gtk:graphics-offload-black-background (object)

object -- a gtk:graphics-offload widget
setting -- a boolean whether to draw a black background behind the content

Accessor of the black-background slot of the gtk:graphics-offload class. The gtk:graphics-offload-black-background function returns whether the widget draws a black background. The (setf gtk:graphics-offload-black-background) function sets whether object will draw a black background.

A main use case for this is letterboxing where black bars are visible next to the content if the aspect ratio of the content does not match the dimensions of the monitor. Using this property for letterboxing instead of CSS allows compositors to show content with maximum efficiency, using direct scanout to avoid extra copies in the compositor.

On Wayland, this is implemented using the single-pixel buffer protocol.

Since 4.16