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Import a player icon and replace a block

Im new to python and im currently making a simple pygame but I can not grasp the concept of sprites. I want to replace the moving block with a player icon that I created.
Do I need to make a group just for one object or is there a way just to add the player without any groups?
from pygame import sprite
import pygame, sys
from pygame.locals import*
from pynput.keyboard import Key, Controller
class Player(pygame.sprite.Sprite):
def __init__(self, picture_path):
super().__init__()
self.image = pygame.image.load(picture_path)
self.rect = self.image.get_rect()
def main():
pygame.init()
DISPLAY=pygame.display.set_mode((1280,720),0,32)
pygame.display.set_caption('Der Sammler')
WHITE=(255,255,255)
BLUE=(0,0,255)
DISPLAY.fill(WHITE)
x = 0
y = 0
velocity1 = 0
acceleration = 0.1
velocity = pygame.Vector2()
velocity.xy = 3, 0
player = Player("player.png")
while True:
pygame.draw.rect(DISPLAY, BLUE, (x,y,50,50))
x += velocity.x
if x+ 50 > DISPLAY.get_width():
velocity.x = -3
if x < 0:
velocity.x = 3
pressed_keys = pygame.key.get_pressed()
for event in pygame.event.get():
if event.type==QUIT:
pygame.quit()
sys.exit()
DISPLAY.fill((255, 255, 255))
pygame.draw.rect(DISPLAY,BLUE, (x,y, 50, 50))
y += velocity1
velocity1 += acceleration
if pressed_keys[pygame.K_SPACE]:
velocity1 = -3
pygame.display.update()
pygame.time.delay(10)
main()

Add an update method to Player and put the movement and gravity algorithm in that method:
class Player(pygame.sprite.Sprite):
def __init__(self, picture_path):
super().__init__()
self.image = pygame.image.load(picture_path)
self.rect = self.image.get_rect()
self.velocity = pygame.Vector2(3, 0)
self.acceleration = 0.1
def update(self, dispaly):
pressed_keys = pygame.key.get_pressed()
self.rect.x += self.velocity.x
if self.rect.right >= dispaly.get_width():
self.velocity.x = -3
if self.rect.left < 0:
self.velocity.x = 3
self.rect.y += self.velocity.y
self.velocity.y += self.acceleration
if pressed_keys[pygame.K_SPACE]:
self.velocity.y = -3
Add the player to a pygame.sprite.Group:
sprites = pygame.sprite.Group(player)
Call sprites.update() and sprites.draw() in the application loop to update the position of the player and to move the player:
while True:
for event in pygame.event.get():
if event.type==QUIT:
pygame.quit()
sys.exit()
sprites.update(DISPLAY)
DISPLAY.fill((255, 255, 255))
sprites.draw(DISPLAY)
pygame.display.update()
Also see How can I add objects to a "pygame.sprite.Group()"?.
Complete example:
import pygame, sys
from pygame.locals import*
class Player(pygame.sprite.Sprite):
def __init__(self, picture_path):
super().__init__()
self.image = pygame.image.load(picture_path)
self.rect = self.image.get_rect()
self.velocity = pygame.Vector2(3, 0)
self.acceleration = 0.1
def update(self, dispaly):
pressed_keys = pygame.key.get_pressed()
self.rect.x += self.velocity.x
if self.rect.right >= dispaly.get_width():
self.velocity.x = -3
if self.rect.left < 0:
self.velocity.x = 3
self.rect.y += self.velocity.y
self.velocity.y += self.acceleration
if pressed_keys[pygame.K_SPACE]:
self.velocity.y = -3
if self.rect.bottom > dispaly.get_height():
self.rect.bottom = dispaly.get_height()
self.velocity.y = 0
def main():
pygame.init()
DISPLAY=pygame.display.set_mode((1280,720),0,32)
pygame.display.set_caption('Der Sammler')
clock = pygame.time.Clock()
WHITE=(255,255,255)
BLUE=(0,0,255)
DISPLAY.fill(WHITE)
player = Player("player.png")
sprites = pygame.sprite.Group(player)
while True:
for event in pygame.event.get():
if event.type==QUIT:
pygame.quit()
sys.exit()
sprites.update(DISPLAY)
DISPLAY.fill((255, 255, 255))
sprites.draw(DISPLAY)
pygame.display.update()
clock.tick(100)
main()

How do you use sprite groups?

