Linux Windows 
 These constants define which coordinate system a point is located in.
[scriptable, uuid(c9fbdf10-619e-436f-bf4b-8566686f1577)]
interface nsIAccessibleCoordinateType : nsISupports

Constants

 The coordinates are relative to the screen.
const unsigned long COORDTYPE_SCREEN_RELATIVE = 0 
 The coordinates are relative to the window.
const unsigned long COORDTYPE_WINDOW_RELATIVE = 1 
 The coordinates are relative to the upper left corner of the bounding box
 of the immediate parent.
const unsigned long COORDTYPE_PARENT_RELATIVE = 2