Implemented hovering stones under mouse cursor, and implemented a simple game clock

pygo.py

@@ -8,7 +8,7 @@ import pygame
 from pygame.locals import *
 
 
-def load_png(name):
+def load_png(name, alpha=None):
     """ Load image and return image object"""
     fullname = os.path.join('res', name)
 
@@ -19,6 +19,9 @@ def load_png(name):
         else:
             image = image.convert_alpha()
 
+        if alpha is not None:
+            image.set_alpha(alpha)
+
     except pygame.error, message:
         print 'Cannot load image:', fullname
         raise SystemExit, message
@@ -34,10 +37,12 @@ def build_img_res():
     ret['w'] = load_png('go_w.png')
     ret['wT'] = load_png('go_w.png')
     ret['wT'].blit(triangle, (0,0))
+    ret['wH'] = load_png('go_w.png', 128)
 
     ret['b'] = load_png('go_b.png')
     ret['bT'] = load_png('go_b.png')
     ret['bT'].blit(triangle, (0,0))
+    ret['bH'] = load_png('go_b.png', 128)
 
     circle = load_png('go_c.png')
 
@@ -122,8 +127,23 @@ class Goban:
         self.captures = []
         self.captures.append(0)
         self.captures.append(0)
+        self.hover = None
+        self.elapsed_time = 0
 
 
+    def set_hover(self, pos):
+        if not self._valid_move(pos):
+            self.clear_hover()
+            return
+
+        x,y = pos
+        self.hover = self.board[x][y]
+
+    
+    def clear_hover(self):
+        self.hover = None
+        
+
     def place_stone(self, pos):
         if not self._valid_move(pos):
             return
@@ -176,7 +196,11 @@ class Goban:
 
         kills_group = False
         for d in [(x, y+1), (x, y-1), (x+1, y), (x-1, y)]:
-            if not self._has_liberties(d, opponent):
+            new_x, new_y = d
+            if new_x < 0 or new_x > 18 or new_y < 0 or new_y > 18:
+                continue
+            
+            if self._has_liberties(d, opponent) == 0:
                 kills_group = True
                 break
             self._clear_checks()
@@ -274,12 +298,21 @@ class Goban:
         for row in self.board:
             j = 0
             for square in row:
-                s = pygame.transform.scale(img_res[square.get_draw_code()], (inc, inc))
+                s = img_res[square.get_draw_code()]
+                s = pygame.transform.scale(s, (inc, inc))
                 ret.blit(s, (j*inc,i*inc))
+
+                if self.hover == square:
+                    c = img_res['bH']
+                    if self.turn == 1:
+                        c = img_res['wH']
+                    c = pygame.transform.scale(c, (inc, inc))
+                    ret.blit(c, (j*inc,i*inc))
+
                 j += 1
             i += 1
 
-        return ret.convert()
+        return ret.convert_alpha()
 
 
     def draw_info(self):
@@ -288,6 +321,7 @@ class Goban:
         textbox.fill((250, 250, 250))
 
         font = pygame.font.Font(None, 24)
+        time = font.render('Time: {:02d}:{:02d}'.format(self.elapsed_time / 60, self.elapsed_time % 60), 1, (10, 10, 10))
         heading = font.render('Captures', 1, (10, 10, 10))
         black_cap = font.render('Black: {}'.format(self.captures[0]), 1, (10, 10, 10))
         white_cap = font.render('White: {}'.format(self.captures[1]), 1, (10, 10, 10))
@@ -297,6 +331,7 @@ class Goban:
         textbox.blit(black_cap, (0, 28))
         textbox.blit(white_cap, (0, 56))
         textbox.blit(turn, (0, 100))
+        textbox.blit(time, (0, 150))
 
         return textbox
 
@@ -330,11 +365,27 @@ def main():
     screen.blit(background, (0, 0))
     pygame.display.flip()
 
+    pygame.time.set_timer(USEREVENT, 1000)
+
     while True:
         event = pygame.event.wait()
         
         if event.type == QUIT:
             return
+
+        # Hover a transparent stone over our
+        # cursor position, assuming play is legal
+        if event.type == MOUSEMOTION:
+            x, y = event.pos
+            row = y / board_inc
+            col = x / board_inc
+
+            if x <= board_size:
+                goban.set_hover((row,col))
+            else:
+                goban.clear_hover()
+
+        # Place a stone on left-click
         if event.type == MOUSEBUTTONDOWN:
             x, y = event.pos
             row = y / board_inc
@@ -343,8 +394,12 @@ def main():
             if x <= board_size:
                 if event.button == 1:
                     goban.place_stone((row, col))
+                    
                 if event.button == 3:
                     goban.toggle_marked((row, col))
+
+        if event.type == USEREVENT:
+            goban.elapsed_time += 1
                 
         board = goban.draw_board(board_size, img_res)
         background.blit(board, (0,0))