I get the error message 'Enemy' object has no attribute '_Sprite__g' and I have no idea how to use the sprite groups. I'm trying to get them to spawn randomly across the x-axis only.
import pygame, os, random
pygame.init()
FPS=60
SCREEN = pygame.display.set_mode((400,500))
pygame.display.set_caption('caption')
x=50
y=450
vel = 3
width = 20
height = 20
class Player(object):
def __init__(self,x,y,width,height):
self.x = x
self.y = y
self.width = width
self.height = height
self.vel = 3
self.image = pygame.Surface((width, height))
self.image.fill((0,0,0))
def draw(self,SCREEN):
SCREEN.blit(self.image, (self.x,self.y))
class B():
def __init__(self,x,y,radius, color):
self.x = x
self.y = y
self.color = color
self.radius = radius
self.vel = vel
def draw(self,SCREEN):
pygame.draw.circle(SCREEN, self.color, (self.x,self.y),self.radius)
class Enemy(pygame.sprite.Sprite):
def __init__(self):
self.image = pygame.Surface((20,20))
self.x = random.randrange (0,400)
self.y = 500
self.speed = random.randrange(1,3)
def draw (self,SCREEN):
SCREEN.blit(self.image,(self.x,self.y))
player = Player(x, y, width, height)
bullets = []
enemies = pygame.sprite.Group()
# Main loop
running = True
clock = pygame.time.Clock()
while running:
clock.tick(FPS)
for event in pygame.event.get():
if event.type == pygame.QUIT:
running = False
for bullet in bullets:
if bullet.x < 450 and bullet.x >0:
bullet.x += bullet.vel
else:
bullets.pop(bullets.index(bullet))
keys = pygame.key.get_pressed()
if keys[pygame.K_SPACE]:
if len(bullets)< 5:
bullets.append(B(round(player.x + player.width //2), round(player.y + player.height//2),3, (0,0,0)))
if keys[pygame.K_w] and player.y > 30 - player.width - player.vel:
player.y -= player.vel
if keys[pygame.K_s] and player.y < 500 - player.width - player.vel:
player.y += player.vel
SCREEN.fill((190, 232, 220))
player.draw(SCREEN)
for bullet in bullets:
bullet.draw(SCREEN)
for i in range (8):
e = Enemy()
enemies.add(e)
pygame.display.update()
pygame.quit()

