DrawContext.getFrameRegion

Retrieves the region that is currently being repainted.

After a call to [gdk.draw_context.DrawContext.beginFrame] 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 [gdk.draw_context.DrawContext.beginFrame] and [gdk.draw_context.DrawContext.endFrame], null will be returned.