ);
@@ -2505,7 +2505,7 @@ class World implements ChunkManager{
 				return false;
 			}
 
-			if($trySave and $this->getAutoSave() and $chunk->isGenerated() and $chunk->hasChanged()){
+			if($trySave and $this->getAutoSave() and $chunk->isGenerated() and $chunk->isDirty()){
 				$this->timings->syncChunkSaveTimer->startTiming();
 				try{
 					$this->provider->saveChunk($chunk);

src/world/format/Chunk.php

@@ -46,6 +46,10 @@ use function str_repeat;
 use function strlen;
 
 class Chunk{
+	public const DIRTY_FLAG_TERRAIN = 1 << 0;
+	public const DIRTY_FLAG_ENTITIES = 1 << 1;
+	public const DIRTY_FLAG_TILES = 1 << 2;
+	public const DIRTY_FLAG_BIOMES = 1 << 3;
 
 	public const MAX_SUBCHUNKS = 16;
 
@@ -54,8 +58,8 @@ class Chunk{
 	/** @var int */
 	protected $z;
 
-	/** @var bool */
+	/** @var int */
-	protected $hasChanged = false;
+	private $dirtyFlags = 0;
 
 	/** @var bool */
 	protected $lightPopulated = false;
@@ -189,7 +193,7 @@ class Chunk{
 	 */
 	public function setFullBlock(int $x, int $y, int $z, int $block) : void{
 		$this->getSubChunk($y >> 4, true)->setFullBlock($x, $y & 0xf, $z, $block);
-		$this->hasChanged = true;
+		$this->dirtyFlags |= self::DIRTY_FLAG_TERRAIN;
 	}
 
 	/**
@@ -396,8 +400,8 @@ class Chunk{
 	 * @param int $biomeId 0-255
 	 */
 	public function setBiomeId(int $x, int $z, int $biomeId) : void{
-		$this->hasChanged = true;
 		$this->biomeIds[($z << 4) | $x] = chr($biomeId & 0xff);
+		$this->dirtyFlags |= self::DIRTY_FLAG_BIOMES;
 	}
 
 	/**
@@ -451,7 +455,7 @@ class Chunk{
 		}
 		$this->entities[$entity->getId()] = $entity;
 		if(!($entity instanceof Player)){
-			$this->hasChanged = true;
+			$this->dirtyFlags |= self::DIRTY_FLAG_ENTITIES;
 		}
 	}
 
@@ -461,7 +465,7 @@ class Chunk{
 	public function removeEntity(Entity $entity) : void{
 		unset($this->entities[$entity->getId()]);
 		if(!($entity instanceof Player)){
-			$this->hasChanged = true;
+			$this->dirtyFlags |= self::DIRTY_FLAG_ENTITIES;
 		}
 	}
 
@@ -478,7 +482,7 @@ class Chunk{
 			$this->tiles[$index]->close();
 		}
 		$this->tiles[$index] = $tile;
-		$this->hasChanged = true;
+		$this->dirtyFlags |= self::DIRTY_FLAG_TILES;
 	}
 
 	/**
@@ -487,7 +491,7 @@ class Chunk{
 	public function removeTile(Tile $tile) : void{
 		$pos = $tile->getPos();
 		unset($this->tiles[Chunk::blockHash($pos->x, $pos->y, $pos->z)]);
-		$this->hasChanged = true;
+		$this->dirtyFlags |= self::DIRTY_FLAG_TILES;
 	}
 
 	/**
@@ -563,7 +567,7 @@ class Chunk{
 	 */
 	public function initChunk(World $world) : void{
 		if($this->NBTentities !== null){
-			$this->hasChanged = true;
+			$this->dirtyFlags |= self::DIRTY_FLAG_ENTITIES;
 			$world->timings->syncChunkLoadEntitiesTimer->startTiming();
 			foreach($this->NBTentities as $nbt){
 				if($nbt instanceof CompoundTag){
@@ -584,7 +588,7 @@ class Chunk{
 			$world->timings->syncChunkLoadEntitiesTimer->stopTiming();
 		}
 		if($this->NBTtiles !== null){
-			$this->hasChanged = true;
+			$this->dirtyFlags |= self::DIRTY_FLAG_TILES;
 			$world->timings->syncChunkLoadTileEntitiesTimer->startTiming();
 			foreach($this->NBTtiles as $nbt){
 				if($nbt instanceof CompoundTag){
@@ -619,15 +623,35 @@ class Chunk{
 	/**
 	 * @return bool
 	 */
-	public function hasChanged() : bool{
+	public function isDirty() : bool{
-		return $this->hasChanged or !empty($this->tiles) or !empty($this->getSavableEntities());
+		return $this->dirtyFlags !== 0 or !empty($this->tiles) or !empty($this->getSavableEntities());
+	}
+
+	public function getDirtyFlag(int $flag) : bool{
+		return ($this->dirtyFlags & $flag) !== 0;
 	}
 
 	/**
-	 * @param bool $value
+	 * @return int
 	 */
-	public function setChanged(bool $value = true) : void{
+	public function getDirtyFlags() : int{
-		$this->hasChanged = $value;
+		return $this->dirtyFlags;
+	}
+
+	public function setDirtyFlag(int $flag, bool $value) : void{
+		if($value){
+			$this->dirtyFlags |= $flag;
+		}else{
+			$this->dirtyFlags &= ~$flag;
+		}
+	}
+
+	public function setDirty() : void{
+		$this->dirtyFlags = ~0;
+	}
+
+	public function clearDirtyFlags() : void{
+		$this->dirtyFlags = 0;
 	}
 
