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--- bullet_game [2024/08/31 01:35] – created appledog
+++ bullet_game [2024/09/11 06:43] (current) – created appledog
@@ Line 2: / Line 2: @@
 Bullet Game is our near-end stage pygame 2d game framework example. We've already done at least 6 or 7 other games using pygame. So this will document the patterns we have learned.
-== Screen and Window
+We began by "just writing" a game, then the second part was refactoring the game. I wanted to make refactoring it's own project. What are the goals of this refactoring?
-The first thing we always do is have a Screen class and a Window class. The Screen class defines things like WIDTH and HEIGHT, and the Window class holds the pygame screen and other pygame initialization.
-Initially, this code would appear at the start of a main.py. Later we moved it into class Game's __init__. However, to keep things clean we made it into it's own class.
+* Refactoring
+** Encapsulation
+** Light Commentary (code commentary) ex. IN and OUT for functions.
-=== class Screen:
+The primary goal is encapsulation. So, we're going to break up the old main into several new classes.
+== PyGame Framework
+The first part of this is the use of [[pygame framework]]. We'll describe the additions here.
+=== Also See
+* [[Box Sprites]] -- the kind of sprites first used in this game.
+== Bullet Game
+Here is the code we added, starting with main.py:
+=== main.py
 <Code:Python>
+from Window import *
+from Game import *
+def main():
+    window = Window()
+    window.setCaption("Bullet Game")
+    window.setSize(Screen.WIDTH, Screen.HEIGHT)
+    window.setFont("assets/ps2p.ttf", 32)
+    game = Game(window)
+    game.start()
+if __name__ == "__main__":
+    main()
 </Code>
-=== class Window:
+=== Screen,py
-==== def __init__
+<Code:Python>
-This calls pygame.init(). See [[main]]
+class Screen:
+    WIDTH = 800
+    HEIGHT = 600
+    FPS = 60
-==== full code
+    MARGIN = 96
+    GAMETOP = MARGIN
+    GAMEBOT = HEIGHT - MARGIN
+</Code>
+=== Game.py
 <Code:Python>
 import pygame
+import random
+import pickle
-class Window:
+from Screen import *
-    def __init__(self):
+from Window import *
-        pygame.init()
+from Bullet import *
+from Color import *
+from Screen import *
+from Zombie import *
+from SpaceShip import *
+from Sound import *
+from Player import *
+from Constants import *
+from Level import *
+from Star import *
-    def setLogo(self, filename):
-        self.logo = pygame.image.load(filename)
-        pygame.display.set_icon(self.logo)
-        return self.logo
-    def setCaption(self, cap):
+class Game:
-        pygame.display.set_caption(cap)
+    def __init__(self, window):
+        self.window = window
+        self.sound = Sound()
-    def setSize(self, width, height):
+        # Initialize Game World Data
+        # The Player & Level
+        self.player = Player()
+        self.player.hiscore = self.load_hiscore("score.txt")
+        self.level = Level(1, self.player)
+        # Bullet list
+        self.bullets = pygame.sprite.Group()
+        # Zombies list
+        self.zombies = pygame.sprite.Group()
+        self.spaceships = pygame.sprite.Group()
+        # 30 random stars.
+        self.stars = []
+        for n in range(30):
+            x = random.randint(0, Screen.WIDTH)
+            y = random.randint(0, Screen.HEIGHT)
+            self.stars.append((x, y))
+        # All member variables are now globals:
+        # Try commenting it out to see what happens!
