EraseOval
Rect *theRect ; rectangle defining oval's position and size EraseOval fills an oval, positioned just inside of a rectangular, area with the background pattern of the current GrafPort. theRect is the address of an 8-byte Rect structure, in local coordinates.
Notes: EraseOval is functionally equivalent to: The pen position is not changed by this function.
As with all Quickdraw drawing, the output is clipped to the intersection of
the current GrafPort's bitMap boundary rectangle, the port rectangle, clipping region, and visible region.