the obects need to be derives from pygame.sprite.Sprite. The base class needs to be initialized as well. Use super() to delegate to the base class constructor. e.g.:
class Player(object):
def __init__(self,x,y,width,height):
super().__init__()
# [...]
pygame.sprite.Group.draw() and pygame.sprite.Group.update() are methods which are provided by pygame.sprite.Group.
The former delegates the to the update method of the contained pygame.sprite.Sprites - you have to implement the method. See pygame.sprite.Group.update():
Calls the update() method on all Sprites in the Group [...]
The later uses the image and rect attributes of the contained pygame.sprite.Sprites to draw the objects - you have to ensure that the pygame.sprite.Sprites have the required attributes. See pygame.sprite.Group.draw():
Draws the contained Sprites to the Surface argument. This uses the Sprite.image attribute for the source surface, and Sprite.rect. [...]
Therefore the Sprite class must have the attributes .rect and .image. However you don't need the draw method:
class Player(pygame.sprite.Sprite):
def __init__(self,x,y,width,height):
super().__init__()
self.vel = 3
self.image = pygame.Surface((width, height))
self.image.fill((0,0,0))
self.rect = self.image.get_rect(topleft = (x, y))
Create a transparent pygame.Surface with the SRCALPHA flag and draw a circle on it:
class B(pygame.sprite.Sprite):
def __init__(self,x,y,radius, color):
super().__init__()
self.x = x
self.y = y
self.color = color
self.radius = radius
self.vel = vel
self.image = pygame.Surface((self.radius * 2, self.radius * 2), pygame.SRCALPHA)
pygame.draw.circle(self.image, self.color, (self.radius, self.radius), self.radius)
self.rect = self.image.get_rect(center = (self.x, self.y))
Add pygame.sprite.Groups for all sprites. add() the player, the enemies and bullets to the Groups:
enemies = pygame.sprite.Group()
bullets = pygame.sprite.Group()
all_sprites = pygame.sprite.Group()
all_sprites.add(player)
for i in range (8):
e = Enemy()
enemies.add(e)
all_sprites.add(e)
Draw the Sprites in the all_sprites Group with pygame.sprite.Group.draw. Remove a Sprite (form all Groups) with kill:
while running:
# [...]
for bullet in bullets:
if 0 < bullet.rect.y < 500:
bullet.rect.y -= bullet.vel
else:
bullet.kill()
# [...]
all_sprites.draw(SCREEN)
Use the keyboard event instead of pygame.key.get_pressed() to fire a bullet. See How do I stop more than 1 bullet firing at once?:
The collision of the enemies and bullets can be detected with pygame.sprite.groupcollide(). When the doKill arguments are set True, the sprites will be automatically removed:
pygame.sprite.groupcollide(bullets, enemies, True, True)
Complete example:
import pygame, os, random
pygame.init()
FPS=60
SCREEN = pygame.display.set_mode((400,500))
pygame.display.set_caption('caption')
x=50
y=450
vel = 3
width = 20
height = 20
class Player(pygame.sprite.Sprite):
def __init__(self,x,y,width,height):
super().__init__()
self.vel = 3
self.image = pygame.Surface((width, height))
self.image.fill((0,0,0))
self.rect = self.image.get_rect(topleft = (x, y))
class B(pygame.sprite.Sprite):
def __init__(self,x,y,radius, color):
super().__init__()
self.x = x
self.y = y
self.color = color
self.radius = radius
self.vel = vel
self.image = pygame.Surface((self.radius * 2, self.radius * 2), pygame.SRCALPHA)
pygame.draw.circle(self.image, self.color, (self.radius, self.radius), self.radius)
self.rect = self.image.get_rect(center = (self.x, self.y))
class Enemy(pygame.sprite.Sprite):
def __init__(self):
super().__init__()
self.image = pygame.Surface((20,20))
self.image.fill((255, 0, 0))
y = random.randrange (0, 480)
x = 400
self.rect = self.image.get_rect(topleft = (x, y))
self.speed = random.randrange(1,3)
player = Player(x, y, width, height)
enemies = pygame.sprite.Group()
bullets = pygame.sprite.Group()
all_sprites = pygame.sprite.Group()
all_sprites.add(player)
# Main loop
running = True
clock = pygame.time.Clock()
while running:
clock.tick(FPS)
for event in pygame.event.get():
if event.type == pygame.QUIT:
running = False
if event.type == pygame.KEYDOWN:
if event.key == pygame.K_SPACE and len(bullets) < 5:
bullet = B(player.rect.centerx, player.rect.centery, 3, (0,0,0))
bullets.add(bullet)
all_sprites.add(bullet)
if len(enemies) < 8:
e = Enemy()
enemies.add(e)
all_sprites.add(e)
for bullet in bullets:
if bullet.rect.right < 500:
bullet.rect.x += bullet.vel
else:
bullet.kill()
for enemy in enemies:
if enemy.rect.right > 0:
enemy.rect.x -= enemy.speed
else:
enemy.kill()
pygame.sprite.groupcollide(bullets, enemies, True, True)
keys = pygame.key.get_pressed()
if keys[pygame.K_w] and player.rect.top > player.vel:
player.rect.y -= player.vel
if keys[pygame.K_s] and player.rect.bottom < 500 - player.vel:
player.rect.y += player.vel
SCREEN.fill((190, 232, 220))
all_sprites.draw(SCREEN)
pygame.display.update()
pygame.quit()

Per the documentation:
"When subclassing the Sprite, be sure to call the base initializer before adding the Sprite to Groups."
So the first two lines of Enemy __init__() should be:
def __init__(self):
pygame.sprite.Sprite.__init__(self)
You also need to set a rect for the enemy:
self.rect = self.image.get_rect()
self.rect.x = x
self.rect.y = y

