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pygame alien invasion the bullets are not moving across the screen [duplicate]

This question already has answers here:
How can i shoot a bullet with space bar?
(1 answer)
How do I stop more than 1 bullet firing at once?
(1 answer)
Closed 2 years ago.
so I was doing the exercise of python crash course 12-6. which places a ship on the left side of the screen and allows the player to move the ship up and down. Make the ship fire the bullet that travels right across the screen when the player presses the space-bar.
I've tried to print the length of the bullets, the animation runs which means it is recognizing that the button is being pressed and the bullets appear but don't move. The bullet appears but stays frozen. It seems the for loop has something to do with it.
I've tried to compare the Alian Invasion code three times which is explained in the chapter for this exercise, which sound stupid but i don't see anything obviously wrong to me.
I'm new to python and pygame and even to stackoverflow, any help will be highly appreciated.
The below is the main code to run the game.
import pygame
import sys
from sideways_shooter import SidewaysShooter
from stone import Stone
from settings import Settings
class SidewaysShooterGame:
def __init__(self):
pygame.init()
self.settings = Settings()
self.screen = pygame.display.set_mode(
(self.settings.screen_width, self.settings.screen_height))
pygame.display.set_caption("Sideways Shooter Game")
self.sideways_shooter = SidewaysShooter(self)
self.stones = pygame.sprite.Group()
def run_game(self):
while True:
self._check_events()
self.sideways_shooter.update()
self._stones_update()
self._update_screen()
def _stones_update(self):
self.stones.update()
for stone in self.stones.copy():
if stone.rect.left >= self.sideways_shooter.screen_rect.right:
self.stones.remove(stone)
def _check_events(self):
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)
def _check_keydown_events(self, event):
if event.key == pygame.K_UP:
self.sideways_shooter.moving_up = True
elif event.key == pygame.K_DOWN:
self.sideways_shooter.moving_down = True
elif event.key == pygame.K_q:
sys.exit()
elif event.key == pygame.K_SPACE:
self._throw_stones()
def _check_keyup_events(self,event):
if event.key == pygame.K_UP:
self.sideways_shooter.moving_up = False
elif event.key == pygame.K_DOWN:
self.sideways_shooter.moving_down = False
def _throw_stones(self):
if len(self.stones) < self.settings.stones_allowed:
new_stone = Stone(self)
self.stones.add(new_stone)
def _update_screen(self):
self.screen.fill(self.settings.bg_color)
self.sideways_shooter.blitme()
for stone in self.stones:
stone.draw_stone()
pygame.display.flip()
if __name__ == '__main__':
ss_game = SidewaysShooterGame()
ss_game.run_game()
The below are the classes and methods that contains assets and attributes for the main code project.
sideway_shooter file
import pygame
class SidewaysShooter:
def __init__(self, ss_game):
self.screen = ss_game.screen
self.settings = ss_game.settings
self.screen_rect = ss_game.screen.get_rect()
self.image = pygame.image.load('images/resized_shooter_bmp_file.bmp')
self.rect = self.image.get_rect()
self.rect.midleft = self.screen_rect.midleft
self.y = float(self.rect.y)
self.moving_up = False
self.moving_down = False
def update(self):
if self.moving_up and self.rect.top > 0:
self.y -= self.settings.speed
if self.moving_down and self.rect.bottom < self.screen_rect.bottom:
self.y += self.settings.speed
self.rect.y = self.y
def blitme(self):
self.screen.blit(self.image, self.rect)
stone file
import pygame
from pygame.sprite import Sprite
class Stone(Sprite):
def __init__(self, ss_game):
super().__init__()
self.screen = ss_game.screen
self.settings = ss_game.settings
self.color = self.settings.stone_color
self.rect = pygame.Rect(0, 0, self.settings.stone_width,
self.settings.stone_height)
self.rect.midright = ss_game.sideways_shooter.rect.midright
self.x = float(self.rect.x)
def upate(self):
self.x += self.settings.stone_speed
self.rect.x = self.x
def draw_stone(self):
pygame.draw.rect(self.screen, self.color, self.rect)
settings file
class Settings:
def __init__(self):
self.screen_width = 1400
self.screen_height = 700
self.bg_color = (255, 255, 255)
self.speed = 1.5
self.stone_color = (60, 60, 60)
self.stone_width = 15
self.stone_height = 3
self.stone_speed = 1.0
self.stones_allowed = 3

