pocketmine\level\SimpleChunkManager::setChunk PHP Метод

    public function setChunk(int $chunkX, int $chunkZ, FullChunk $chunk = null)
    {
        if ($chunk === null) {
            unset($this->chunks[Level::chunkHash($chunkX, $chunkZ)]);
            return;
        }
        $this->chunks[Level::chunkHash($chunkX, $chunkZ)] = $chunk;
    }