space-invaders.py

# Modules
import pygame
import os
from pygame.locals import *
import random

# ---------- Application class
class Application():
    width = 640
    height = 640
    running = True
    total_score = 0
    kill_points = 10
    difficulty = 1

    def __init__(self, background, caption):
        self.background = background
        self.caption = caption
        Application.screen = pygame.display.set_mode((Application.width, Application.height))
        pygame.display.set_caption(caption)
        self.draw_background()
        self.score_cfg = pygame.font.SysFont('Helvetica', 20, True)

    def draw_background(self):
        Application.screen.blit(self.background, (0, 0))

    def create_element(self, image, pos_x, pos_y):
        Application.screen.blit(image, (pos_x, pos_y))

    def score_up(self):
        self.total_score += self.kill_points

    def show_score(self):
        self.score = self.score_cfg.render('Score: ' + str(self.total_score), True, (255, 230, 0))
        Application.screen.blit(self.score, (10, 10))

# ---------- Enemy class
class Spaceship():
    speed = 7

    def __init__(self, image, pos_x, pos_y):
        self.image = image
        self.pos_x = pos_x
        self.pos_y = pos_y
        self.draw()

    def draw(self):
        screen.create_element(self.image, self.pos_x, self.pos_y)

    def move(self, direction):
        self.verify_collision()
        if direction == 'left':
            self.pos_x -= Spaceship.speed
        elif direction == 'right':
            self.pos_x += Spaceship.speed
        self.draw()

    def shot(self):
        bullet = Bullet(self.pos_x + 15, self.pos_y)
        enemy_killed = False
        self.fire = True
        while self.fire:
            bullet.move('spaceship')
            screen.draw_background()
            self.draw()

            # Move left/right
            if key_pressed[K_LEFT]:
                spaceship.move('left')
            if key_pressed[K_RIGHT]:
                spaceship.move('right')

            for index, enemy in enumerate(enemies):
                enemy.auto_move()
                if bullet.pos_y <= enemy.pos_y + 64 and ((bullet.pos_x >= enemy.pos_x - 32) and ( bullet.pos_x <= enemy.pos_x + 32)):
                    enemies.pop(index)
                    enemy.kill()
                    bullet.pos_y = 0
                    enemy_killed = True
                    self.fire = False

            if not enemy_killed and self.fire:
                bullet.move('spaceship')

            screen.show_score()
            pygame.display.flip()

    def verify_collision(self):
        if self.pos_x >= Application.width - 64:
            self.pos_x = Application.width - 64
        elif self.pos_x <= 0:
            self.pos_x = 0

# ---------- Bullet class
class Bullet():
    speed = 7
    image_path = os.path.join('/home/lucas/python/space-invaders', 'bullet.png')
    image = pygame.image.load(image_path)

    def __init__(self, pos_x, pos_y):
        self.pos_x = pos_x
        self.pos_y = pos_y
        self.draw()

    def draw(self):
        screen.create_element(Bullet.image, self.pos_x, self.pos_y)

    def move(self, type):
        if type == 'enemy':
            self.pos_y += Bullet.speed
        elif type == 'spaceship':
            self.pos_y -= Bullet.speed
        self.draw()

# ---------- Enemy class
class Enemy():
    direction = 'right'
    speed = 1

    def __init__(self, image, pos_x, pos_y):
        self.image = image
        self.pos_x = pos_x
        self.pos_y = pos_y

    def create(self):
        screen.create_element(self.image, self.pos_x, self.pos_y)

    def auto_move(self):

        # Look for collisions
        self.verify_collision()

        # Move
        if Enemy.direction == 'right':
            self.pos_x += Enemy.speed
        elif Enemy.direction == 'left':
            self.pos_x -= Enemy.speed
        self.create()

    def shot(self):
        enemy_shot = random.choice(enemies)
        bullet = Bullet(enemy_shot.pos_x + 15, enemy_shot.pos_y)
        spaceship_killed = False
        while bullet.pos_y <= Application.height:
            screen.draw_background()
            spaceship.draw()

            for index, enemy in enumerate(enemies):
                enemy.auto_move()
                if bullet.pos_y <= spaceship.pos_y + 64 and ((bullet.pos_x >= spaceship.pos_x - 32) and ( bullet.pos_x <= spaceship.pos_x + 32)):
                    enemy.auto_move()
                    # spaceship_killed = True

            if not spaceship_killed:
                bullet.move('enemy')

            screen.show_score()
            pygame.display.flip()

    def kill(self):
        screen.score_up()

    def verify_collision(self):
        if self.pos_x >= Application.width - 64:
            self.pos_x = Application.width - 64
            Enemy.direction = 'left'
        elif self.pos_x <= 0:
            self.pos_x = 0
            Enemy.direction = 'right'

# Create application
pygame.init()
background_draw = os.path.join('/home/lucas/python/space-invaders', 'background.jpg')
background_image = pygame.image.load(background_draw)
screen = Application(background_image, 'Space Invaders')

# Create spaceship
spaceship_draw = os.path.join('/home/lucas/python/space-invaders', 'spaceship.png')
spaceship_image = pygame.image.load(spaceship_draw)
spaceship = Spaceship(spaceship_image, 325, 570)

# Create enemies
enemies = []
enemy_draw = os.path.join('/home/lucas/python/space-invaders', 'enemy.png')
enemy_image = pygame.image.load(enemy_draw)
for x in range(96, 576, 96):
    for y in range(32, 252, 64):
        enemy = Enemy(enemy_image, x, y)
        enemies.append(enemy)
        enemy.create()


# Define enemy shot delay
if Application.difficulty == 1:
    enemy_shot_delay = 3 * 60
    enemy_shot_delay_temp = 0

# -------- MAIN LOOP
while Application.running:

    # Draw background and score
    screen.draw_background()
    screen.show_score()

    # Spaceship
    spaceship.draw()

    # Enemies automatic move
    for enemy in enemies:
        enemy.auto_move()

    # if enemy_shot_delay_temp == enemy_shot_delay:
    #     enemy.shot()
    #     enemy_shot_delay_temp = 0


    # Get pressed keys
    key_pressed = pygame.key.get_pressed()
    pygame.key.set_repeat(300, 0)

    # Move left/right
    if key_pressed[K_LEFT]:
        spaceship.move('left')
    if key_pressed[K_RIGHT]:
        spaceship.move('right')

    # Shot
    if key_pressed[K_SPACE]:
        spaceship.shot()

    # Update screen
    pygame.display.flip()

    # Exit game
    for event in pygame.event.get():

        # Close app
        if event.type == pygame.QUIT or (event.type == KEYDOWN and event.key == K_ESCAPE):
            Application.running = False

    enemy_shot_delay_temp += 1