Projectiles only move if i hold the fire key down

Previously in my projectiles module, I had a class that handled each direction of fire seperately (a class for firing up, down, left and right) and this did it's job. However, now that I'm trying to incorporate shot speed and other things into the class, having 4 seperate classes is just too messy and so I tried to trim it down so that I only have one class for all projectiles fired.
However, now that I have done this, when I fire a projectile, it will only move so long as I am holding the fire button ('a' key if firing left) down. Also, if I fire left, then fire right, the projectile that was previously travelling left will begin to travel right instead.
My question is; How do I handle the projectiles so that when I fire one, it no longer accepts updates and travels in a straight line?
This is my working code;
Main game module
import pygame
from constants import *
from player import Player
from Projectile import Projectiles
pygame.init()
screen = pygame.display.set_mode([500, 500])
pygame.display.set_caption('Labyrinth')
# Spawn player
player = Player(50, 50)
all_sprites_list = pygame.sprite.Group()
all_sprites_list.add(player)
projectile_list = pygame.sprite.Group()
clock = pygame.time.Clock()
done = False
# ----- Event Loop
while not done:
for event in pygame.event.get():
if event.type == pygame.QUIT:
done = True
elif event.type == pygame.KEYDOWN:
if event.key == ord('a'):
player.changespeed(-3, 0)
elif event.key == ord('d'):
player.changespeed(3, 0)
elif event.key == ord('w'):
player.changespeed(0, -3)
elif event.key == ord('s'):
player.changespeed(0, 3)
elif event.key == pygame.K_LEFT:
projectile = Projectiles(0, 0)
projectile.rect.x = player.rect.x
projectile.rect.y = player.rect.y
elif event.key == pygame.K_RIGHT:
projectile = Projectiles(0, 0)
projectile.rect.x = player.rect.x
projectile.rect.y = player.rect.y
elif event.key == pygame.K_UP:
projectile = Projectiles(0, 0)
projectile.rect.x = player.rect.x
projectile.rect.y = player.rect.y
elif event.key == pygame.K_DOWN:
projectile = Projectiles(0, 0)
projectile.rect.x = player.rect.x
projectile.rect.y = player.rect.y
try:
if projectile:
projectile_list.add(projectile)
except:
pass
elif event.type == pygame.KEYUP:
if event.key == ord('a'):
player.changespeed(3, 0)
elif event.key == ord('d'):
player.changespeed(-3, 0)
elif event.key == ord('w'):
player.changespeed(0, 3)
elif event.key == ord('s'):
player.changespeed(0, -3)
# ----- Game Logic
all_sprites_list.update()
projectile_list.update()
screen.fill(GREEN)
all_sprites_list.draw(screen)
projectile_list.draw(screen)
pygame.display.flip()
clock.tick(60)
pygame.quit()
Player module
from constants import *
import pygame
import time
from datetime import datetime, timedelta
class Player(pygame.sprite.Sprite):
def __init__(self, x, y):
super().__init__()
self.image = pygame.Surface([15, 15])
self.image.fill(BLACK)
self.rect = self.image.get_rect()
self.rect.x = x
self.rect.y = y
self.change_x = 0
self.change_y = 0
def changespeed(self, x, y):
self.change_x += x
self.change_y += y
def update(self):
self.rect.x += self.change_x
self.rect.y += self.change_y
Projectile module
import pygame
from constants import *
class Projectiles(object):
def __init__(self, x, y):
super().__init__()
self.image = pygame.Surface([4, 4])
self.image.fill(RED)
self.rect = self.image.get_rect()
def update(self):
key = pygame.key.get_pressed()
if key[pygame.K_UP]:
self.rect.y -= 5
if key[pygame.K_DOWN]:
self.rect.y += 5
if key[pygame.K_LEFT]:
self.rect.x -= 5
if key[pygame.K_RIGHT]:
self.rect.x += 5
As always any help would be much appreciated!

