pocketmine\level\Level::sendChunkFromCache PHP Method

    private function sendChunkFromCache($x, $z)
    {
        if (isset($this->chunkSendTasks[$index = Level::chunkHash($x, $z)])) {
            foreach ($this->chunkSendQueue[$index] as $player) {
                /** @var Player $player */
                if ($player->isConnected() and isset($player->usedChunks[$index])) {
                    $player->sendChunk($x, $z, $this->chunkCache[$index]);
                }
            }
            unset($this->chunkSendQueue[$index]);
            unset($this->chunkSendTasks[$index]);
        }
    }