Pygame 使用时钟的延迟问题
Pygame Latency Issue using clock
我用 pygame 制作了一个贪吃蛇游戏，运行良好。但是，有时它对用户输入的响应不是很好。我正在使用时钟和延迟来设置蛇移动的速度。
移动代码：
pygame.time.delay(1)
clock.tick(7)
player.move()
render_screen()
渲染屏幕：
screen.fill((0, 0, 0))
draw_grid()
player.draw()
food.draw()
screen.fill((0, 0, 0), (0, 513, 512, 50))
start.draw()
screen.blit(comic_font.render('Score: ' + str(score), False, (255, 100, 0)), (10, size + 5))
pygame.display.update()
完整代码：
import pygame
import random
pygame.init()
class Snake:
def __init__(self, x, y):
self.x = x
self.y = y
self.speed_x = 1
self.speed_y = 0
segments = []
for a in range(1, 4):
segments.append(Segment(self.x - a, self.y))
self.segments = segments
def move(self):
global score, game_mode
# handle key inputs
keys = pygame.key.get_pressed()
for key in keys:
if self.speed_x == 0:
if keys[pygame.K_a]:
self.speed_x = -1
self.speed_y = 0
if keys[pygame.K_d]:
self.speed_x = 1
self.speed_y = 0
elif self.speed_y == 0:
if keys[pygame.K_w]:
self.speed_x = 0
self.speed_y = -1
if keys[pygame.K_s]:
self.speed_x = 0
self.speed_y = 1
# check for wall collisions
if self.x + self.speed_x < 0 or self.x + self.speed_x > rows - 1 or self.y + self.speed_y > rows - 1 or \
self.y + self.speed_y < 0:
game_mode = "end"
start.text = "RETRY"
return None
# moves snake
self.segments.insert(0, Segment(self.x, self.y))
self.x += self.speed_x
self.y += self.speed_y
# checks for self collisions
for segment in self.segments:
if self.x == segment.x and self.y == segment.y and self.segments.index(segment)!=len(self.segments)-1:
game_mode = "end"
start.text = "RETRY"
break
# checks for eating food
if self.x == food.x and self.y == food.y:
food.x = random.randrange(0, 16)
food.y = random.randrange(0, 16)
score += 1
else:
self.segments.pop()
def draw(self):
for segment in self.segments:
segment.draw()
pygame.draw.rect(screen, (255, 0, 0), (self.x * size / rows, self.y * size / rows, size / rows, size / rows))
class Segment:
def __init__(self, x, y):
self.x = x
self.y = y
def draw(self):
pygame.draw.rect(screen, (0, 255 - player.segments.index(self), 0),
(self.x * size / rows, self.y * size / rows, size / rows, size / rows))
class Food:
def __init__(self, x, y):
self.x = x
self.y = y
def draw(self):
pygame.draw.rect(screen, (255, 255, 0), (self.x * size / rows, self.y * size / rows, size / rows, size / rows))
class button:
def __init__(self, x, y, r, g, b, text, font, width, height):
self.x = x
self.y = y
self.r = r
self.b = b
self.g = g
self.text = text
self.font = font
self.width = width
self.height = height
def draw(self):
pygame.draw.rect(screen, (self.r, self.g, self.b), (self.x, self.y, self.width, self.height))
screen.blit(self.font.render(self.text, False, (0, 100, 0)), (self.x + 10, self.y))
def mouse_over(self, pos):
if self.x < pos[0] < self.x + self.width and self.y < pos[1] < self.y + self.height:
return True
def draw_grid():
margin = size / rows
x = 0
y = 0
for line in range(rows):
x = x + margin
y = y + margin
pygame.draw.line(screen, (255, 255, 255), (x, 0), (x, size))
pygame.draw.line(screen, (255, 255, 255), (0, y), (size, y))
def render_screen():
screen.fill((0, 0, 0))
draw_grid()
player.draw()
food.draw()
screen.fill((0, 0, 0), (0, 513, 512, 50))
start.draw()
screen.blit(comic_font.render('Score: ' + str(score), False, (255, 100, 0)), (10, size + 5))
pygame.display.update()
size = 512
rows = 16
screen = pygame.display.set_mode((size, size + 50))
pygame.display.set_caption("Snake")
comic_font = pygame.font.SysFont("Comic Sans MS", 30)
clock = pygame.time.Clock()
running = True
game_mode = "wait"
player = Snake(8, 8)
food = Food(random.randrange(0, 16), random.randrange(0, 16))
start = button(size - 155, size + 5, 0, 255, 0, "PLAY", comic_font, 150, 40)
score = 0
render_screen()
while running:
for event in pygame.event.get():
pos = pygame.mouse.get_pos()
if event.type == pygame.QUIT:
running = False
elif event.type == pygame.MOUSEBUTTONDOWN:
if start.mouse_over(pos):
if game_mode == "wait":
game_mode = "play"
start.text = "PAUSE"
elif game_mode == "play":
game_mode = "wait"
start.text = "RESUME"
elif game_mode == "end":
game_mode = "play"
start.text = "PAUSE"
score = 0
running = True
game_mode = "wait"
player = Snake(8, 8)
food = Food(random.randrange(0, 16), random.randrange(0, 16))
render_screen()
if game_mode == "play":
pygame.time.delay(1)
clock.tick(7)
player.move()
render_screen()
上面是重现问题的完整代码。
稍微试验了一下，好像pygame.time.delay(1)越小，延迟越小。
我认为用户在抽动之间只能读取输入，因此他们必须在现场准确输入。
我想也许这就是为什么当延迟较小时输入不落后的原因，因为延迟会影响每个输入之间的时长。
有谁知道为什么游戏在某些时候不能很好地接收输入？
pygame.key.get_pressed() returns 一个列表，包含所有键盘按钮的状态。遍历此列表没有意义，因为您只想评估键的当前状态 was d.