The first problem is that you only create ONE projectile. Your class is called Projectiles which is misleading because it's only one object not multiple. This causes the projectile to be controlled even after firing.
Also, the reason why the projectile only moves while you press a key is that in the update() method, you only add to the projectiles x or y coordinate when e.g. key[pygame.K_UP]: is true.
So, to fix this issues you will have to change the way your game handles projectiles.
If I understand your question right, you want to have multiple projectiles at once.
The way to implement this is to use a collection of projectiles.
Game
//nothing changed till here
elif event.key == pygame.K_LEFT:
p = Projectile(player.rect.x, player.rect.y, -5, 0)
projectile_list.add(p)
elif event.key == pygame.K_RIGHT:
p = Projectile(player.rect.x, player.rect.y, 5, 0)
projectile_list.add(p)
elif event.key == pygame.K_UP:
p = Projectile(player.rect.x, player.rect.y, 0, -5)
projectile_list.add(p))
elif event.key == pygame.K_DOWN:
p = Projectile(player.rect.x, player.rect.y, 0, 5)
projectile_list.add(p)
// moved the part where you append the projectile to in the if statement
# ----- Game Logic
all_sprites_list.update()
projectile_list.update()
screen.fill(GREEN)
all_sprites_list.draw(screen)
projectile_list.draw(screen)
pygame.display.flip()
clock.tick(60)
pygame.quit()
Projectile:
import pygame
from constants import *
// projectile needs to extend Sprite
class Projectile(pygame.sprite.Sprite):
def __init__(self, x, y, x_speed, y_speed):
super().__init__()
self.image = pygame.Surface([4, 4])
self.image.fill(RED)
self.rect = self.image.get_rect()
self.rect.x = x
self.rect.y = y
self.x_speed = x_speed
self.y_speed = y_speed
def update(self):
self.rect.x += self.x_speed
self.rect.y += self.y_speed
Im not so familiar with Pygame but I hope this will help you at least somehow.

I have never used PyGame but one can see that your update() method in the Projectiles class depends on key press while it should depend on elapsed time instead.
Your projectile moves 5 units per key press, not 5 units per game tick once launched.

Pygame: bullets sticks to the screen

My problem is very simple. The bullets I fire sticks to the screen if I shoot fast. If I shoot slowly, they don't stick. Anyone have an idea how this phenomenon occurs?
screenshot of the bullets sticking to the screen
Below I have entered the code. I follow this default game flowchart:
I am curious about the origin of the problem. Is it the code or hardware?
import sys
import pygame
from pygame.sprite import Sprite
from pygame.sprite import Group
# pygame initializing
pygame.init()
#create the screen surface
screen = pygame.display.set_mode((800, 700))
class Color():
def __init__(self):
self.black = (0, 0, 0)
self.white = (255, 255, 255)
self.red = (255, 0, 0)
self.green = (0, 255, 0)
self.green_lambda = (10, 255, 150)
self.blue = (0, 0, 255)
# set up the colors
color = Color() # make an instance of this class - this makes some colors available
class Spaceship(Sprite):
"""
This class represents the Spaceship.
It derives from the "Sprite" class in Pygame.
"""
def __init__(self):
""" Constructor"""
# Call the parent class (Sprite) constructor
super().__init__()
width = 22
height = 32
self.screen = screen
self.image = pygame.Surface((width, height))
self.image.fill(color.black)
self.image.set_colorkey(color.black)
pygame.draw.polygon(self.image, color.green_lambda, [[10,0],[15,22],[20,30],[10,27],[0,30],[5,22]],2)
self.rect = self.image.get_rect()
self.screen_rect = self.screen.get_rect()
self.rect.centerx = self.screen_rect.centerx
self.rect.bottom = self.screen_rect.bottom
# As the rect method only take integers we store a
# This value is only used at the beginning, i.e. before the game loop starts
self.center_x = self.rect.centerx
self.center_y = self.rect.centery
class Bullet(Sprite):
"""
This class represents the bullets.
It derives from the "Sprite" class in Pygame.
"""
def __init__(self):
# Call the parent class (Sprite) constructor
super().__init__()
self.image = pygame.Surface((8,10))
self.image.fill(color.red)
self.image.set_colorkey((color.red))
pygame.draw.ellipse(self.image, color.green, [1, 0, 5, 8], 2)
self.rect = self.image.get_rect()
self.rect.centerx = defender.rect.centerx
self.rect.bottom = defender.rect.top
# def function to move the bullets
def update_pos(self):
self.rect.y -= bullet_speed
# create spaceship instance
defender = Spaceship()
# create group to store sprites in
all_sprites_list = Group()
all_sprites_list.add(defender)
ship_speed = 0.5
bullet_speed = 3
def run_game():
m_right = False
m_left = False
m_up = False
m_down = False
new_bullet = False
while True:
"""This is the user interaction section"""
for event in pygame.event.get():
if event.type == pygame.KEYDOWN:
if event.key == pygame.K_ESCAPE:
sys.exit()
elif event.key == pygame.K_RIGHT:
m_right = True
elif event.key == pygame.K_LEFT:
m_left = True
elif event.key == pygame.K_UP:
m_up = True
elif event.key == pygame.K_DOWN:
m_down = True
elif event.key == pygame.K_SPACE:
new_bullet = Bullet()
#print(dir(new_bullet))
all_sprites_list.add(new_bullet)
if event.type == pygame.KEYUP:
if event.key == pygame.K_RIGHT:
m_right = False
elif event.key == pygame.K_LEFT:
m_left = False
elif event.key == pygame.K_UP:
m_up = False
elif event.key == pygame.K_DOWN:
m_down = False
"""Below is the game logic, which gets input from the user interaction
section and more"""
# Movement of spaceship depending on the flag boolean value and on screen width and height
if m_right and defender.rect.right < defender.screen_rect.right:
defender.center_x += ship_speed
if m_left and defender.rect.left > defender.screen_rect.left:
defender.center_x -= ship_speed
if m_up and defender.rect.top > defender.screen_rect.top:
defender.center_y -= ship_speed
if m_down and defender.rect.bottom < defender.screen_rect.bottom:
defender.center_y += ship_speed
# The cumulative value (which is a float number) for the spaceships movement
# is given to the spaceship rect variable (which can only be integer) now.
# This enables fine adjusting of the speed
defender.rect.centerx = defender.center_x
defender.rect.centery = defender.center_y
all_sprites_list.update()
screen.fill(color.black)
if new_bullet:
new_bullet.update_pos()
# Below the bullets which leaves the screen display are deleted
if new_bullet.rect.bottom < defender.screen_rect.top:
all_sprites_list.remove(new_bullet)
all_sprites_list.draw(screen)
print(all_sprites_list)
pygame.display.flip()
run_game()

