(gobject:define-genum "GtkContentFit" content-fit
  (:export t
   :type-initializer "gtk_content_fit_get_type")
  (:fill 0)
  (:contain 1)
  (:cover 2)
  (:scale-down 3))  

:fill

Make the content fill the entire allocation, without taking its aspect ratio in consideration. The resulting content will appear as stretched if its aspect ratio is different from the allocation aspect ratio.

:contain

Scale the content to fit the allocation, while taking its aspect ratio in consideration. The resulting content will appear as letterboxed if its aspect ratio is different from the allocation aspect ratio.

:cover

Cover the entire allocation, while taking the content aspect ratio in consideration. The resulting content will appear as clipped if its aspect ratio is different from the allocation aspect ratio.

:scale-down

The content is scaled down to fit the allocation, if needed, otherwise its original size is used.