根据按下的键设置速度：
class Snake:
# [...]
def move(self):
# [...]
# handle key inputs
keys = pygame.key.get_pressed()
if self.speed_x == 0:
if keys[pygame.K_a]:
self.speed_x, self.speed_y = -1, 0
elif keys[pygame.K_d]:
self.speed_x, self.speed_y = 1, 0
elif self.speed_y == 0:
if keys[pygame.K_w]:
self.speed_x, self.speed_y = 0, -1
elif keys[pygame.K_s]:
self.speed_x, self.speed_y = 0, 1
# [...]
pygame.time.Clock.tick 延迟以使游戏 运行 慢于给定的每秒滴答数。 pygame.key.get_pressed() 返回的状态在处理事件时进行评估 (pygame.event.get())。
延迟游戏，等事件处理完毕，蛇被移动，显示更新：
while running:
for event in pygame.event.get():
# [...]
if game_mode == "play":
player.move()
render_screen()
clock.tick(7) # <---
我用 pygame 制作了一个贪吃蛇游戏，运行良好。但是，有时它对用户输入的响应不是很好。我正在使用时钟和延迟来设置蛇移动的速度。
移动代码：
pygame.time.delay(1)
clock.tick(7)
player.move()
render_screen()
渲染屏幕：
screen.fill((0, 0, 0))
draw_grid()
player.draw()
food.draw()
screen.fill((0, 0, 0), (0, 513, 512, 50))
start.draw()
screen.blit(comic_font.render('Score: ' + str(score), False, (255, 100, 0)), (10, size + 5))
pygame.display.update()
完整代码：
import pygame
import random
pygame.init()
class Snake:
def __init__(self, x, y):
self.x = x
self.y = y
self.speed_x = 1
self.speed_y = 0
segments = []
for a in range(1, 4):
segments.append(Segment(self.x - a, self.y))
self.segments = segments
def move(self):
global score, game_mode
# handle key inputs
keys = pygame.key.get_pressed()
for key in keys:
if self.speed_x == 0:
if keys[pygame.K_a]:
self.speed_x = -1
self.speed_y = 0
if keys[pygame.K_d]:
self.speed_x = 1
self.speed_y = 0
elif self.speed_y == 0:
if keys[pygame.K_w]:
self.speed_x = 0
self.speed_y = -1
if keys[pygame.K_s]:
self.speed_x = 0
self.speed_y = 1
# check for wall collisions
if self.x + self.speed_x < 0 or self.x + self.speed_x > rows - 1 or self.y + self.speed_y > rows - 1 or \
self.y + self.speed_y < 0:
game_mode = "end"
start.text = "RETRY"
return None
# moves snake
self.segments.insert(0, Segment(self.x, self.y))
self.x += self.speed_x
self.y += self.speed_y
# checks for self collisions
for segment in self.segments:
if self.x == segment.x and self.y == segment.y and self.segments.index(segment)!=len(self.segments)-1:
game_mode = "end"
start.text = "RETRY"
break
# checks for eating food
if self.x == food.x and self.y == food.y:
food.x = random.randrange(0, 16)
food.y = random.randrange(0, 16)
score += 1
else:
self.segments.pop()
def draw(self):
for segment in self.segments:
segment.draw()
pygame.draw.rect(screen, (255, 0, 0), (self.x * size / rows, self.y * size / rows, size / rows, size / rows))
class Segment:
def __init__(self, x, y):
self.x = x
self.y = y
def draw(self):
pygame.draw.rect(screen, (0, 255 - player.segments.index(self), 0),
(self.x * size / rows, self.y * size / rows, size / rows, size / rows))
class Food:
def __init__(self, x, y):
self.x = x
self.y = y
def draw(self):
pygame.draw.rect(screen, (255, 255, 0), (self.x * size / rows, self.y * size / rows, size / rows, size / rows))
