typedef void (* FGCBJoystick )( unsigned int, int, int, int );
typedef void (* FGCBOverlayDisplay)( void );
typedef void (* FGCBSpaceMotion )( int, int, int );
typedef void (* FGCBJoystick )( unsigned int, int, int, int );
typedef void (* FGCBOverlayDisplay)( void );
typedef void (* FGCBSpaceMotion )( int, int, int );