Computes the region of the window that is potentially visible. This does not necessarily take into account if the window is obscured by other windows, but no area outside of this region is visible.
a cairo_region_t This must be freed with Region.destroy when you are done.
Computes the region of the window that is potentially visible. This does not necessarily take into account if the window is obscured by other windows, but no area outside of this region is visible.