 	/**
@@ -666,7 +690,7 @@ class Chunk{
 		}else{
 			$this->subChunks[$y] = $subChunk;
 		}
-		$this->hasChanged = true;
+		$this->setDirtyFlag(self::DIRTY_FLAG_TERRAIN, true);
 		return true;
 	}
 

src/world/format/io/FormatConverter.php

@@ -135,6 +135,7 @@ class FormatConverter{
 		$thisRound = $start;
 		static $reportInterval = 256;
 		foreach($this->oldProvider->getAllChunks(true, $this->logger) as $chunk){
+			$chunk->setDirty();
 			$new->saveChunk($chunk);
 			$counter++;
 			if(($counter % $reportInterval) === 0){

src/world/format/io/leveldb/LevelDB.php

@@ -416,7 +416,9 @@ class LevelDB extends BaseWorldProvider implements WritableWorldProvider{
 
 		$chunk->setGenerated();
 		$chunk->setPopulated();
-		$chunk->setChanged($hasBeenUpgraded); //trigger rewriting chunk to disk if it was converted from an older format
+		if($hasBeenUpgraded){
+			$chunk->setDirty(); //trigger rewriting chunk to disk if it was converted from an older format
+		}
 
 		return $chunk;
 	}
@@ -431,39 +433,43 @@ class LevelDB extends BaseWorldProvider implements WritableWorldProvider{
 		$write = new \LevelDBWriteBatch();
 		$write->put($index . self::TAG_VERSION, chr(self::CURRENT_LEVEL_CHUNK_VERSION));
 
-		$subChunks = $chunk->getSubChunks();
+		if($chunk->getDirtyFlag(Chunk::DIRTY_FLAG_TERRAIN)){
-		foreach($subChunks as $y => $subChunk){
+			$subChunks = $chunk->getSubChunks();
-			$key = $index . self::TAG_SUBCHUNK_PREFIX . chr($y);
+			foreach($subChunks as $y => $subChunk){
-			if($subChunk->isEmpty(false)){ //MCPE doesn't save light anymore as of 1.1
+				$key = $index . self::TAG_SUBCHUNK_PREFIX . chr($y);
-				$write->delete($key);
+				if($subChunk->isEmpty(false)){ //MCPE doesn't save light anymore as of 1.1
-			}else{
+					$write->delete($key);
-				$subStream = new BinaryStream();
+				}else{
-				$subStream->putByte(self::CURRENT_LEVEL_SUBCHUNK_VERSION);
+					$subStream = new BinaryStream();
+					$subStream->putByte(self::CURRENT_LEVEL_SUBCHUNK_VERSION);
 
-				$layers = $subChunk->getBlockLayers();
+					$layers = $subChunk->getBlockLayers();
-				$subStream->putByte(count($layers));
+					$subStream->putByte(count($layers));
-				foreach($layers as $blocks){
+					foreach($layers as $blocks){
-					$subStream->putByte($blocks->getBitsPerBlock() << 1);
+						$subStream->putByte($blocks->getBitsPerBlock() << 1);
-					$subStream->put($blocks->getWordArray());
+						$subStream->put($blocks->getWordArray());
 
-					$palette = $blocks->getPalette();
+						$palette = $blocks->getPalette();
-					$subStream->putLInt(count($palette));
+						$subStream->putLInt(count($palette));
-					$tags = [];
+						$tags = [];
-					foreach($palette as $p){
+						foreach($palette as $p){
-						$tags[] = new TreeRoot(CompoundTag::create()
+							$tags[] = new TreeRoot(CompoundTag::create()
-							->setString("name", $idMap[$p >> 4] ?? "minecraft:info_update")
+								->setString("name", $idMap[$p >> 4] ?? "minecraft:info_update")
-							->setInt("oldid", $p >> 4) //PM only (debugging), vanilla doesn't have this
+								->setInt("oldid", $p >> 4) //PM only (debugging), vanilla doesn't have this
-							->setShort("val", $p & 0xf));
+								->setShort("val", $p & 0xf));
+						}
+
+						$subStream->put((new LittleEndianNbtSerializer())->writeMultiple($tags));
 					}
 
-					$subStream->put((new LittleEndianNbtSerializer())->writeMultiple($tags));
+					$write->put($key, $subStream->getBuffer());
 				}
-
-				$write->put($key, $subStream->getBuffer());
 			}
 		}
 
-		$write->put($index . self::TAG_DATA_2D, str_repeat("\x00", 512) . $chunk->getBiomeIdArray());
+		if($chunk->getDirtyFlag(Chunk::DIRTY_FLAG_BIOMES)){
+			$write->put($index . self::TAG_DATA_2D, str_repeat("\x00", 512) . $chunk->getBiomeIdArray());
+		}
 
 		//TODO: use this properly
 		$write->put($index . self::TAG_STATE_FINALISATION, chr(self::FINALISATION_DONE));

src/world/generator/PopulationTask.php

@@ -118,7 +118,7 @@ class PopulationTask extends AsyncTask{
 		foreach($chunks as $i => $c){
 			if($c !== null){
 				$c = $chunks[$i] = $manager->getChunk($c->getX(), $c->getZ());
-				if(!$c->hasChanged()){
+				if(!$c->isDirty()){
 					$chunks[$i] = null;
 				}
 			}else{