问题
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
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
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
## 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()
When I shoot more than 1 bullet fires and I only want 1 bullet to fire at a time (but not only 1 bullet on the screen)
They all fire in a large clump and stick together also so I want them to fire at different times
I have tried using a delay clock.tick but that makes the game extremely laggy
I am relatively new to pygame and don't fully understand it any help would be appreciated thanks !
回答1:
The states which are returned by pygame.key.get_pressed() are, set, as long a key is hold down. That is useful for the movement of a player. The player keeps moving as long a key is hold down.
But it contradicts your intention, when you want to fire a bullet. If you want to fire a bullet when a key is pressed, then can use the KEYDOWN event. The event occurs only once when a key is pressed:
while run == True:
clock.tick(27)
for event in pygame.event.get():
if event.type == pygame.QUIT:
run = False
if event.type == pygame.KEYDOWN:
if event.key == pygame.K_SPACE:
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
bx, by = player1.x + player1.width //2 ,player1.y + player1.height//2
bullets.append(projectile(bx, by, 6, black, facing))
# [...]
If you want to implement some kind of rapid fire, then the things get more tricky. If you would use the state of pygame.key.get_pressed() then you would spawn one bullet in every frame. That is far too fast. You have to implement some timeout.
When a bullet is fired, the get the current time by pygame.time.get_ticks(). Define a number of milliseconds for the delay between to bullets. Add the dela to the time and state the time in a variable (next_bullet_threshold). Skip bullets, as long the time is not exceeded:
next_bullet_threshold = 0
run = True
while run == True:
# [...]
current_time = pygame.time.get_ticks()
if keys[pygame.K_SPACE] and current_time > next_bullet_threshold:
bullet_delay = 500 # 500 milliseconds (0.5 seconds)
next_bullet_threshold = current_time + bullet_delay
if player1.left == True: ## handles the direction of the bullet
facing = -1
else:
facing = 1
if len(bullets) < 5:
bx, by = player1.x + player1.width //2 ,player1.y + player1.height//2
bullets.append(projectile(bx, by, 6, black, facing))
Minimal example: repl.it/@Rabbid76/PyGame-ShootBullet
import pygame
pygame.init()
window = pygame.display.set_mode((500, 200))
clock = pygame.time.Clock()
tank_surf = pygame.Surface((60, 40), pygame.SRCALPHA)
pygame.draw.rect(tank_surf, (0, 96, 0), (0, 00, 50, 40))
pygame.draw.rect(tank_surf, (0, 128, 0), (10, 10, 30, 20))
pygame.draw.rect(tank_surf, (32, 32, 96), (20, 16, 40, 8))
tank_rect = tank_surf.get_rect(midleft = (20, window.get_height() // 2))
bullet_surf = pygame.Surface((10, 10), pygame.SRCALPHA)
pygame.draw.circle(bullet_surf, (64, 64, 62), bullet_surf.get_rect().center, bullet_surf.get_width() // 2)
bullet_list = []
max_bullets = 4
next_bullet_time = 0
bullet_delta_time = 200 # milliseconds
run = True
while run:
clock.tick(60)
current_time = pygame.time.get_ticks()
for event in pygame.event.get():
if event.type == pygame.QUIT:
run = False
if event.type == pygame.KEYDOWN:
if len(bullet_list) < max_bullets and current_time >= next_bullet_time:
next_bullet_time = current_time + bullet_delta_time
bullet_list.insert(0, tank_rect.midright)
for i, bullet_pos in enumerate(bullet_list):
bullet_list[i] = bullet_pos[0] + 5, bullet_pos[1]
if bullet_surf.get_rect(center = bullet_pos).left > window.get_width():
del bullet_list[i:]
break
window.fill((224, 192, 160))
window.blit(tank_surf, tank_rect)
for bullet_pos in bullet_list:
window.blit(bullet_surf, bullet_surf.get_rect(center = bullet_pos))
pygame.display.flip()
pygame.quit()
exit()
来源：https://stackoverflow.com/questions/60122492/how-do-i-stop-more-than-1-bullet-firing-at-once