This seems like a feature a lot of driving games would want. Sorry if I missed the answer.
I know you can use video-textures to make mirrors, but for my game the mirror doesn’t need to move in relation to the screen, and it’s fine if it’s rectangular. So I thought just using a viewport with a rear-facing camera would work. The problem with this is that the image in the mirror is not mirrored!
So all I need to do is flip the viewport L-R and I’ll be in business. Does anyone know how to do that? Or, is there a better (performance-wise) way to have a rear-view mirror?