instead of just updating the position of new_bullet
# if new_bullet:
# new_bullet.update_pos()
# # Below the bullets which leaves the screen display are deleted
# if new_bullet.rect.bottom < defender.screen_rect.top:
# all_sprites_list.remove(new_bullet)
update the position of all bullets
for bullet in all_sprites_list:
if isinstance(bullet,Bullet):
bullet.update_pos()
if bullet.rect.bottom < defender.screen_rect.top:
all_sprites_list.remove(bullet)
del bullet

Joran Beasley's answer is correct. I'd just like to point out that you can also put the behavior of the sprites into their update methods which get called automatically when you call all_sprites_list.update(). You can actually move most of the code in the while loop to the update methods.
I've got an example with these changes and some more tips in the comments (a quick code review):
import pygame
from pygame.sprite import Sprite
from pygame.sprite import Group
# I'd just define some global constants for the colors.
BLACK = (0, 0, 0)
GREEN = (0, 255, 0)
GREEN_LAMBDA = (10, 255, 150)
class Spaceship(Sprite):
"""This class represents the Spaceship."""
def __init__(self, screen):
"""Constructor"""
super().__init__()
self.screen = screen
# pygame.SRCALPHA makes the surface transparent.
self.image = pygame.Surface((22, 32), pygame.SRCALPHA)
pygame.draw.polygon(
self.image, GREEN_LAMBDA,
[[10,0],[15,22],[20,30],[10,27],[0,30],[5,22]], 2
)
self.screen_rect = self.screen.get_rect()
# You can pass the position as the midbottom argument to `get_rect`.
self.rect = self.image.get_rect(midbottom=self.screen_rect.midbottom)
self.center_x = self.rect.centerx
self.center_y = self.rect.centery
# I've removed the `m_right`, etc. variables and just set the speed
# of the sprite in the event loop.
self.max_speed = 3.5
self.speed_x = 0
self.speed_y = 0
def update(self):
# Move the sprite.
self.center_x += self.speed_x
self.center_y += self.speed_y
self.rect.centerx = self.center_x
self.rect.centery = self.center_y
# Keep the sprite on the screen.
if not self.screen_rect.contains(self.rect):
self.rect.clamp_ip(self.screen_rect)
self.center_x, self.center_y = self.rect.center
class Bullet(Sprite):
"""This class represents the bullets."""
def __init__(self, pos):
super().__init__()
self.image = pygame.Surface((8, 10), pygame.SRCALPHA)
pygame.draw.ellipse(self.image, GREEN, [1, 0, 5, 8], 2)
self.rect = self.image.get_rect(midbottom=pos)
self.speed = 3 # The speed is now an attribute.
def update(self):
self.rect.y -= self.speed
if self.rect.top < 0:
self.kill() # Remove the sprite from all groups.
def run_game():
pygame.init()
screen = pygame.display.set_mode((800, 700))
clock = pygame.time.Clock() # Use a clock to limit the frame rate.
defender = Spaceship(screen)
all_sprites = Group() # Changed the name because groups are not lists.
all_sprites.add(defender)
while True:
for event in pygame.event.get():
if event.type == pygame.QUIT:
return
elif event.type == pygame.KEYDOWN:
if event.key == pygame.K_ESCAPE:
return
elif event.key == pygame.K_RIGHT:
defender.speed_x = defender.max_speed
elif event.key == pygame.K_LEFT:
