Camera Viewport Shape

Hello,

This question seems to have been asked a lot, but it is hard to find a satisfying answer through searching.

My goal is to have a camera viewport in the middle of my screen such that the corners of the viewport are rounded. My understanding is that this can be done using render textures, but I'm confused how to do this on the gui in the shape I want (I don't want to use a mesh if possible).

Is there an easy way to create a render texture that has rounded corners and display it on a gui?

If there is no easy way, I may just create another 2d texture that sits on top of the camera view and rounds the corners out that way instead.