Question

I’m a beginner programmer and my first language is Python 2.7, I’m trying to make a space invader type game but i want to have multiple bullets at once and cant find a way to do that. so i made my own way here is my code ill explain more after you see it

        if event.type ==pygame.KEYDOWN and event.key==K_SPACE:
            if m < 5:
                m+=1

            if m==1:
                m1a=1
                m1x=ls

            if m==2:
                m2a=1
                m2x=ls

            if m==3:
                m3a=1
                m3x=ls

            if m==4:
                m4a=1
                m4x=ls

            if m==5:
                m5a=1
                m5x=ls

            print m
#missle 1
    if m1a==1:
        screen.blit(rship,(m1x,m1))
        if m1>=0:
            m1-=1
        else:
            m-=1
            m1a=0
            m1=460
#missle 2
    if m2a==1:
        screen.blit(rship,(m2x,m2))
        if m2>=0:
            m2-=1
        else:
            m-=1
            m2a=0
            m2=460
#missle 3
    if m3a==1:
        screen.blit(rship,(m3x,m3))
        if m3>=0:
            m3-=1
        else:
            m-=1
            m3a=0
            m3=460
#missle 4
    if m4a==1:
        screen.blit(rship,(m4x,m4))
        if m4>=0:
            m4-=1
        else:
            m-=1
            m4a=0
            m4=460
#missle 5
    if m5a==1:
        screen.blit(rship,(m5x,m5))
        if m5>=0:
            m5-=1
        else:
            m-=1
            m5a=0
            m5=460

I’m sure its laughably noobish but I’m just learning but the problem is the first and second missile are fine its the third and beyond that get messed up. when you fire the third it moves the second over the where your shooting from and then if you fir again the code wont go back down to 1 it stays at 2 and gets even more glitches. If you need me to try and explain it better I gladly will. Just trying to Learn.

Full code here: pastebin.com/FnPaME6N

Answer 1

Here is some working code, but I wouldn’t call it great.

import pygame
import math
from pygame.locals import *
background_colour = (122, 100, 155)
(width, height) = (500, 500)

pygame.init()

#ship = pygame.image.load('lolol.jpeg')\
rship = pygame.image.load('js.jpg')
mis = pygame.image.load('lot.jpg')
screen = pygame.display.set_mode((width, height))
pygame.display.set_caption('A.N.T.O.N.I.A.')
screen.fill(background_colour)
pygame.display.flip()
running = True

MAX_MISSILES = 5

ls = 250  # Horizontal ship location

LEFT = False
RIGHT = False

def move(ls, RIGHT, LEFT):
    '''Moves the ship 3 pixels to the left or right.

    Only moves if just one direction key is down, and not both.
    Also, will not move if the ship is at either horizontal screen edge.

    ls is the ship location.

    '''
    if LEFT and not RIGHT:
        if ls >= 10:
            ls -= 3
    elif RIGHT and not LEFT:
        if ls <= 440:
            ls += 3
    return ls

def fire_missile(ls, missiles):
    '''Fire a missile, as long as we are not at the maximum number.

    We use a list to hold our missile locations.

    '''
    if len(missiles) >= MAX_MISSILES:
        return
    else:
        missiles.append((ls, 460))

def draw_missiles(missiles):
    '''Draw all the missiles.'''
    if missiles:
        for missile in missiles:
            screen.blit(mis, (missile))

def move_missiles(missiles):
    '''If there are any missiles, move them up 1 pixel, and append
    them to the newlist.  The new list will replace the old list.

    '''
    if missiles:
        newmissiles = []
        for missile in missiles:
            # Do not append the missile to the new list if it is going
            # off the screen
            if missile[1] > 0:
                newmissiles.append((missile[0], missile[1] - 1))
        return newmissiles
    else:
        return missiles

missiles = []

while running:
    screen.blit(rship, (ls, 450))
    pygame.display.flip()
    screen.fill(background_colour)
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            running = False
        if event.type == pygame.KEYDOWN and event.key == K_ESCAPE:
            # You can now quit with the escape key.
            pygame.quit()
            running = False
        if event.type == pygame.KEYDOWN and event.key == K_LEFT:
            LEFT = True
        # LEFT is True untli you let up in the LEFT key
        if event.type == pygame.KEYUP and event.key == K_LEFT:
            LEFT = False
        if event.type == pygame.KEYDOWN and event.key == K_RIGHT:
            RIGHT = True
        if event.type == pygame.KEYUP and event.key == K_RIGHT:
            RIGHT = False
        if event.type == pygame.KEYDOWN and event.key == K_SPACE:
            fire_missile(ls, missiles)
    ls = move(ls, RIGHT, LEFT)
    draw_missiles(missiles)
    missiles = move_missiles(missiles)

Any time you find yourself making variables with numbers in them, it’s a code smell, and means you probably should use a different data type.

As has been suggested, you’ll probably want to look into the sprite and group modules, but this will at least do what you were trying to do so far.