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(
(self.settings.screen_width, self.settings.screen_height))
# Full screen
# 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 create 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._create_fleet()
self._start_event_handler()
# MAke the play button
self.play_button = Button(self, "Play")
def _start_event_handler(self):
"""Start event handler"""
self.event_handler = EventHandler()
self._add_accepted_event_types()
self._add_accepted_key_down_type()
self._add_accepted_key_up_type()
def _add_accepted_event_types(self):
"""Add available event types"""
self.event_handler.register_types({
pygame.QUIT:
EventType(sys.exit, False),
pygame.KEYDOWN:
EventType(self._check_keydown_events, True),
pygame.KEYUP:
EventType(self._check_keyup_events, True),
pygame.MOUSEBUTTONDOWN:
EventType(self._check_play_button, False),
})
def _add_accepted_key_down_type(self):
self.event_handler.register_key_down_actions({
pygame.K_RIGHT:
self.ship.move_right,
pygame.K_LEFT:
self.ship.move_left,
pygame.K_UP:
self.ship.move_up,
pygame.K_DOWN:
self.ship.move_down,
pygame.K_SPACE:
self._fire_bullet,
pygame.K_q:
sys.exit,
})
def _add_accepted_key_up_type(self):
self.event_handler.register_key_up_actions({
pygame.K_RIGHT:
self.ship.stop_move_right,
pygame.K_LEFT:
self.ship.stop_move_left,
pygame.K_UP:
self.ship.stop_move_up,
pygame.K_DOWN:
self.ship.stop_move_down,
})
def run_game(self):
"""Start the main loop for the game."""
while True:
self._check_events()
if self.stats.game_active:
self.ship.update()
self._update_bullets()
self._update_aliens()
self._update_screen()
def _update_bullets(self):
"""Update position of bullets and get rid of old bullets"""
# Update bullets position
self.bullets.update()
self._clear_bullets()
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,
dokilla=True,
dokillb=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()
if not self.aliens:
# Destroy existing bullets and create new fleet
self.bullets.empty()
self._create_fleet()
self.settings.increase_speed()
# Increase level.
self.stats.level += 1
self.sb.prep_level()
def _clear_bullets(self):
"""Get rid of bullets that have disappeared."""
for b in self.bullets.copy():
if b.rect.bottom <= 0:
self.bullets.remove(b)
def _update_screen(self):
"""Update images on the screen, and flip to the new screen."""
# Redraw the screen during each pass though the loop
self.screen.fill(self.settings.bg_color)
self.ship.blitme()
for b in self.bullets.sprites():
b.draw_bullet()
self.aliens.draw(self.screen)
# Draw the 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()
# Make the most recently drawn screen visible.
pygame.display.flip()
def _check_events(self):
"""Respond to key presses and mouse events"""
for event in pygame.event.get():
self.event_handler.execute_event(event)
def _check_keyup_events(self, event):
"""Respond to key releases."""
self.event_handler.execute_key_up(event.key)
def _check_keydown_events(self, event):
"""Respond to key presses."""
self.event_handler.execute_key_down(event.key)
def _fire_bullet(self):
"""Create a 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)
def _create_fleet(self):
"""Create the fleet of aliens"""
alien_height, number_aliens_x = self._get_alien_height_and_number_of_aliens_per_line(
)
number_rows = self._get_number_of_rows_of_aliens_based_on_alien_height(
alien_height)
# Create the full fleet of aliens
for row in range(number_rows):
for alien_number in range(number_aliens_x):
self._creat_alien(alien_number, row)
def _get_number_of_rows_of_aliens_based_on_alien_height(
self, alien_height):
"""Base on screen height and alien height, calculate how many line of aliens we can have."""
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)
return number_rows
def _get_alien_height_and_number_of_aliens_per_line(self):
"""
Get alien size, calculate the number of aliens that fit in one row
and return the height of alien and the number.
