added async stone detection thread

field.py

@@ -13,6 +13,7 @@ class Field():
         else:
             self.state = [[' ' for cols in range(Field.WIDTH)]
                           for rows in range(Field.HEIGHT)]
+        self.cleared_rows = 0
 
     def __str__(self):
         BAR = '   ' + '-' * (Field.WIDTH * 2 + 1) + '\n    ' + \
@@ -21,6 +22,13 @@ class Field():
             '{:2d} |'.format(i) + ' '.join(row) + '|'
                 for i, row in enumerate(self.state)]) + '\n' + BAR
 
+
+    def rotate_state(self):
+        self.state = list(zip(*self.state[::-1]))
+
+    def get_line_count(self):
+        return self.cleared_rows
+
     def _test_tetromino(self, tetromino, row, column):
         """
         Tests to see if a tetromino can be placed at the specified row and
@@ -80,6 +88,7 @@ class Field():
         self.state = list(filter(lambda row: row.count(' ') != 0, self.state))
         while len(self.state) < Field.HEIGHT:
             self.state.insert(0, [' ' for col in range(Field.WIDTH)])
+            self.cleared_rows = self.cleared_rows + 1
 
     def copy(self):
         """