+        globals().update(self.__dict__)
+    #################################
+    ##          Main Loop          ##
+    #################################
+    def start(self):
+        # Clock for controlling the frame rate
+        clock = pygame.time.Clock()
+        # Main game loop
+        running = True
+        frame_counter = 0
+        ##################
+        # GAME LOOP ORDER OF EVENTS:
+        ##################
+        sound.play("start")
+        # pygame.mixer.init()
+        # pygame.mixer.music.load('assets/sound/waveafterwave.mp3')
+        # pygame.mixer.music.play()
+        # Start of Game Loop
+        time_start = time.time() * 1000
+        LEVEL_DELAY = 3000
+        while running:
+            time_clock = (time.time() * 1000) - time_start
+            frame_counter += 1
+            if frame_counter > 60:
+                frame_counter = 1
+            ########################
+            # 1. EVENT HANDLING
+            ########################
+            for event in pygame.event.get():
+                if event.type == pygame.QUIT:
+                    running = False
+                    quit_game()
+                if event.type == pygame.KEYDOWN:
+                    if event.key == pygame.K_z:
+                        self.create_spaceship()
+                    if event.key == pygame.K_ESCAPE:
+                        self.quit_game()
+                    if event.key == pygame.K_q:
+                        self.quit_game()
+                    if event.key == pygame.K_w:
+                        x = self.player.rect.x + self.player.SIZE / 2
+                        y = self.player.rect.y + self.player.SIZE / 2
+                        self.create_bullet(x, y, 0, -1)
+            # Continuous (frame-by-frame) Key press handling
+            keys = pygame.key.get_pressed()
+            if keys[pygame.K_LEFT]:
+                self.player.rect.x -= self.player.SPEED
+            if keys[pygame.K_RIGHT]:
+                self.player.rect.x += self.player.SPEED
+            #######################
+            # 2. RULES SECTION
+            #######################
+            ### Level-specifc stuff:
+            if time_clock > LEVEL_DELAY:
+                commands = self.level.tick_hook()
+                for cmd in commands:
+                    if cmd == "create zombie":
+                        self.create_zombie()
+                    if cmd == "create spaceship":
+                        self.create_spaceship()
+                    if cmd == "go to level2":
+                        self.kill_enemies()
+                        time_start = time.time() * 1000
+                        self.level = Level(2, player)
+                    if cmd == "go to level3":
+                        self.kill_enemies()
+                        time_start = time.time() * 1000
+                        self.level = Level(3, self.player)
+                    if cmd == "go to level4":
+                        self.kill_enemies()
+                        time_start = time.time() * 1000
+                        self.level = Level(4, self.player)
+            # 2b. rules for bullets
+            # 2b.1. Update the bullets position.
+            self.bullets.update()
+            # Update all stars.
+            for i in range(len(self.stars)):
+                (x, y) = self.stars[i]
+                y = y + 1
+                if y > Screen.HEIGHT:
+                    x = random.randint(0, Screen.WIDTH)
+                    y = 0
+                self.stars[i] = (x, y)
+            if time_clock > LEVEL_DELAY:
+                # 2a rules for the square
+                # Keep the square within bounds
+                self.player.update()
+                # 2c. rules for zombies
+                # 2c.1. Update the zombies position.
+                self.zombies.update()
+                self.spaceships.update()
+            # Clear the screen
+            self.window.screen.fill(Color.BLACK)
+            # Draw stars first (because its a background)
+            for s in self.stars:
+                pygame.draw.rect(self.window.screen, "white", pygame.Rect(s[0], s[1], 2, 2))
+            # Draw the square
+            # pygame.draw.rect(screen, square_color, (square_x, square_y, square_size, square_size))
+            self.window.screen.blit(self.player.image, self.player.rect)
+            if time_clock > LEVEL_DELAY:
+                # Draw the zombies.
+                self.zombies.draw(self.window.screen)
+                self.spaceships.draw(self.window.screen)
+                # ships make a sound, if...
+                if self.spaceships:
+                    if frame_counter == 30:
+                        self.sound.play("pellet")
+            # Draw the bullets.
+            self.bullets.draw(self.window.screen)
+            # write score.
+            if frame_counter < 30:
+                s = "1UP"
+                text_surface = self.window.font.render(s, True, "white")
+                self.window.screen.blit(text_surface, (96, 10))
+            s = f"{self.player.score:02}"
+            text_surface = self.window.font.render(s, True, "red")
+            self.window.screen.blit(text_surface, (160, 42))
+            # do high score.
