widget defined by x, y,
width and height by calling gdkWindowInvalidateRect on the
widget's window and all its child windows. Once the main loop
becomes idle (after the current batch of events has been processed,
roughly), the window will receive expose events for the union of
all regions that have been invalidated.gtkWidgetQueueDrawArea(object, x, y, width, height)objectxywidthheightgdkWindowInvalidateRect directly, to schedule a redraw of a
GtkDrawingArea or some portion thereof.
Frequently you can just call gdkWindowInvalidateRect or
gdkWindowInvalidateRegion instead of this function. Those
functions will invalidate only a single window, instead of the
widget and all its children.
The advantage of adding to the invalidated region compared to
simply drawing immediately is efficiency; using an invalid region
ensures that you only have to redraw one time.