"""
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)
return alien_height, number_aliens_x
def _creat_alien(self, alien_number, row_number):
"""Create an alien and place it in the 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_height + 2 * alien_height * row_number
self.aliens.add(alien)
def _update_aliens(self):
"""
Check if the fleet is at an edge, then update the positions of all aliens in the fleet
"""
self._check_fleet_edges()
self.aliens.update()
# Look for alien-ship collisions.
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 _check_fleet_edges(self):
"""Respond appropriately if any aliens have reached and 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
def _ship_hit(self):
"""Respond to the ship being hit by an alien."""
if self.stats.ships_left > 0:
# Decrement ships_left.
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
pygame.mouse.set_visible(True)
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
def _check_play_button(self):
"""Start a new game when the player clicks Play."""
mouse_pos = pygame.mouse.get_pos()
button_clicked = self.play_button.rect.collidepoint(mouse_pos)
if button_clicked and not self.stats.game_active:
# Reset the game settings
self.settings.initialize_dynamic_settings()
# Reset the game statistics
self.stats.reset_stats()
self.stats.game_active = True
self.sb.prep_score()
self.sb.prep_level()
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()
# Hide the mouse cursor.
pygame.mouse.set_visible(False)
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(
(self.settings.screen_width, self.settings.screen_height))
# full screen mode
# 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 create a scoreboard.
# need to create it before defining other game elements, such as the ship.
self.stats = GameStats(self)
self.sb = Scoreboard(self)
# Ship constructor needs an instance of AlienInvasion class
self.ship = Ship(self)
self.bullets = pygame.sprite.Group()
self.aliens = pygame.sprite.Group()
self._create_fleet()
# Make the Play button.
self.play_button = Button(self, "Play")
def run_game(self):
"""Start the main loop for the game."""
while True:
self._check_events()
if self.stats.game_active:
self.ship.update()
self._update_bullets()
self._update_aliens()
self._update_screen()
# In Python, a single leading underscore indicates a helper method. Kinda a private method
def _check_events(self):
"""Respond to keypresses and mouse events."""
# To access the events that Pygame detects, we’ll use the pygame.event.get() function. This function returns a list of events
# that have taken place since the last time this function was called.
# Any keyboard or mouse event will cause this for loop to run.
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)
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 the game settings.
self.settings.initialize_dynamic_settings()
# Reset the game statistics.
self.stats.reset_stats()
self.stats.game_active = True
self.sb.prep_score()
self.sb.prep_level()
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()
# Hide the mouse cursor.
pygame.mouse.set_visible(False)
def _check_keydown_events(self, event):
"""Respond to keypresses."""
if event.key == pygame.K_RIGHT:
self.ship.moving_right = True
elif event.key == pygame.K_LEFT:
self.ship.moving_left = True
elif event.key == pygame.K_q:
sys.exit()
elif event.key == pygame.K_SPACE:
self._fire_bullet()
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:
self.ship.moving_left = False
def _fire_bullet(self):
"""Create a 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)
def _update_bullets(self):
"""Update position of bullets and get rid of old bullets."""
# Update bullet positions.
# When you call update() on a group, the group automatically calls update() for each sprite in the group. The line
# self.bullets.update() calls bullet.update() for each bullet we place in the group bullets.
self.bullets.update()
# Get rid of bullets that have disappeared. When you use a for loop with a list (or a group in Pygame), Python expects that
# the list will stay the same length as long as the loop is running. Because we can’t remove items from a list or group
# within a for loop, we have to loop over a copy of the group.
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()
if not self.aliens:
# Destroy existing bullets and create new fleet.
self.bullets.empty()
self._create_fleet()
self.settings.increase_speed()
# Increase level.
self.stats.level += 1
self.sb.prep_level()
def _update_aliens(self):
"""
Check if the fleet is at an edge,
then update the positions of all aliens in the fleet.
"""
self._check_fleet_edges()
self.aliens.update()
# Look for alien-ship collisions.
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 the fleet of aliens."""
# Create an alien and find the number of aliens in a row.
# Spacing between each alien is equal to one alien width.
alien = Alien(self)
alien_width, alien_height = alien.rect.size
alien_width = alien.rect.width
available_space_x = self.settings.screen_width - (2 * alien_width)
number_aliens_x = available_space_x // (2 * alien_width)
# Determine the number of rows of aliens that fit on the 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 the 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 an alien and place it in the 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 _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
def _update_screen(self):
"""Update images on the 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()
# When you call draw() on a group, Pygame draws each element in the group at the position defined by its rect attribute. The
# draw() method requires one argument: a surface on which to draw the elements from the group
self.aliens.draw(self.screen)
# Draw the 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()
# Make the most recently drawn screen visible.
pygame.display.flip()
def _ship_hit(self):
"""Respond to the ship being hit by an alien."""
if self.stats.ships_left > 0:
# Decrement ships_left, and 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
pygame.mouse.set_visible(True)
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
