[PyGame] Getting projectiles into pygame.

[Everett_]

Hey all,

I'm really new to Python, this is only really my 5th or 6th day using the language (or really any major language). When I was younger I used Scratch a lot so if I'm using the wrong terminology or I am being unclear I'm sorry I can clear things up if you would like me to:).

Right now this I'm trying to create a space-invaders-type clone, this is my first project without the direct help of a guide. So I want to have bullets come out of my plane sprite. I'm trying to figure out how to do two things really, one is to get a 'clone' of the bullet sprite to spawn at an x and y relative to the plane. I know how to use .blit((x, y)) but I can't figure out how to get a clone of the sprite to spawn in so I can have multiple bullets coming out of the plane. The next thing I want to figure out is how to get that new spawned clone of the sprite to keep going towards y = 0 and stopping either when it gets there or collides with the enemy(ies)

I've googled some guides and posts and I either can't figure out how it could apply to my project or I can't understand what is happening. I saw a lot of ideas including classes and lists and while I understand what lists are I don't see/understand how they apply here, I am also starting to understand the usefulness of classes but they still are a bit confusing to me.
Thanks for any help:)

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# imports and initializations import pygame import random pygame.init()       # game start   running = True     gametick = 100 px = 250 # player x and y py = 275 pvel = 25 # player velocity and bullet vel bvel = 40 mod = 1 clock = pygame.time.Clock()   # window window_height = 600 window_width = 800 window = pygame.display.set_mode((window_width, window_height)) pygame.display.set_caption("Game")     # sprite imports. playerImg = pygame.image.load("images\player.png") backgroundImg = pygame.image.load("images\Background.png") bulletImg = pygame.image.load("images\Bullet.png")         # Definitions   def player(px, py):     window.blit(playerImg, (px, py))     pygame.transform.scale(playerImg, (10, 10))     def background():     window.blit(backgroundImg, (0, 0))     def borders():     global px     if px <= 0:         px = 0     elif px >= 704:         px = 704       # Gameloop while running:       clock.tick(30)     # Stop command     for event in pygame.event.get():         if event.type == pygame.QUIT:             running = False     # Showing sprites and background     background()     player(px, py)     # bullets     # nothing here yet       # Controls     keys = pygame.key.get_pressed()     if keys[pygame.K_LEFT]:         borders()         px -= pvel * mod     if keys[pygame.K_RIGHT]:         borders()         px += pvel * mod     if keys[pygame.K_UP]:         pass # this will be for the bullets         pygame.display.update()

[michael1789]

The short answer is to use the Pygame Sprite Class.

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class Player(pygame.sprite.Sprite):     def __init__(self):         pygame.sprite.Sprite.__init__(self)         self.image = pygame.transform.scale(player_img, (60, 48))         self.image.set_colorkey(black)         self.rect = self.image.get_rect()         self.radius = 25         self.rect.center = (width / 2, height - 30)         self.speedx = 0         self.shield = 100         self.shoot_delay = 250         self.last_shot = pygame.time.get_ticks()         self.lives = 1         self.hidden = False         self.hide_timer = pygame.time.get_ticks()         self.power = 1         self.power_time = pygame.time.get_ticks()                         def update(self):                   if self.power >= 2 and pygame.time.get_ticks() - self.power_time > POWERUP_TIME:             self.power -= 1             self.power_time = pygame.time.get_ticks()                       if self.hidden and pygame.time.get_ticks() - self.hide_timer > 1000:             self.hidden = False             self.rect.center = (width / 2, height - 30)         self.speedx = 0         keystate = pygame.key.get_pressed()         self.rect.x += self.speedx         if keystate[pygame.K_LEFT]:             self.speedx = -10         if keystate[pygame.K_RIGHT]:             self.speedx = 10                   if keystate[pygame.K_SPACE]:             self.shoot()         self.rect.x += self.speedx         if self.rect.right > width:             self.rect.right = width         if self.rect.left < 0:             self.rect.left = 0           def powerup(self):         self.power += 1                   self.power_time = pygame.time.get_ticks()               def shoot(self):         now = pygame.time.get_ticks()         if now - self.last_shot > self.shoot_delay:             self.last_shot = now             if self.power == 1:                 bullet = Bullet(self.rect.centerx, self.rect.top)                 all_sprites.add(bullet)                 bullets.add(bullet)                 shoot_sound.play()             if self.power >= 2:                 bullet1 = Bullet(self.rect.left, self.rect.centery)                 bullet2 = Bullet(self.rect.right, self.rect.centery)                 all_sprites.add(bullet1)                 bullets.add(bullet1)                 all_sprites.add(bullet2)                 bullets.add(bullet2)                 shoot_sound.play()            def hide(self):         self.hidden = True         self.hide_timer = pygame.time.get_ticks()         self.rect.center = (width / 2, height + 200)              class Bullet(pygame.sprite.Sprite):     def __init__(self, x, y):         pygame.sprite.Sprite.__init__(self)         self.image = bullet_img         self.image.set_colorkey(black)         self.rect = self.image.get_rect()         self.rect.bottom = y         self.rect.centerx = x         self.speedy = -50                         def update(self):         self.rect.y += self.speedy                             if self.rect.bottom < 0:             self.kill()

This is cut from a vertical shooter I made from a tutorial. Specifically Player.shoot() refers to what you ask.

A great video about classes can be seen here.

