class AlienInvasion:
"""Overall class to manage game assets and behavior"""
def __init__(self):
"""Initialize the game, and create game resources."""
pygame.init()
self.settings = Settings()
self.screen = pygame.display.set_mode((0, 0), pygame.FULLSCREEN)
self.settings.screen_width = self.screen.get_rect().width
self.settings.screen_height = self.screen.get_rect().height
pygame.display.set_caption("Alien Invasion")
# Create an instance to store game statistics and a scoreboard
self.stats = GameStats(self)
self.sb = Scoreboard(self)
self.ship = Ship(self)
self.bullets = pygame.sprite.Group()
self.aliens = pygame.sprite.Group()
self.sound_effects = SoundEffects()
self._create_fleet()
# Make the play buttons -- TO REFACTOR.
self.play_button = Button(self, (0, 255, 0), 200, 50)
self.hard_button = Button(self, (0, 0, 255), 100, 50)
self.crazy_button = Button(self, (255, 0, 0), 100, 50)
def run_game(self):
"""Start the main loop for the game"""
while True:
# Watch for keyboard and mouse events.
self._check_events()
if self.stats.game_active:
self.ship.update()
self._update_bullets()
self._update_aliens()
self._update_screen()
def _check_events(self):
"""Respond to keypresses and mouse events"""
for event in pygame.event.get():
if event.type == pygame.QUIT:
sys.exit()
elif event.type == pygame.KEYDOWN:
self._check_keydown_events(event)
elif event.type == pygame.KEYUP:
self._check_keyup_events(event)
elif event.type == pygame.MOUSEBUTTONDOWN:
mouse_pos = pygame.mouse.get_pos()
self._check_play_button(mouse_pos)
self._check_hard_button(mouse_pos)
self._check_crazy_button(mouse_pos)
def _check_play_button(self, mouse_pos):
"""Start a new game when the player clicks play."""
button_clicked = self.play_button.rect.collidepoint(mouse_pos)
if button_clicked and not self.stats.game_active:
# Reset game statistics
self._start_game()
def _check_hard_button(self, mouse_pos):
button_clicked = self.hard_button.rect.collidepoint(mouse_pos)
if button_clicked and not self.stats.game_active:
self.settings.difficulty_level = 'hard'
def _check_crazy_button(self, mouse_pos):
button_clicked = self.crazy_button.rect.collidepoint(mouse_pos)
if button_clicked and not self.stats.game_active:
self.settings.difficulty_level = 'crazy'
def _start_game(self):
# reset game stats
self.stats.reset_stats()
self.sb.prep_images()
# get rid of aliens and bullets
self.aliens.empty()
self.bullets.empty()
# create new fleet and re-center ship
self._create_fleet()
self.ship.center_ship()
# Hide the mouse cursor
pygame.mouse.set_visible(False)
self.settings.set_speedup_scale()
def _check_keydown_events(self, event):
"""respond to key presses"""
if event.key == pygame.K_RIGHT:
# Move the ship to right
self.ship.moving_right = True
elif event.key == pygame.K_LEFT:
# Move the ship to the left
self.ship.moving_left = True
elif event.key == pygame.K_SPACE:
self._fire_bullet()
elif event.key == pygame.K_p and not self.stats.game_active:
self._start_game()
elif event.key == pygame.K_q:
sys.exit()
def _check_keyup_events(self, event):
"""Respond to key releases"""
if event.key == pygame.K_RIGHT:
self.ship.moving_right = False
elif event.key == pygame.K_LEFT:
# Move the ship to the left
self.ship.moving_left = False
def _fire_bullet(self):
"""Create new bullet and add it to the bullets group"""
if len(self.bullets) < self.settings.bullets_allowed:
new_bullet = Bullet(self)
self.bullets.add(new_bullet)
self.sound_effects.play_shoot()
def _update_bullets(self):
"""Update position of bullets and get rid of old bullets."""
self.bullets.update()
# Get rid of bullets that have disappeared
for bullet in self.bullets.copy():
if bullet.rect.bottom <= 0:
self.bullets.remove(bullet)
self._check_bullet_alien_collisions()
def _check_bullet_alien_collisions(self):
"""Respond to bullet-alien collisions."""