+            s = "HIGH SCORE"
+            text_surface = self.window.font.render(s, True, "white")
+            self.window.screen.blit(text_surface, (320, 10))
+            s = f"{self.player.hiscore:02}"
+            text_surface = self.window.font.render(s, True, "red")
+            self.window.screen.blit(text_surface, (512, 42))
+            s = f"{self.level.level_number}"
+            text_surface = self.window.font.render(s, True, "red")
+            self.window.screen.blit(text_surface, (700, 42))
+            if time_clock < LEVEL_DELAY:
+                s = f"Level {self.level.level_number}"
+                text_surface = self.window.font.render(s, True, "white")
+                tr = text_surface.get_rect()
+                tr.center = (Screen.WIDTH // 2, Screen.HEIGHT // 2 - 100)
+                self.window.screen.blit(text_surface, tr)
+            # Update the display
+            pygame.display.flip()
+            if time_clock > LEVEL_DELAY:
+                # 3. INTERSPRITE COLLISION
+                # 3a. bullets kill zombies
+                collisions = pygame.sprite.groupcollide(self.bullets, self.zombies, True, True)
+                collisions2 = pygame.sprite.groupcollide(self.bullets, self.spaceships, True, True)
+                if collisions:
+                    self.player.score = self.player.score + len(collisions)
+                    if self.player.score > self.player.hiscore:
+                        self.player.hiscore = self.player.score
+                if collisions or collisions2:
+                    n = random.randint(1, 2)
+                    if n == 1:
+                        self.sound.play("boom")
+                    else:
+                        self.sound.play("boom7")
+                if collisions2:
+                    self.player.score = self.player.score + (len(collisions2) * 10)
+                    if self.player.score > self.player.hiscore:
+                        self.player.hiscore = self.player.score
+                # Players may not touch zombies:
+                collided_enemies = pygame.sprite.spritecollide(self.player, self.zombies, False)
+                if collided_enemies:
+                    print("You are DEAD!")
+                    print(" High score: " + str(self.player.hiscore))
+                    print(" Your score: " + str(self.player.score))
+                    self.quit_game()
+            # Control the frame rate
+            clock.tick(60)
+    #################################
+    ##      Support Functions      ##
+    #################################
+    def create_bullet(self, x, y, dx, dy):
+        self.bullet = Bullet(x, y, dx, dy)
+        self.bullets.add(self.bullet)
+        self.sound.play("laser")
+        if Constants.VERBOSE:
+            print("bullet created")
+    def create_zombie(self):
+        sx = random.randint(50, Screen.WIDTH - 50)
+        sy = 0 + Screen.MARGIN
+        dx = 0
+        dy = 1
+        z = Zombie(sx, sy, dx, dy)
+        self.zombies.add(z)
+        if Constants.VERBOSE:
+            print("zombie created")
+    def create_spaceship(self):
+        sx = Screen.WIDTH
+        sy = 0 + Screen.MARGIN
+        dx = -1
+        dy = 0
+        if random.randint(1, 2) == 1:
+            dx = 1
+            sx = 0
+        s = SpaceShip(sx, sy, dx, dy)
+        self.spaceships.add(s)
+        if Constants.VERBOSE:
+            print("spaceship created")
+    def kill_enemies(self):
+        for z in self.zombies:
+            z.kill()
+        for s in self.spaceships:
+            s.kill()
+    # Save the score to a text file.
+    def save_hiscore(self, filename, score):
+        with open(filename, 'w') as file:
+            file.write(str(score))
+    # Load the score from a text file.
+    def load_hiscore(self, filename):
+        try:
+            with open(filename, 'r') as file:
+                score = int(file.read())
+                return score
+        except:
+            print(f"Error. Resetting high score to 0.")
+            return 0
+    def quit_game():
+        self.save_hiscore("score.txt", str(self.player.hiscore))
+        pygame.quit()
+        quit()
+</Code>
+=== Level.py
+<Code:Python>
+import random
+class Level:
+    def __init__(self, n, p):
+        self.level_number = n
+        self.player = p
+        match self.level_number:
+            case 1:
+                self.tick_hook = self.level1
+            case 2:
+                self.tick_hook = self.level2
+            case 3:
+                self.tick_hook = self.level3
+            case 4:
+                self.tick_hook = self.level4
+            case default:
+                print("Unknown Level Number: " + str(n))
+                print("Defaulting to Level 1!")