[Windspar]

For now just use classes as container. There two level to a class. Class level for a single instance. Objects for multiply instances. Class is a namespace you use to access variables.

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player_x = 250 player_y = 270 player_velocity = 25

You could just use a class level instance. Only one instance can be made this way.

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class Player:     x = 250     y = 275     velocity = 25 # To access variable of class instance. You use the namespace print(Player.x) print(Player.y) print(Player.velocity)

If you wanted many different players. Then you use class object instances.

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class Player:     # Class object initializer     def __init__(self, x, y, velocity):         self.x = x         self.y = y         self.velocity = velocity   # Create a player. Argument match the __init__ method. player_a = Player(250, 270, 25) # Now player_a point to are new player class object. # player_a will be are namespace to the object. print(player_a.x)   # Create are second player player_b = Player(450, 470, 25) print(player_a.x) print(player_b.x)

What does self mean in a class. It standard word that point to your object. Uses self.x create a variable x in your object.

Bullets. Use a list to store bullets positions. Only need list if shooting more than on bullet.

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bullets = [] bullets_remover = [] bullet_next_tick = 0 bullet_interval = 100 # how fast it can shoot

Use pygame.time.get_ticks() to control bullet shooting speed.

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ticks = pygame.time.get_ticks() if keys[pygame.K_UP]:     if ticks > bullet_next_tick:         bullet_next_tick = ticks + bullet_interval         bullets.append([px, py])   for bullet in bullets:     # Move bullet     bullet[1] -= 5     if bullet[y] < 0:         bullet_remover.append(bullet)     else:         window.blit(bulletImg, bullet)   for bullet in bullet_remover:     bullets.remove(bullet)   bullet_remover = []

[lolloiltizio]

Wow I'm new in this forum but I love it, i had same problem since I got used to scratch clones... Thank you!
Here my first try with pygame.

[Everett_]

Thank you all this is really helpful! :)

[lolloiltizio]

Hey boys, I've successfully created a space invaders clone with pygame thanks to you!

I've used the "list method" and if you want to use a Rect instead an Img with windows.blit, you have to write the for loop after the pygame.draw(things) like this (note I've used some variables like colors that are not declared!):

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screen.fill(bgcolor) pygame.draw.rect(screen, color, ship)   for bullet in bullets:     bullet.y -= 5     if bullet.y < 0:         bullet_remover.append(bullet)     else:         pygame.draw.rect(screen, color, bullet pygame.display.flip() clock.tick(60)

Put this after the whole thing
This is the code for the bullets, but with enemies is the same.
To CONTROL the bullet shoot, you can simply append a Rect to the list in the while loop like this:

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while True:     ticks = pygame.time.get_ticks()     for event in pygame.event.get():           if event.type == pygame.QUIT:             pygame.mixer.music.stop()             pygame.quit()             print('Thanks for playing Space invaders! \nclosing...')             sys.exit()           if event.type == pygame.KEYDOWN:               if event.key == pygame.K_UP:                 if ticks > bullet_next_tick:                     bullet_next_tick = ticks + bullet_interval                     bullets.append(pygame.Rect(ship.x, ship.y, 5, 20))               if event.key == pygame.K_RIGHT:                 x_spid += 5               if event.key == pygame.K_LEFT:                 x_spid -= 5           if event.type == pygame.KEYUP:               if event.key == pygame.K_RIGHT:                 x_spid -= 5               if event.key == pygame.K_LEFT:                 x_spid += 5

Obviously you still need to remove bullets

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for bullet in bullet_remover:     bullets.remove(bullet)   bullet_remover = []

I'm really happy and proud of that. Thank you. Relly, thank you.
(Tell me if you'd like to see the project ;))

---

Hey boys, I've successfully created a space invaders clone with pygame thanks to you!

I've used the "list method" and if you want to use a Rect instead an Img with windows.blit, you have to write the for loop after the pygame.draw(things) like this (note I've used some variables like colors that are not declared!):

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screen.fill(bgcolor) pygame.draw.rect(screen, color, ship)   for bullet in bullets:     bullet.y -= 5     if bullet.y < 0:         bullet_remover.append(bullet)     else:         pygame.draw.rect(screen, color, bullet pygame.display.flip() clock.tick(60)

Put this after the whole thing
This is the code for the bullets, but with enemies is the same.
To CONTROL the bullet shoot, you can simply append a Rect to the list in the while loop like this:

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while True:     ticks = pygame.time.get_ticks()     for event in pygame.event.get():           if event.type == pygame.QUIT:             pygame.mixer.music.stop()             pygame.quit()             print('Thanks for playing Space invaders! \nclosing...')             sys.exit()           if event.type == pygame.KEYDOWN:               if event.key == pygame.K_UP:                 if ticks > bullet_next_tick:                     bullet_next_tick = ticks + bullet_interval                     bullets.append(pygame.Rect(ship.x, ship.y, 5, 20))               if event.key == pygame.K_RIGHT:                 x_spid += 5               if event.key == pygame.K_LEFT:                 x_spid -= 5           if event.type == pygame.KEYUP:               if event.key == pygame.K_RIGHT:                 x_spid -= 5               if event.key == pygame.K_LEFT:                 x_spid += 5

Obviously you still need to remove bullets

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for bullet in bullet_remover:     bullets.remove(bullet)   bullet_remover = []

I'm really happy and proud of that. Thank you. Relly, thank you.
(Tell me if you'd like to see the project ;))

*really