defender.speed_x = -defender.max_speed
elif event.key == pygame.K_UP:
defender.speed_y = -defender.max_speed
elif event.key == pygame.K_DOWN:
defender.speed_y = defender.max_speed
elif event.key == pygame.K_SPACE:
new_bullet = Bullet(defender.rect.midtop) # Pass the pos.
all_sprites.add(new_bullet)
elif event.type == pygame.KEYUP:
if event.key == pygame.K_RIGHT and defender.speed_x > 0:
defender.speed_x = 0
elif event.key == pygame.K_LEFT and defender.speed_x < 0:
defender.speed_x = 0
elif event.key == pygame.K_UP and defender.speed_y < 0:
defender.speed_y = 0
elif event.key == pygame.K_DOWN and defender.speed_y > 0:
defender.speed_y = 0
all_sprites.update() # Calls the update methods of all sprites.
screen.fill(BLACK)
all_sprites.draw(screen)
pygame.display.flip()
clock.tick(60) # Limit the frame rate to 60 FPS.
run_game()

moving a sprite while holding down a key not working

So im trying the make my sprite move constantly when im holding my arrow keys, but i need to keep pressing it to move it. any idea why?
here's my code:
yes i have imported pygame and everything
class Block(pygame.sprite.Sprite):
def __init__(self, color = blue,widht = 64, height = 64):
super(Block, self).__init__()
self.image = pygame.Surface((widht, height))
self.image.fill(color)
self.rect = self.image.get_rect()
self.sound = pygame.mixer.Sound("2dSounds/Walk.wav")
self.hspeed = 0
self.vspeed = 0
to update the sprite, so it changes places depending what key i press
def update(self):
self.rect.x += self.hspeed
self.rect.y += self.vspeed
to change the speed using a_block.change_speed(...)
def change_speed(self, hspeed, vspeed):
self.hspeed += hspeed
self.vspeed += vspeed
to set the position of the sprite when i first create it
def set_position(self, x, y):
self.rect.x = x
self.rect.y = y
to set a image for my sprite i just created
def set_image(self, filename = None):
if(filename != None):
self.image = pygame.image.load(filename)
self.rect = self.image.get_rect()
to play a sound
def play_sound():
self.sound.play()
the gameloop
def game_loop():
a_block = Block()
global event
gameDisplay.fill(white)
#Quit
gameExit = False
while not gameExit:
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit()
quit()
the controls that dont work
if event.type == pygame.KEYDOWN:
if event.key == pygame.K_LEFT:
a_block.change_speed(-20, 0)
if event.key == pygame.K_RIGHT:
a_block.change_speed(20, 0)
if event.key == pygame.K_UP:
a_block.change_speed(0, -20)
if event.key == pygame.K_DOWN:
a_block.change_speed(0, 20)
if event.type == pygame.KEYUP:
if event.key == pygame.K_LEFT:
a_block.change_speed(0, 0)
if event.key == pygame.K_RIGHT:
a_block.change_speed(0, 0)
if event.key == pygame.K_UP:
a_block.change_speed(0, 0)
if event.key == pygame.K_DOWN:
a_block.change_speed(0, 0)
To draw a_block and other things
block_group = pygame.sprite.Group()
gameDisplay.fill(white)
a_block.set_image('2dImages/brick.png')
a_block.set_position(display_width/2, display_height/2)
a_block.update()
block_group.add(a_block)
block_group.draw(gameDisplay)
update display
pygame.display.update()
clock.tick(60)
thanks alot in advance!!