Python pygame sprites collision detection. How to define which sprite withing group collided and effect it's attributes by reducing a point

What am trying to do is to create an Arkanoid game, where the bricks have 3 points of strength each and then they die. The issue is that instead of just the particular brick that gets hit, to lose the points, the whole brick_sprite group is loosing the points. And when one suppose to die, all the previous within the list up to that one dies. I think the issue is that it loops considering the update on line #240. Please check line 65 at def collision(self): under Brick Class. The issue is somewhere there.
"""This is a simple version of arkanoid game"""
import sys
import pygame
import random
# Set colors R G B
white = (255, 255, 255)
black = (0, 0, 0)
orange = (255, 100, 10)
light_blue = (0, 144, 255)
shadow = (192, 192, 192)
purple = (152, 0, 152)
# Display
display_height = 999
display_width = 444
pygame.display.set_caption = ("Arkanoid 1.0")
FPS = 60
# Movement speed
speed = display_width // 60
# Movements
left = (-speed, 0)
right = (speed, 0)
up = (0, speed)
diagonal_left = [-speed, -speed]
diagonal_right = [speed, -speed]
# Game objects dimentions
base_dimentions = (display_width // 5, display_height // 100)
[brick_width, brick_height] = [display_width // 20 * 2, display_height // 100]
brick_dimentions = [brick_width, brick_height]
ball_dimentions = (display_height // 100, display_height // 100)
# Initializing text font
pygame.font.init()
txt_font = pygame.font.SysFont("Score: ", display_height//44)
# Initializing sprite lists
all_sprites = pygame.sprite.Group()
brick_sprites = pygame.sprite.Group()
class Brick(pygame.sprite.Sprite):
def __init__(self, point_value, center):
pygame.sprite.Sprite.__init__(self)
self.image = pygame.Surface(brick_dimentions)
self.image.fill(purple)
self.rect = self.image.get_rect()
self.rect.center = center
self.point_value = point_value
def update(self):
self.collision()
def collision1(self): #This works no issue.
# If brick is hit, loses a point
collision = pygame.sprite.spritecollide(ball, brick_sprites, True)
return collision
def collision(self): #Here is the issue.
# If brick is hit, loses a point
collision = pygame.sprite.spritecollide(ball, brick_sprites, False)
if collision:
self.point_value -= 1
if self.point_value == 0:
self.kill() ## BUGGISH ##"""
class Ball(pygame.sprite.Sprite):
"""Initiates a moving ball and its' attributes"""
def __init__(self):
pygame.sprite.Sprite.__init__(self)
self.image = pygame.Surface(ball_dimentions)
self.image.fill(light_blue)
self.rect = self.image.get_rect()
self.rect.center = self.init_position()
self.direction = random.choice([diagonal_left, diagonal_right])
self.score = 0
def update(self):
self.movement()
def init_position(self):
# Initialize position of the ball
init_position = (board.rect.center[0],
(board.rect.center[1] - (base_dimentions[1] / 2)
- (ball_dimentions[1] / 2)))
return init_position
def collision(self):
# If hit bricks
collision = pygame.sprite.spritecollideany(ball, brick_sprites)
if collision:
self.direction[1] *= -1
self.score += 1
