Postprocessing on non full screen camera - builtin pipeline

Hello,

I am using the builtin render pipeline.

I am targeting 16:9 aspect ratio so I am using letterboxing, and handling this by changing the viewport rect of the camera.

The problem occurs when I use post processing on this camera, I recieve this warning:

When used with builtin render pipeline, Postprocessing package expects to be used on a fullscreen Camera.
Please note that using Camera viewport may result in visual artefacts or some things not working.
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There is a huge performance loss on the unity editor and build.

Is there any suggestion I can follow? Is it possible to letterbox properly without changing the viewport of the camera?

Thanks

 

Easiest solution would be to render to a rendertexture that has the letterboxed aspect ratio, and then draw that. A lot of things don't work with a non-standard viewport (e.g. deferred rendering).