# Remove any bullets and aliens that have collided
collisions = pygame.sprite.groupcollide(self.bullets, self.aliens,
True, True)
if collisions:
for aliens in collisions.values():
self.stats.score += self.settings.alien_points * len(aliens)
self.sb.prep_score()
self.sb.check_high_score()
self.sound_effects.play_alien_hit()
if not self.aliens:
self._start_new_level()
def _start_new_level(self):
"""Begin new level"""
# Destroy existing bullets and create new fleet.
self.bullets.empty()
self._create_fleet()
self.settings.increase_speed()
self.stats.level += 1
self.sb.prep_level()
def _update_aliens(self):
"""Check if fleet is at an edge, then update the positions of all aliens in the fleet"""
self._check_fleet_edges()
self.aliens.update()
if pygame.sprite.spritecollideany(self.ship, self.aliens):
self._ship_hit()
# Look for aliens hitting the bottom of the screen.
self._check_aliens_bottom()
def _create_fleet(self):
"""Create a fleet of aliens"""
# Make an alien
alien = Alien(self)
alien_width, alien_height = alien.rect.size
available_space_x = self.settings.screen_width - (2 * alien_width)
number_aliens_x = available_space_x // (2 * alien_width)
# Determine number of rows of aliens that fit on screen
ship_height = self.ship.rect.height
available_space_y = (self.settings.screen_height - (3 * alien_height) -
ship_height)
number_rows = available_space_y // (2 * alien_height)
# Create full fleet of aliens
for row_number in range(number_rows):
for alien_number in range(number_aliens_x):
self._create_alien(alien_number, row_number)
def _create_alien(self, alien_number, row_number):
# Create and alien and place in row
alien = Alien(self)
alien_width, alien_height = alien.rect.size
alien.x = alien_width + 2 * alien_width * alien_number
alien.rect.x = alien.x
alien.rect.y = alien.rect.height + 2 * alien.rect.height * row_number
self.aliens.add(alien)
def _update_screen(self):
"""Update images on screen, and flip to the new screen"""
self.screen.fill(self.settings.bg_color)
self.ship.blitme()
for bullet in self.bullets.sprites():
bullet.draw_bullet()
self.aliens.draw(self.screen)
# Draw score information
self.sb.show_score()
# Draw the play button if the game is inactive.
if not self.stats.game_active:
self.play_button.draw_button("Play")
self.hard_button.draw_button("Hard",
self.screen.get_rect().bottom,
self.screen.get_rect().left)
self.crazy_button.draw_button("Crazy",
self.screen.get_rect().bottom - 70,
self.screen.get_rect().left)
pygame.display.flip()
def _check_fleet_edges(self):
"""Respond appropriately if any aliens have reached an edge"""
for alien in self.aliens.sprites():
if alien.check_edges():
self._change_fleet_direction()
break
def _change_fleet_direction(self):
"""drop the entire fleet and change the fleet's direction"""
for alien in self.aliens.sprites():
alien.rect.y += self.settings.fleet_drop_speed
self.settings.fleet_direction *= -1
self.sound_effects.play_alien_change_dir()
def _ship_hit(self):
"""Respond to the ship being hit by an alien."""
if self.stats.ships_left > 0:
# Decrement ships_left, update scoreboard
self.stats.ships_left -= 1
self.sb.prep_ships()
# Get rid of any remaining aliens and bullets.
self.aliens.empty()
self.bullets.empty()
# Create a new fleet and center the ship.
self._create_fleet()
self.ship.center_ship()
# Pause
sleep(0.5)
else:
self.stats.game_active = False
self.settings.reset_speed()
pygame.mouse.set_visible(True)
self.stats.update_high_score()
def _check_aliens_bottom(self):
"""Check if any aliens have reached the bottom of the screen."""
screen_rect = self.screen.get_rect()
for alien in self.aliens.sprites():
if alien.rect.bottom >= screen_rect.bottom:
# Treat this the same as if the ship got hit.
self._ship_hit()
break
