How to make an Actor visible only in a certain area of ​​the Viewport?

[KimCheolSoon]

Hi I want to make virtual AR in my PC targeted project. For example, when I turn the AR mode on, The AR UI will show up(as if running a camcorder).
Since using AR functionality, some Actors should only be visible in the AR UI.
How can I make this?

[KimCheolSoon]

I found the way in here :

Transparent material that hides any mesh behind it?

Hello everyone! I’d like to make a translucent material with “Disable Depth Test” ticked on for an optical illusion during gameplay. You wouldn’t be able to see it, but the player character gets hidden if they are behind it (sort of like an invisibility cloak). For example, if this material was on a sphere just floating in the middle of a room and then the player stops behind it, it’d look like the player model has a hole in their chest. Hope that makes sense! Thanks a lot in advance for the …

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