Awesome
Portals VR
Unity Version 2018.2.7f1 (not confident if it works on 2018.3)
This produces a 3D effect, not a 2d image:
(Click the image to view a video on youtube) ^
Made a simple interior model as I'm mainly trying to get the effect working
Use this project all you want, you can even use my TARDIS model for whatever your needs are.