typedef struct KEYS
	{
	BOOL	left_down ;	/* TRUE if key is depressed	*/
	BOOL	right_down ;	/* TRUE if key is depressed	*/
	BOOL	space_down ;	/* TRUE if key is depressed	*/
	} KEYS ;

/* ------------------------------------------------------------ */
/* Function prototypes						*/
/* ------------------------------------------------------------ */
BOOL Blocked(int row, int col, int rot) ;
BOOL HandleObject(KEYS *keys) ;
BOOL On(int rot, int row, int col) ;
void PaintObject(int row, int col, int rot, BOOL on, char clr) ;
void Tone(int hertz) ;
KEYS *GetKeys(void) ;

/* ------------------------------------------------------------ */
/* Macros for assembling ascii code & attribute codes		*/
/* ------------------------------------------------------------ */
#define	ATTB(fgd, bgd)	(((bgd) << 4) | (fgd))
#define	BLACK		0
#define	WHITE		7
#define	NORMAL		ATTB(WHITE, BLACK)
#define	CELL(ch, att)	(((att) << 8) | ch)

#define	EMPTY		CELL(' ', NORMAL)