Question Rendering UI to a separate camera causes squashing and stretching when window resizing

In my 2D project, I have a cinemachine setup with a pixel perfect camera. This camera is set to "Windowbox" mode, as this gives me the desired results of creating black bars on the top/bottom and left/right of the screen if the user resizes the main game window. This works perfectly.

However, the UI is a different story. I want my UI to stick to the game view only, and not go beyond the game view and into the black bars. To solve this problem, I decided to add a second camera that only renders the UI. On my main camera, I have this second camera in the stack as an "overlay" camera.

This does seem to work, but with a drawback I was not expecting. When the user resizes the game window, the UI will squash or stretch, depending on how the user resized that window. Obviously, this is unwanted behavior, so I was wondering how I could solve this problem.

I tried rendering everything with one camera, and setting my canvas to "screen space - overlay", which also.. works, but with unwanted behavior, as well.

Doing it this way gives me pixel shifting on the UI elements. Here's a preview of that -




If I could get rid of this pixel shifting, this way of doing it (using one camera) would be ideal. However, rendering the UI to a second camera seems like a better approach. I just need to get rid of the squash and stretch during a game window resize.

Here are my canvas settings when using the second camera to render the UI -



Is there any way to get rid of this squash/stretch when using a separate camera set to overlay, or perhaps get rid of the pixel shifting when using one camera that has the pixel perfect component?

 

Alright, so I managed to solve this issue. For anyone else who runs into this - I've added the pixel perfect component to the second camera, again set to "Windowbox" mode.

However, this might be an issue, as Unity gives me a warning that says the pixel perfect component won't function properly if stacked with another camera.

It does work, though.. for now. It completely gets rid of the pixel shifting behavior I was seeing with just one camera, and it resolves the stretching/squashing behavior I was seeing with this second camera set to overlay and rendering only the UI.

However, I can't help but think I'm overlooking something, and perhaps there's a better solution here?

Either way, this seems to work exactly how I need it to, with no odd behavior from the UI, which is excellent.