The position of these objects is specified as the sum of two independent components: an external component which gives the position of a base reference point for the list of objects, and an internal component which gives the relative offset of a specific object to the base reference point. The external component is used to position the object list within the display element. For objects drawn indirectly by attaching them to a menu, gadget or requester, this is always a point within the menu, gadget or requester (the top left corner). For objects drawn directly with the DrawImage(), DrawBorder() or PrintIText() functions, specific x and y coordinates are provided as arguments that specify an offset within the screen's or window's RastPort at which to display the list of objects. Each object also has an internal, relative component that is added to the external component described above to determine the final position of the object. This allows the application to reuse a graphical object and have it appear relative to each object to which it is attached. For example, if the application has numerous gadgets of the same size, it can use a single Border structure to draw lines around all the gadgets. When the gadgets are drawn, the base position of the lines will be taken from each specific gadget in turn.
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