I wonder if there is a way to get the actual viewport size (width and height) in pixels. This will be very interesting to get a proportion number.
Sometimes when you orb in User Perspective mode for modeling or shading, you get a very convincing view of the scene as you view it in the viewport. Then you can create a cemera from the view but you never get the exact view, because the created camera has diferent width and height proportions than the viewport.
Getting the appropiate pixels from viewport will give a proportion to apply to the new created camera and will give the exact view as the viewport. Am I correct?
Then an addon should be created to enable this proportion when creating the new camera.