AR Direction plane is not straight?

[Parameshvadivel]

Here i m trying to draw line in ar. In art.scnassets folder i have created scnbox to show as line and changes value in meterpernode in code. box node are not in straight. Here is the my output screen https://drive.google.com/file/d/1A_hQUGCFAquwapWTdEbu6nOwOwwMQr2D/view?usp=sharing

How can i show scnbox in straight? #