Retrieves the region that is currently being repainted.
After a call to [method@Gdk.DrawContext.begin_frame] this function will
return a union of the region passed to that function and the area of the
surface that the @context determined needs to be repainted.
If @context is not in between calls to [method@Gdk.DrawContext.begin_frame]
and [method@Gdk.DrawContext.end_frame], %NULL will be returned.
Retrieves the region that is currently being repainted.
After a call to [method@Gdk.DrawContext.begin_frame] this function will return a union of the region passed to that function and the area of the surface that the @context determined needs to be repainted.
If @context is not in between calls to [method@Gdk.DrawContext.begin_frame] and [method@Gdk.DrawContext.end_frame], %NULL will be returned.