I am using a mix of 2D and 3D UI in our game which works pretty well so far. For example, I have a 2D UI window with a 3D model rendered on top of it.
I am now trying to set up an UI element which is supposed to display a 3D model on a 2D background in addition to some 2D elements on top of it. I am using a 2D camera rendering the background, a 3D camera to render the model and the UI elements in 3D space. This works but of course the UI elements rendered with the 3D camera have a slightly different look and crispness than the ones with the 2D camera.
Is there any other way to render clean, crisp 2D UI elements behind as well as in front of a 3D model? Would it work to have multiple 2D UI cameras with different depths?