enter code here
def movement(self):
self.containment()
self.rect[1] += self.direction[1]
self.rect[0] += self.direction[0]
self.deflect()
self.ball_loss()
self.collision()
def containment(self):
if self.rect.right >= display_width or self.rect.left <= 0:
self.direction[0] *= -1
if self.rect.top <= 0:
self.direction[1] *= -1
def ball_loss(self):
if self.rect.bottom >= display_height:
self.reset()
bricks_reset()
def reset(self):
self.rect.center = self.init_position()
self.direction[1] *= -1
self.score = 0
def deflect(self):
# If hit base_board, deflect
if (self.rect.bottom == board.rect.top and
(board.rect.left <= self.rect.left <= board.rect.right or
board.rect.left <= self.rect.right <= board.rect.right)):
self.direction[1] *= -1
self.board_ball_interaction()
def board_ball_interaction(self):
# When board is moving, effects balls direction/speed
keystate = pygame.key.get_pressed()
if keystate[pygame.K_LEFT] and board.rect.left > 0:
self.direction[0] -= speed // 2
elif keystate[pygame.K_RIGHT] and board.rect.right < display_width:
self.direction[0] += speed // 2
class Base_board(pygame.sprite.Sprite):
"""Initiates base_board class and it's attributes"""
def __init__(self):
pygame.sprite.Sprite.__init__(self)
self.image = pygame.Surface(base_dimentions)
self.image.fill(orange)
self.rect = self.image.get_rect()
self.rect.center = (display_width // 2,
display_height - 2 * base_dimentions[1])
self.x_direction = 0
def update(self):
# Up-dates classes' position according to user's imput
self.x_direction = 0
self.movement()
self.rect.x += self.x_direction
def movement(self):
# Creates movement and constrains object within screen dimentions
keystate = pygame.key.get_pressed()
if keystate[pygame.K_LEFT]:
if not self.rect.left <= 0:
self.x_direction = -speed
elif keystate[pygame.K_RIGHT]:
if not self.rect.right >= display_width:
self.x_direction = speed
def shoot(self):
pass
def enlogate(self):
pass
def control():
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit()
sys.exit()
# and adding all sprites on lists
board = Base_board()
ball = Ball()
all_sprites.add(board)
all_sprites.add(ball)
def bricks_list_creator():
# Creates and adds bricks into a list
i = 9
point_value = 2 ####
coordinates = [display_width // 20 + brick_width / 6, display_height // 20]
while i > 0:
brick = Brick(point_value, (coordinates)) ####
coordinates[0] += brick_width * 1.1
brick_sprites.add(brick)
i -= 1
return brick_sprites
def bricks_reset():
# Reset brick list
brick_sprites.empty()
bricks_list_creator()
return brick_sprites
def render_text(screen):
text = txt_font.render("Score: {0}".format(ball.score), 1, (0, 0, 0))
return screen.blit(text, (5, 10))
def render_main(screen):
all_sprites.draw(screen)
brick_sprites.draw(screen)
render_text(screen)
# Game main
def main():
pygame.init()
clock = pygame.time.Clock()
screen = pygame.display.set_mode((display_width, display_height))
bricks_list_creator()
while True:
# Events
clock.tick(FPS)
control()
# Update
brick_sprites.update()
all_sprites.update()
# Render
screen.fill(shadow)
render_main(screen)
pygame.display.flip()
pygame.display.update()
main()

