Enhance Coin-Poison game: add levels, lives, shield, and dynamic score

- Introduced levels: game speed and difficulty increase after clearing coins
- Added 3-life system before game over
- Added shield power-up that protects from poison collision
- Display updated score, coins left, lives, and level dynamically
- Refactored spawn and reset logic for better code structure
- Significant gameplay improvements to make game more engaging and robust

Author: Achi-Vyshnavi

Coin-Poison/coin-poison.py

@@ -1,40 +1,51 @@
 import pygame
 import random
+
 pygame.init()
 
+# ================== CONFIG ==================
 GRID_SIZE = 40
-GRID_WIDTH = 17  
-GRID_HEIGHT = 17  
+GRID_WIDTH = 17
+GRID_HEIGHT = 17
 SCREEN_WIDTH = GRID_SIZE * GRID_WIDTH
 SCREEN_HEIGHT = GRID_SIZE * GRID_HEIGHT
-BG_COLOR = (30, 30, 30)  
+
+BG_COLOR = (30, 30, 30)
 PLAYER_COLOR = (0, 255, 0)
 COIN_COLOR = (255, 215, 0)
 POISON_COLOR = (255, 0, 0)
+SHIELD_COLOR = (0, 191, 255)
+
 FPS = 15
 
 screen = pygame.display.set_mode((SCREEN_WIDTH, SCREEN_HEIGHT))
-pygame.display.set_caption("coin&poison")
+pygame.display.set_caption("Coin & Poison Adventure")
 
 font = pygame.font.Font(None, 36)
 
+# ================== CLASSES ==================
+
 class Player(pygame.sprite.Sprite):
+    """Player controlled by arrow keys"""
     def __init__(self):
         super().__init__()
         self.image = pygame.Surface((GRID_SIZE, GRID_SIZE))
         self.image.fill(PLAYER_COLOR)
         self.rect = self.image.get_rect()
         self.rect.topleft = (0, 0)
         self.score = 0
+        self.lives = 3
+        self.shield = False
 
     def move(self, dx, dy):
         new_rect = self.rect.move(dx * GRID_SIZE, dy * GRID_SIZE)
-        if 0 <= new_rect.left < SCREEN_WIDTH and 0 <= new_rect.top < SCREEN_HEIGHT: # within limits
+        if 0 <= new_rect.left < SCREEN_WIDTH and 0 <= new_rect.top < SCREEN_HEIGHT:
             self.rect = new_rect
         else:
-            self.score -= 1 # hit the boundary
+            self.score -= 1  # penalize hitting boundary
 
 class Coin(pygame.sprite.Sprite):
+    """Collectible coin"""
     def __init__(self, x, y):
         super().__init__()
         self.image = pygame.Surface((GRID_SIZE, GRID_SIZE))
@@ -43,15 +54,27 @@ def __init__(self, x, y):
         self.rect.topleft = (x * GRID_SIZE, y * GRID_SIZE)
 
 class Poison(pygame.sprite.Sprite):
+    """Poison block that reduces life"""
     def __init__(self, x, y):
         super().__init__()
         self.image = pygame.Surface((GRID_SIZE, GRID_SIZE))
         self.image.fill(POISON_COLOR)
         self.rect = self.image.get_rect()
         self.rect.topleft = (x * GRID_SIZE, y * GRID_SIZE)
 
-# to spawn coin and poison blocks without overlapping with each other and player
+class Shield(pygame.sprite.Sprite):
+    """Power-up shield to protect from poison"""
+    def __init__(self, x, y):
+        super().__init__()
+        self.image = pygame.Surface((GRID_SIZE, GRID_SIZE))
+        self.image.fill(SHIELD_COLOR)
+        self.rect = self.image.get_rect()
+        self.rect.topleft = (x * GRID_SIZE, y * GRID_SIZE)
+
+# ================== HELPER FUNCTIONS ==================
+
 def spawn_objects(num_objects, avoid_positions):
+    """Spawn objects without overlapping"""
     objects = []
     while len(objects) < num_objects:
         x = random.randint(0, GRID_WIDTH - 1)
@@ -61,35 +84,67 @@ def spawn_objects(num_objects, avoid_positions):
             avoid_positions.add((x, y))
     return objects
 
