I would like to be able to make a portal effect in Blender 2.8. The idea is that you can look through a 'window' from one world to another. This could be achieved by looking between 2 scenes, or 2 view layers, I don't mind how it works.
I know this question has been asked previously but from what I can gather, the 2.8 update means that previous solutions no longer work. I have seen and tried the following solutions with no luck.
(the last one is harder to follow instructions wise)
Perhaps one of these solutions still works and I am missing a step but no matter what combination of steps I take, the 'window' (item with the holdout shader) always looks through both scenes or view layers rather than looking from one onto another. If it needs to happen in cycles that is also fine, I have tried all of the above in both cycles and eevee.
If anyone has successfully achieved this I would really appreciate a detailed step by step approach to implementing this effect.