I think the issue is in the update() of your Brick class calling the collision.
The sprite update function is typically used for changing the position or look of your sprite, and is called every frame. So it's not a good place to check for collisions.
A Brick only needs to know its point_value, it doesn't move (AFAIK).
class Brick(pygame.sprite.Sprite):
def __init__(self, point_value, center):
pygame.sprite.Sprite.__init__(self)
self.image = pygame.Surface(brick_dimentions)
self.image.fill(purple)
self.rect = self.image.get_rect()
self.rect.center = center
self.point_value = point_value
def takeHit( self, ball_sprite ):
# the ball has collided with *this* brick
self.point_value -= 1
if self.point_value == 0:
self.kill()
Then in Ball.collision() use the pygame.sprite.spritecollide() to get the list of Bricks the Ball has collided with, and reduce their hit points:
class Ball:
# [...]
def collision(self):
# calculate the list of bricks hit
hit_list = pygame.sprite.spritecollide( self, brick_sprites, False )
for brick in hit_list:
brick.takeHit() # may (or may not) kill the brick
Most of the time the hit_list is going to be a single Brick, but depending on the size of the ball, perhaps occasionally it's two bricks.

Space Invaders - Pygame - Random Shoot

I am making the game Space Invaders in Pygame and I want to let the enemy shoot randomly at the player. At this moment I can only let the enemy shoot at the player by pressing the tab button. But it should do this automatically and with a random interval. How can I get this working, without needing to press tab?
Thanks.
import pygame, sys
from pygame.locals import *
import random
screenWidth = 800
screenHeight = 600
FPS = 60
pygame.init()
pygame.mixer.init()
screen = pygame.display.set_mode((screenWidth,screenHeight))
pygame.display.set_caption("Space Invaders")
clock = pygame.time.Clock()
shipWidth = 67
#colors
black=(0,0,0)
blue=(0,0, 255)
green=(0,128,0)
red=(255,0,0)
white=(255,255,255)
yellow=(255,255,0)
def app_quit():
pygame.quit()
sys.exit("System exit.")
class Player(pygame.sprite.Sprite):
def __init__(self):
pygame.sprite.Sprite.__init__(self)
self.image = pygame.image.load("spaceship3.png").convert()
self.image.set_colorkey(white)
self.rect = self.image.get_rect()
self.rect.centerx = screenWidth / 2
self.rect.bottom = screenHeight - 10
def update(self):
self.speedx = 0
if event.type == KEYDOWN and event.key == K_LEFT:
self.speedx = -2
elif event.type == KEYDOWN and event.key == K_RIGHT:
self.speedx = 2
self.rect.x += self.speedx
if self.rect.right > screenWidth:
self.rect.right = screenWidth
if self.rect.left < 0:
self.rect.left = 0
def shootPlayer(self):
bulletPlayer = BulletPlayer(self.rect.centerx, self.rect.top)
allSprites.add(bulletPlayer)
bulletsPlayer.add(bulletPlayer)
class Enemy(pygame.sprite.Sprite):
def __init__(self):
pygame.sprite.Sprite.__init__(self)
self.image = pygame.image.load("enemy.png").convert()
self.image.set_colorkey(white)
self.rect = self.image.get_rect()
self.rect.x = 0
self.rect.y = random.randrange(0, 200)
self.speedx = random.randrange(1, 2)
def update(self):
self.rect.x += self.speedx
if self.rect.right > screenWidth:
self.rect.x = 0
self.rect.y = random.randrange(0, 250)
self.speedx = random.randrange(1, 3)
# if self.rect.x > screenWidth: #kill when of the screen
# self.kill()
def shootEnemy(self):
bulletEnemy = BulletEnemy(self.rect.centerx, self.rect.bottom)
allSprites.add(bulletEnemy)
bulletsEnemy.add(bulletEnemy)
class BulletPlayer(pygame.sprite.Sprite):
def __init__(self, x, y):
pygame.sprite.Sprite.__init__(self)
self.image = pygame.image.load("bullet.png").convert()
self.image.set_colorkey(white)
self.rect = self.image.get_rect()
self.rect.bottom = y
self.rect.centerx = x
self.speedy = -3
def update(self):
self.rect.y += self.speedy
if self.rect.bottom < 0:
self.kill()
class BulletEnemy(pygame.sprite.Sprite):
def __init__(self, x, y):
pygame.sprite.Sprite.__init__(self)
self.image = pygame.image.load("bulletenemy.png").convert()
self.image.set_colorkey(white)
self.rect = self.image.get_rect()
self.rect.bottom = y
self.rect.centerx = x
self.speedy = 2
def update(self):
self.rect.y += self.speedy
if self.rect.bottom > screenHeight:
self.kill()
class Wall(pygame.sprite.Sprite):
def __init__(self):
pygame.sprite.Sprite.__init__(self)
self.image = pygame.image.load("wall.png").convert()
self.rect = self.image.get_rect()
self.rect.center = 100, 300
allSprites = pygame.sprite.Group()
player = Player()
enemy = pygame.sprite.Group()
bulletsPlayer = pygame.sprite.Group()
bulletsEnemy = pygame.sprite.Group()
wall = Wall()
allSprites.add(player, enemy, bulletsPlayer, bulletsEnemy, wall)
for i in range(1):
e = Enemy()
allSprites.add(e)
enemy.add(e)
running = True
while True:
for event in pygame.event.get():
if event.type == QUIT or (event.type == KEYUP and event.key == K_ESCAPE):
running = False
app_quit()
elif event.type == pygame.KEYDOWN:
if event.key == pygame.K_SPACE:
player.shootPlayer()
if event.key == pygame.K_TAB:
random.choice(enemy.sprites()).shootEnemy()
allSprites.update()
hitplayer = pygame.sprite.spritecollide(player, bulletsEnemy, True)
if hitplayer:
running = app_quit()
hitenemy = pygame.sprite.groupcollide(enemy, bulletsPlayer, True, True)
if hitenemy:
running = app_quit()
screen.fill(black)
allSprites.draw(screen)
pygame.display.flip()
pygame.quit()