class button:
def __init__(self, x, y, r, g, b, text, font, width, height):
self.x = x
self.y = y
self.r = r
self.b = b
self.g = g
self.text = text
self.font = font
self.width = width
self.height = height
def draw(self):
pygame.draw.rect(screen, (self.r, self.g, self.b), (self.x, self.y, self.width, self.height))
screen.blit(self.font.render(self.text, False, (0, 100, 0)), (self.x + 10, self.y))
def mouse_over(self, pos):
if self.x < pos[0] < self.x + self.width and self.y < pos[1] < self.y + self.height:
return True
def draw_grid():
margin = size / rows
x = 0
y = 0
for line in range(rows):
x = x + margin
y = y + margin
pygame.draw.line(screen, (255, 255, 255), (x, 0), (x, size))
pygame.draw.line(screen, (255, 255, 255), (0, y), (size, y))
def render_screen():
screen.fill((0, 0, 0))
draw_grid()
player.draw()
food.draw()
screen.fill((0, 0, 0), (0, 513, 512, 50))
start.draw()
screen.blit(comic_font.render('Score: ' + str(score), False, (255, 100, 0)), (10, size + 5))
pygame.display.update()
size = 512
rows = 16
screen = pygame.display.set_mode((size, size + 50))
pygame.display.set_caption("Snake")
comic_font = pygame.font.SysFont("Comic Sans MS", 30)
clock = pygame.time.Clock()
running = True
game_mode = "wait"
player = Snake(8, 8)
food = Food(random.randrange(0, 16), random.randrange(0, 16))
start = button(size - 155, size + 5, 0, 255, 0, "PLAY", comic_font, 150, 40)
score = 0
render_screen()
while running:
for event in pygame.event.get():
pos = pygame.mouse.get_pos()
if event.type == pygame.QUIT:
running = False
elif event.type == pygame.MOUSEBUTTONDOWN:
if start.mouse_over(pos):
if game_mode == "wait":
game_mode = "play"
start.text = "PAUSE"
elif game_mode == "play":
game_mode = "wait"
start.text = "RESUME"
elif game_mode == "end":
game_mode = "play"
start.text = "PAUSE"
score = 0
running = True
game_mode = "wait"
player = Snake(8, 8)
food = Food(random.randrange(0, 16), random.randrange(0, 16))
render_screen()
if game_mode == "play":
pygame.time.delay(1)
clock.tick(7)
player.move()
render_screen()
上面是重现问题的完整代码。
稍微试验了一下，好像pygame.time.delay(1)越小，延迟越小。
我认为用户在抽动之间只能读取输入，因此他们必须在现场准确输入。
我想也许这就是为什么当延迟较小时输入不落后的原因，因为延迟会影响每个输入之间的时长。
有谁知道为什么游戏在某些时候不能很好地接收输入？
pygame.key.get_pressed() returns 一个列表，包含所有键盘按钮的状态。遍历此列表没有意义，因为您只想评估键的当前状态 was d.
根据按下的键设置速度：
class Snake:
# [...]
def move(self):
# [...]
# handle key inputs
keys = pygame.key.get_pressed()
if self.speed_x == 0:
if keys[pygame.K_a]:
self.speed_x, self.speed_y = -1, 0
elif keys[pygame.K_d]:
self.speed_x, self.speed_y = 1, 0
elif self.speed_y == 0:
if keys[pygame.K_w]:
self.speed_x, self.speed_y = 0, -1
elif keys[pygame.K_s]:
self.speed_x, self.speed_y = 0, 1
# [...]
pygame.time.Clock.tick 延迟以使游戏 运行 慢于给定的每秒滴答数。 pygame.key.get_pressed() 返回的状态在处理事件时进行评估 (pygame.event.get())。
延迟游戏，等事件处理完毕，蛇被移动，显示更新：
while running:
for event in pygame.event.get():
# [...]
if game_mode == "play":
player.move()
render_screen()
clock.tick(7) # <---