Screen.listVisuals
gdk.visual.Visual[] listVisuals()Lists the available visuals for the specified screen. A visual describes a hardware image data format. For example, a visual might support 24-bit color, or 8-bit color, and might expect pixels to be in a certain format.
Call [glib.list.List.free] on the return value when you’re finished with it.
Returns
a list of visuals; the list must be freed, but not its contents