+def reset_level():
+    """Reset coins, poisons, and optionally add shield"""
+    global coins, poisons, shield_powerups, all_sprites, avoid_positions, FPS, level
+    level += 1
+    FPS += 1  # increase speed for next level
+    num_coins = 10 + level * 2
+    num_poisons = 5 + level
+
+    # Clear old objects
+    for sprite in coins.sprites() + poisons.sprites() + shield_powerups.sprites():
+        all_sprites.remove(sprite)
+    
+    # Reset positions
+    avoid_positions = {(player.rect.x // GRID_SIZE, player.rect.y // GRID_SIZE)}
+    
+    # Spawn coins
+    coin_positions = spawn_objects(num_coins, avoid_positions)
+    coins = pygame.sprite.Group()
+    for pos in coin_positions:
+        coin = Coin(*pos)
+        coins.add(coin)
+        all_sprites.add(coin)
+
+    # Spawn poisons
+    poison_positions = spawn_objects(num_poisons, avoid_positions)
+    poisons = pygame.sprite.Group()
+    for pos in poison_positions:
+        poison = Poison(*pos)
+        poisons.add(poison)
+        all_sprites.add(poison)
+
+    # Spawn shield occasionally
+    shield_positions = spawn_objects(1, avoid_positions)
+    shield_powerups = pygame.sprite.Group()
+    for pos in shield_positions:
+        shield = Shield(*pos)
+        shield_powerups.add(shield)
+        all_sprites.add(shield)
+
+# ================== GAME INIT ==================
+
 player = Player()
 all_sprites = pygame.sprite.Group()
 all_sprites.add(player)
 
-# total no of coins and poison blocks
-num_coins = 20  
-num_poisons = 10  
-
+coins = pygame.sprite.Group()
+poisons = pygame.sprite.Group()
+shield_powerups = pygame.sprite.Group()
 avoid_positions = {(player.rect.x // GRID_SIZE, player.rect.y // GRID_SIZE)}
 
-poison_positions = spawn_objects(num_poisons, avoid_positions)
-poisons = pygame.sprite.Group()
-for pos in poison_positions:
-    poison = Poison(*pos)
-    poisons.add(poison)
-    all_sprites.add(poison)
-
-coin_positions = spawn_objects(num_coins, avoid_positions)
-coins = pygame.sprite.Group()
-for pos in coin_positions:
-    coin = Coin(*pos)
-    coins.add(coin)
-    all_sprites.add(coin)
+level = 1
+reset_level()
 
 clock = pygame.time.Clock()
-
 running = True
+
+# ================== GAME LOOP ==================
+
 while running:
-    clock.tick(FPS)  
+    clock.tick(FPS)
+
     for event in pygame.event.get():
         if event.type == pygame.QUIT:
             running = False
@@ -104,24 +159,39 @@ def spawn_objects(num_objects, avoid_positions):
     if keys[pygame.K_DOWN]:
         player.move(0, 1)
 
+    # Collect coins
     collected_coins = pygame.sprite.spritecollide(player, coins, True)
     player.score += len(collected_coins)
 
-    if pygame.sprite.spritecollideany(player, poisons):
-        print(f"collided with poison block! score: {player.score}")
-        running = False
+    # Collect shield
+    if pygame.sprite.spritecollide(player, shield_powerups, True):
+        player.shield = True
+        print("Shield activated! Next poison hit will be ignored.")
 
-    # if all coins collected, won
+    # Poison collision
+    if pygame.sprite.spritecollideany(player, poisons):
+        if player.shield:
+            player.shield = False
+            print("Shield protected you from poison!")
+        else:
+            player.lives -= 1
+            if player.lives == 0:
+                print(f"Game Over! Final Score: {player.score}")
+                running = False
+            else:
+                print(f"Hit poison! Lives left: {player.lives}")
+
+    # Level completed
     if len(coins) == 0:
-        print(f"collected all coins! score: {player.score}")
-        running = False
+        print(f"Level {level} cleared! Moving to next level...")
+        reset_level()
 
+    # Draw everything
     screen.fill(BG_COLOR)
     all_sprites.draw(screen)
-
-    score_text = font.render(f"score: {player.score}", True, (255, 255, 255))
-    screen.blit(score_text, (10, 10)) 
+    score_text = font.render(f"Score: {player.score} | Coins left: {len(coins)} | Lives: {player.lives} | Level: {level}", True, (255, 255, 255))
+    screen.blit(score_text, (10, 10))
 
     pygame.display.flip()
 
-pygame.quit()
+pygame.quit()