BlockPlaceEvent

Im makeing a plugin that if you have a specific block and place it it will spawn 10 cobble stone block under the block. How would I do the getBlock()->getLevel()->setBlock($block getX(-1)); then another
getBlock()->getLevel()->setBlock($block getX(-2)); is their anything wrong with this code

 

To do this, use:

PHP:

public function onPlace(BlockPlaceEvent $event) {
    $block = $event->getBlock();
    if($block->getId() === Block::GLASS) { // if placed block is glass
        $level = $block->getLevel();
        for($i = $block->getY() - 1; $i >= $block->getY() - 10; $i--) { // goes down 10 blocks
            $level->setBlock(new Vector3($block->getX(), $i, $block->getZ()), Block::get(4)); // places cobblestone
        }
    }
}


It will place 10 cobblestone below the placed bedrock, for example.