How to Implement a Cooldown Mechanism to Prevent Excessive Bullet Firing?

How to Prevent Multiple Bullet Firing Simultaneously

In the original code, multiple bullets were being fired at once due to the fact that the pygame.key.get_pressed() function returns True for as long as a key is pressed down. This behavior is suitable for controlling player movement but not for firing bullets, where you want only one bullet to be fired each time a key is pressed.

To fix this issue, we can take advantage of the pygame.KEYDOWN event, which occurs only once when a key is initially pressed. By using this event instead of pygame.key.get_pressed(), we can ensure that only one bullet is fired when the spacebar is pressed.

Additionally, we can implement a simple cooldown mechanism to prevent rapid-fire bullet shooting. This can be done by introducing a variable called next_bullet_threshold, which represents the earliest time that the next bullet can be fired. Each time a bullet is fired, we update next_bullet_threshold to the current time plus the desired cooldown period. By checking if the current time is greater than next_bullet_threshold, we can prevent any bullets from being fired outside of the desired cooldown period.

Here is the modified code with the implemented cooldown mechanism:

<code class="python">import pygame
pygame.init()

red = 255,0,0
blue = 0,0,255
black = 0,0,0

screenWidth = 800
screenHeight = 600

gameDisplay = pygame.display.set_mode((screenWidth,screenHeight))        ## screen width and height
pygame.display.set_caption('JUST SOME BLOCKS')       ## set my title of the window

clock = pygame.time.Clock()

class player():       ## has all of my attributes for player 1
    def __init__(self,x,y,width,height):
        self.x = x
        self.y = y
        self.height = height
        self.width = width
        self.vel = 5
        self.left = False
        self.right = False
        self.up = False
        self.down = False

class projectile():     ## projectile attributes
    def __init__(self,x,y,radius,colour,facing):
        self.x = x
        self.y = y
        self.radius = radius
        self.facing = facing
        self.colour = colour
        self.vel = 8 * facing       # speed of bullet * the direction (-1 or 1)

    def draw(self,gameDisplay):
        pygame.draw.circle(gameDisplay, self.colour , (self.x,self.y),self.radius)      ## put a 1 after that to make it so the circle is just an outline

def redrawGameWindow():
    for bullet in bullets:      ## draw bullets
        bullet.draw(gameDisplay)

    pygame.display.update()   

#mainloop

player1 = player(300,410,50,70)     # moves the stuff from the class (when variables are user use player1.var)
bullets = []

run = True
next_bullet_threshold = 0  # Initialize the cooldown threshold
bullet_cooldown = 500  # Set the desired cooldown period in milliseconds
while run == True:
    clock.tick(27)
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            run = False

    for bullet in bullets:
        if bullet.x < screenWidth and bullet.x > 0 and bullet.y < screenHeight and bullet.y > 0: ## makes sure bullet does not go off screen
            bullet.x += bullet.vel
        else:
            bullets.pop(bullets.index(bullet))


    keys = pygame.key.get_pressed()     ## check if a key has been pressed

    ## red player movement   
    if keys[pygame.K_w] and player1.y > player1.vel:    ## check if that key has been pressed down (this will check for w)     and checks for boundry
        player1.y -= player1.vel            ## move the shape in a direction
        player1.up = True
        player1.down = False

    if keys[pygame.K_a] and player1.x > player1.vel:      ### this is for a 
        player1.x -= player1.vel
        player1.left = True
        player1.right = False

    if keys[pygame.K_s] and player1.y < screenHeight - player1.height - player1.vel: ## this is for s
        player1.y += player1.vel
        player1.down = True
        player1.up = False

    if keys[pygame.K_d] and player1.x < screenWidth - player1.width - player1.vel:   ## this is for d                          
        player1.x += player1.vel
        player1.right = True
        player1.left = False

    if keys[pygame.K_SPACE]:     # shooting with the space bar
        current_time = pygame.time.get_ticks()
        if current_time >= next_bullet_threshold:  # Check the cooldown timer
            if player1.left == True:   ## handles the direction of the bullet
                facing = -1
            else:
                facing = 1  

            if len(bullets) < 5:    ## max amounts of bullets on screen
                bullets.append(projectile(player1.x + player1.width //2 ,player1.y + player1.height//2,6,black,facing))   ##just like calling upon a function
                next_bullet_threshold = current_time + bullet_cooldown  # Update cooldown timer


    ## level


    gameDisplay.fill((0,255,0))        ### will stop the shape from spreading around and will have a background
    pygame.draw.rect(gameDisplay,(red),(player1.x,player1.y,player1.width,player1.height))  ## draw player
    pygame.display.update()
    redrawGameWindow()

pygame.quit()</code>

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