Draws a Circle in an Area
Source position: agraphics.pas line 2303
| function AreaCircle( | 
| Rp: PRastPort; | 
| xCenter: SmallInt; | 
| yCenter: SmallInt; | 
| r: SmallInt | 
| ):LongWord; | 
| Rp | 
 | A pointer to a RastPort | 
| xCenter | 
 | X coordinate for center of Circle | 
| yCenter | 
 | Y coordinate for center of Circle | 
| r | 
 | Radius of Circle | 
Calls AreaEllipse() with a = b = r