+                self.tick_hook = self.level1
+        return
+##### Tick Hooks
+    def level1(self):
+        commands = []
+        if random.randint(1,45) == 1:
+            commands.append("create zombie")
+        if self.player.score >= 20:
+            commands.append("go to level2")
+        return commands
+    def level2(self):
+        commands = []
+        if random.randint(1, 35) == 1:
+            commands.append("create zombie")
+        if self.player.score >= 40:
+            commands.append("go to level3")
+        return commands
+    def level3(self):
+        commands = []
+        if random.randint(1, 30) == 1:
+            commands.append("create zombie")
+        if random.randint(1, 500) == 1:
+            commands.append("create spaceship")
+        if self.player.score >= 80:
+            commands.append("go to level4")
+        return commands
+    def level4(self):
+        commands = []
+        if random.randint(1, 20) == 1:
+            commands.append("create zombie")
+        if random.randint(1, 350) == 1:
+            commands.append("create spaceship")
+        #if self.player.score > 320:
+        #    commands.append("go to level5")
+        return commands
+</Code>
+=== Object.py
+<Code:Python>
+import pygame
+class Object(pygame.sprite.Sprite):
+    def __init__(self, x, y, width, height, name=None):
+        super().__init__()
+        self.rect = pygame.Rect(x, y, width, height)
+        self.image = pygame.Surface((width, height), pygame.SRCALPHA)
         self.width = width
         self.height = height
-        self.size = (width, height)
+        self.name = name
-        self.screen = pygame.display.set_mode(self.size)
-        return self.screen
-    def setFont(self, filename, size):
+    def draw(self, win, offset_x, offset_y):
-        pygame.font.init()
+        win.blit(self.image, (self.rect.x - offset_x, self.rect.y + offset_y))
-        self.font = pygame.font.Font(filename, size)
-        font_width, font_height = self.font.size("@")
+</Code>
-        self.fontwidth = font_width
-        self.fontheight = size
-        return self.font</Code>
+=== Player.py
+<Code:Python>
+import pygame
+import time
+from Color import *
+from Screen import *
+# Define the Bullet Sprite class
+class Player(pygame.sprite.Sprite):
+    SPEED = 5
+    SIZE = 20
+    COLOR = Color.WHITE
+    def __init__(self):
+        super().__init__()
+        self.ticks = 0
+        self.loops = 0
+        # Create a surface for the bullet
+        self.image = pygame.Surface((self.SIZE, self.SIZE))
+        # Fill the surface with a color
+        self.image.fill(self.COLOR)
+        # Get the rectangle for positioning
+        self.rect = self.image.get_rect()
+        # Set the initial position
+        self.rect.center = (Screen.WIDTH//2, Screen.HEIGHT-50)
+        self.score = 0
+        self.hiscore = 0
+    def update(self):
+        # Restrict to screen.
+        if self.rect.x < 0:
+            self.rect.x = 0
+        if self.rect.x > Screen.WIDTH - self.SIZE:
+            self.rect.x = Screen.WIDTH - self.SIZE
+        if self.rect.y < 0:
+            self.rect.y = 0
+        if self.rect.y > Screen.HEIGHT - self.SIZE:
+            self.rect.y = Screen.HEIGHT - self.SIZE
+        # Easier to read, but, slower.
+        #self.rect.x = max(0, min(self.rect.x, Screen.WIDTH - self.SIZE))
+        #self.rect.y = max(0, min(self.rect.y, Screen.HEIGHT - self.SIZE))
+</Code>
+=== Sound.py
+<Code:Python>
+import pygame as a
+class Sound:
+    def __init__(self):
+        a.mixer.init()
+        dir = 'assets/sound/'
+        self.sounds = {}
+        self.sounds["laser"] = a.mixer.Sound(dir+'laser1.wav')
+        self.sounds["laser"].set_volume(0.15)
+        self.sounds["boom"] = a.mixer.Sound(dir+'boom6.wav')
+        self.sounds["boom7"] = a.mixer.Sound(dir+'boom7.wav')
+        self.sounds["start"] = a.mixer.Sound(dir+'start4.wav')
+        self.sounds["pellet"] = a.mixer.Sound(dir+'pellet.wav')
+    def play(self, sound):
+        if sound in self.sounds:
+            self.sounds[sound].play()
+        else:
+            print(f"There is no {sound} sound!")
+</Code>