At the beginning of your code (but after you call pygame.init()), add the following line of code:
pygame.key.set_repeat(10)
This will post keyboard events to the event queue every 10 milliseconds even if the key was already pressed.

Is there a better way to move a sprite using the keyboard with Pygame?

Currently, I have small image that I move using the D and A keys on the keyboard. The code works just how I want it to, but it seems to be a bit unnecessarily complicated. Is there a more efficient way of doing this?
In the main loop, my code checks to see what key is pressed through the events, but after that, if a key is no longer pressed, it checks to see if another key is pressed, just in case a user pressed a key while another key was initially pressed.
Here is my code:
import pygame
import sys
from pygame.locals import *
SCREENX = 640
SCREENY = 480
LEFT = 'left'
RIGHT = 'right'
class Character(pygame.sprite.Sprite):
def __init__(self, image_file):
super().__init__()
temp_image = pygame.image.load(image_file)
self.image = pygame.transform.scale(temp_image, (100, 100))
self.rect = self.image.get_rect()
self.moving = False
self.direction = RIGHT
def start_move(self, direction):
self.moving = True
if direction != self.direction:
self.image = pygame.transform.flip(self.image, True, False)
self.direction = direction
def stop_move(self):
if self.moving:
self.moving = False
def move(self):
if self.direction == RIGHT:
self.rect.x += 5
if self.direction == LEFT:
self.rect.x -= 5
def update(self):
if self.moving:
self.move()
def main():
pygame.init()
surface = pygame.display.set_mode((SCREENX, SCREENY))
clock = pygame.time.Clock()
sprites = pygame.sprite.Group()
girl = Character("assets/girl.png")
girl.rect.x = SCREENX/2
girl.rect.y = SCREENY - girl.rect.height
sprites.add(girl)
while True:
for event in pygame.event.get():
if event.type == QUIT:
pygame.quit()
sys.exit()
if event.type == KEYDOWN:
if not girl.moving:
if event.key == K_d:
girl.start_move(RIGHT)
if event.key == K_a:
girl.start_move(LEFT)
if event.type == KEYUP:
if event.key == K_a or event.key == K_d:
girl.stop_move()
keys_pressed = pygame.key.get_pressed()
if keys_pressed[K_d]:
girl.start_move(RIGHT)
if keys_pressed[K_a]:
girl.start_move(LEFT)
surface.fill((255, 255, 255))
sprites.update()
sprites.draw(surface)
pygame.display.update()
clock.tick(60)
if __name__ == '__main__':
main()

Yes, you can get rid of most of the event handling, you can generalize your main loop, and you can get rid of some fields of your Character class.
See my explanatory notes in the comments:
import pygame
import sys
from pygame.locals import *
SCREENX = 640
SCREENY = 480
class Character(pygame.sprite.Sprite):
def __init__(self, image_file):
pygame.sprite.Sprite.__init__(self)
temp_image = pygame.image.load(image_file)
# only to the flipping of the image once
self.image_r = pygame.transform.scale(temp_image, (100, 100))
self.image_l = pygame.transform.flip(self.image_r, True, False)
self.image = self.image_l
self.rect = self.image.get_rect()
def update(self, pressed_keys):
move = 0
if pressed_keys[K_d]: move += 1
if pressed_keys[K_a]: move -= 1
self.rect.move_ip(move*5, 0)
# check which direction we're facing and set the image
self.image = self.image_l if move < 0 else self.image_r
def main():
pygame.init()
surface = pygame.display.set_mode((SCREENX, SCREENY))
clock = pygame.time.Clock()
sprites = pygame.sprite.Group()
girl = Character("assets/girl.png")
girl.rect.x = SCREENX / 2
girl.rect.y = SCREENY - girl.rect.height
sprites.add(girl)
while True:
for event in pygame.event.get():
# since we are in a function, we can simply return.
# we don't care here what happens after we quit the main loop
if event.type == QUIT: return pygame.quit()
# get all pressed keys, and just let all sprites
# decide what they want to do with it
keys_pressed = pygame.key.get_pressed()
# you could wrap this information in a more
# general container represeting the game state
# See how the game loop does not care what a
# Sprite does with this information
sprites.update(keys_pressed)
surface.fill((255, 255, 255))
sprites.draw(surface)
pygame.display.update()
clock.tick(60)
if __name__ == '__main__':
main()