You need a random timer variable which you can decrement by the dt (delta time) each frame. When it's below zero, create a bullet instance, add it to the group and reset the timer. I use the random.uniform function here which gives you a float, but you could also use random.randrange or randint if you want ints. To get the delta time (the time since the last tick) just assign the value that clock.tick(fps) returns to a variable.
# The timer is the time in seconds until the enemy shoots.
timer = random.uniform(2, 6) # Random float between 2 and 6.
dt = 0
running = True
while True:
# Event handling omitted.
# Decrease the timer by the delta time.
timer -= dt
if timer <= 0: # Ready to fire.
# Pick a random enemy to get the x and y coords.
random_enemy = random.choice(enemy.sprites())
enemy_x, enemy_y = random_enemy.rect.center
# Create a bullet and add it to the sprite groups.
bullet = BulletEnemy(enemy_x, enemy_y)
allSprites.add(bullet)
enemy.add(bullet)
timer = random.uniform(2, 6) # Reset the timer.
# Collision detection and drawing omitted.
# clock.tick returns the time that has passed since the last frame.
dt = clock.tick(60) / 1000 # / 1000 to convert it to seconds.

One way to do it is to create a custom event and trigger it based off some conditions, such as time.
You can use pygame.event.Event() and pygame.event.post() to trigger an event manually instead of using the Tab key. To setup this event on time you can use pygame.time.set_timer(myEvent, time). After that your main loop just needs to check for the event with pygame.event.get().
There is a good example of how to use custom events in pygame here: PyGame Custom Event
The author's example is even a Space Invaders type game so it will be useful to look at how it is written.

