A window's size and position are expressed as a bounding rectangle, given in coordinates relative to the screen or the parent window. The coordinates of a top-level window are relative to the upper left corner of the screen; the coordinates of a child window are relative to the upper left corner of the parent window. An application specifies a window's initial size and position when it creates the window, but it can change the window's size and position at any time. For more information, see Filled Shapes.
This section contains the following topics: