(* These procedures are for use with 'TIGERSNAP' to be run on the TERAK. *)

PROCEDURE DRAWLINE(VAR RANGE:INTEGER; VAR S:PICFORMAT;
                   ROW, X0, Y0, DX, DY, PEN:INTEGER);
EXTERNAL;
  
PROCEDURE FRAME;
VAR I:INTEGER;
BEGIN
  FILLCHAR(SCREEN.C[0],9600,NUL);               (* CLEARS THE ARRAY AND   *)
  UNITWRITE(3,SCREEN.C[0],56);                  (* DRAWS A TERAK SCREEN   *)
  DRAWLINE(I,SCREEN,20,0,0,319,0,1);            (* SIZED FRAME            *)
  DRAWLINE(I,SCREEN,20,319,0,0,239,1);
  DRAWLINE(I,SCREEN,20,319,239,-319,0,1);
  DRAWLINE(I,SCREEN,20,0,239,0,-239,1);
  UNITWRITE(3,SCREEN.C[0],7);
END;
    
PROCEDURE SAVEPIC;                              (* A NUL PROCEDURE BECAUSE *)
BEGIN                                           (* THE FRAME IS DRAWN      *)
  MESSAGE := 'PIC SAVED';                       (* DIRECTLY INTO THE ARRAY *)
END;

PROCEDURE DRAWPIC;                              (* DRAWS WHAT IS IN THE    *)
BEGIN                                           (* ARRAY ON THE SCREEN     *)
  WRITE('Press any key :');
  READ(KEYBOARD,CH);
  UNITWRITE(3,SCREEN.C[0],56);
  READ(KEYBOARD,CH);
  UNITWRITE(3,SCREEN.C[0],7);
  MESSAGE := '';
END; (* DRAW PIC *)