Python (pygame) collision detection - sprite and group

I am new to python and am trying to write a game that launches a character and when he interacts with a sprite on the ground, something will change, for example speed. My apologies for the disorganization in my code. I have taken samples from a few tutorials and I can't make them work together.
How do I make the player's collision with the bomb detectable?
import pygame
import random
import math
drag = 1
gravity = (math.pi, .4)
elasticity = .75
# Colors
BLACK = ( 0, 0, 0)
WHITE = ( 255, 255, 255)
BLUE = ( 0, 0, 255)
RED = ( 255, 0, 0)
GREEN = ( 0, 255, 0)
# Screen dimensions
SCREEN_WIDTH = 800
SCREEN_HEIGHT = 600
def addVectors((angle1, length1), (angle2, length2)):
x = math.sin(angle1) * length1 + math.sin(angle2) * length2
y = math.cos(angle1) * length1 + math.cos(angle2) * length2
angle = 0.5 * math.pi - math.atan2(y, x)
length = math.hypot(x, y)
return (angle, length)
class Player(pygame.sprite.Sprite):
change_x = 0
change_y = 0
level = None
def __init__(self, x, y):
pygame.sprite.Sprite.__init__(self)
self.image = pygame.image.load('player.png')
image_rect = self.image.get_rect()
self.rect = pygame.rect.Rect(x, y, image_rect.width, image_rect.height)
def update(self):
pass
def move(self):
(self.angle, self.speed) = addVectors((self.angle, self.speed), gravity)
self.rect.x += math.sin(self.angle) * self.speed
self.rect.y -= math.cos(self.angle) * self.speed
self.speed *= drag
def bounce(self):
if self.rect.x > 800 - self.rect.width:
self.rect.x = 2*(800 - self.rect.width) - self.rect.x
self.angle = - self.angle
self.speed *= elasticity
elif self.rect.x < 0:
self.rect.x = 2*self.rect.width - self.rect.x
self.angle = - self.angle
self.speed *= elasticity
if self.rect.y > SCREEN_HEIGHT - self.rect.height:
self.rect.y = 2*(SCREEN_HEIGHT - self.rect.height) - self.rect.y
self.angle = math.pi - self.angle
self.speed *= elasticity
class Bomb(pygame.sprite.Sprite):
def __init__(self, x, y):
pygame.sprite.Sprite.__init__(self)
self.image = pygame.image.load('cherry.png')
image_rect = self.image.get_rect()
self.rect = pygame.rect.Rect(x, y, image_rect.width, image_rect.height)
class Level():
bomb_list = None
world_shift = 0
def __init__(self, player):
self.bomb_list = pygame.sprite.Group()
self.player = player
def update(self):
self.bomb_list.update()
def draw(self, screen):
screen.fill(BLACK)
self.bomb_list.draw(screen)
def shift_world(self, shift_x):
self.world_shift += shift_x
for bomb in self.bomb_list:
bomb.rect.x += shift_x
if bomb.rect.x < 0:
self.bomb_list.remove(bomb)
self.bomb_list.add(Bomb(random.randint(SCREEN_WIDTH, 2*SCREEN_WIDTH), 580))
I am not sure if this Level_01 class is even necessary:
class Level_01(Level):
def __init__(self, player):
Level.__init__(self, player)
bombs = 0
for n in range(10):
self.bomb_list.add(Bomb(random.randint(0, SCREEN_WIDTH), 580))
This was my attempt at a collision detection method. I'm not sure if it should be in a class, in main, or seperate. I can't seem to get the list of bombs, and the player at the same time.
def detectCollisions(sprite1, sprite_group):
if pygame.sprite.spritecollideany(sprite1, sprite_group):
sprite_group.remove(pygame.sprite.spritecollideany(sprite1, sprite_group))
print True
else:
print False
def main():
pygame.init()
size = [SCREEN_WIDTH, SCREEN_HEIGHT]
screen = pygame.display.set_mode(size)
active_sprite_list = pygame.sprite.Group()
enemy_list = pygame.sprite.Group()
player = Player(0, 0)
player.speed = 30
player.angle = math.radians(45)
player.rect.x = 500
player.rect.y = SCREEN_HEIGHT - player.rect.height
active_sprite_list.add(player)
done = False
clock = pygame.time.Clock()
current_level = Level_01(player)
while not done:
for event in pygame.event.get():
if event.type == pygame.QUIT:
done = True
if event.type == pygame.KEYDOWN:
if event.key == pygame.K_LEFT:
player.go_left()
if event.key == pygame.K_RIGHT:
player.go_right()
active_sprite_list.update()
enemy_list.update()
player.level = current_level
player.move()
player.bounce()
if player.rect.x >= 500:
diff = player.rect.x - 500
player.rect.x = 500
current_level.shift_world(-diff)
if player.rect.x <= 120:
diff = 120 - player.rect.x
player.rect.x = 120
current_level.shift_world(diff)
current_level.draw(screen)
active_sprite_list.draw(screen)
enemy_list.draw(screen)
clock.tick(60)
pygame.display.flip()
pygame.quit()
if __name__ == "__main__":
main()
Thanks for helping me out!

Probably the easiest thing to do is to draw out pixels (or virtual pixels) and if in drawing bomb/person pixels you find an overlap then you know a collision occurred.
You can however get way more complicated (and efficient) in your collision detection if you need a higher performance solution. See Wikipedia Collision Detection for a reference.

I suggest creating sprite groups using pygame.sprite.Group() for each class; Bomb and Player. Then, use pygame.sprite.spritecollide().
For example:
def Main()
...
player_list = pygame.sprite.Group()
bomb_list = pygame.sprite.Group()
...
Then in your logic handling loop, after creating a Player and Bomb instance, you could do something like this:
for bomb in bomb_list:
# See if the bombs has collided with the player.
bomb_hit_list = pygame.sprite.spritecollide(bomb, player_list, True)
# For each bomb hit, remove bomb
for bomb in bomb_hit_list:
bomb_list.remove(bomb)
# --- Put code here that will trigger with each collision ---