Question

我想画一段延时的多行。我正在使用for循环来寻找x和y坐标。我正在寻找一种解决方案来绘制这些线之间的时间延迟（例如1秒）。这是我的代码：

import pygame,sys
pygame.init()

screen = pygame.display.set_mode((1600, 900)) 
RED = (230, 30, 30)

background_image = pygame.image.load("image.jpg")
background_image = pygame.transform.scale(background_image, (1600,900))

clock = pygame.time.Clock()

# Main loop
while True:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
                sys.exit()
        # Fill the background
         screen.blit(background_image, [0, 0])
         x= [60,70,80]
         y= [500,600,700]
         for x,y in zip(x,y):
                pygame.draw.line(background_image, RED,(x,y),(900,1280), 10)
                pygame.display.update()
                pygame.time.delay(10)
# Update the screen
        pygame.display.flip()

`

Answer 1

您必须在screen而不是background_image上绘制线条。 500毫秒是半秒（10毫秒是位快）。另外，不要对列表和坐标使用相同的变量名称。

import sys
import pygame


pygame.init()

screen = pygame.display.set_mode((1024, 768)) 
RED = (150, 30, 30)

# Replaced the image with a Surface to test the code.
background_image = pygame.Surface((1024, 768))  
background_image.fill((50, 90, 140))

clock = pygame.time.Clock()
xs = [60, 70, 80, 90]
ys = [500, 600, 700, 800]

while True:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            sys.exit()

    screen.blit(background_image, [0, 0])

    for x, y in zip(xs, ys):
        # Draw the lines on the screen not the background.
        pygame.draw.line(screen, RED, (x, y), (400, 480), 10)
        pygame.display.update()
        pygame.time.delay(500)

    pygame.display.flip()
    clock.tick(30)

此版本仍有问题，因为您停止执行其余主要版本 for循环运行时循环。这意味着您不能在此期间退出或处理其他事件。

我有一个更复杂的例子，你有一个计时器变量。您从它中减去增量时间（自上次刻度后经过的时间），当它低于0时，您将另一个坐标添加到用于绘图的列表中。

import sys
import pygame


pygame.init()

screen = pygame.display.set_mode((1024, 768))
RED = (120, 30, 30)

background_image = pygame.Surface((1024, 768))
background_image.fill((50, 90, 140))

clock = pygame.time.Clock()

xs = [60, 70, 80, 90]
ys = [400, 500, 600, 700]
xys = zip(xs, ys)
startpoints = []  # This holds the current startpoints.

dt = 0
timer = 500  # A countdown timer.

while True:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            sys.exit()

    timer -= dt  # Decrease timer.
    if timer <= 0:  # If timer < 0 append the next xy coords.
        try:
            # `next` just gives you the next item in the xys zip iterator.
            startpoints.append(next(xys))
        # When the zip iterator is exhausted, clear the
        # startpoints list and create a new zip iterator.
        except StopIteration:
            startpoints.clear()
            xys = zip(xs, ys)
        timer = 500  # Reset the timer.

    screen.blit(background_image, [0, 0])
    for x, y in startpoints:  # Loop over the available startpoints.
        pygame.draw.line(screen, RED, (x, y), (400, 480), 10)

    pygame.display.flip()
    dt = clock.tick(30)

或者您可以使用自定义事件和pygame.time.set_timer：

进行相同的操作

add_coord_event = pygame.USEREVENT + 1
pygame.time.set_timer(add_coord_event, 500)

while True:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            sys.exit()
        if event.type == add_coord_event:
            try:
                startpoints.append(next(xys))
            # When the zip iterator is exhausted, clear the
            # startpoints list and create a new zip iterator.
            except StopIteration:
                startpoints.clear()
                xys = zip(xs, ys)

编辑：或者更好的方法是在while循环之前创建起始点列表，并使用i对其进行切片。然后，您不必将项目从迭代器移动到列表。

xs = [60, 70, 80, 90]
ys = [400, 500, 600, 700]
startpoints = list(zip(xs, ys))
i = 0  # Current index, used to slice startpoints.

clock = pygame.time.Clock()
increase_index_event = pygame.USEREVENT + 1
pygame.time.set_timer(increase_index_event, 500)

while True:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            sys.exit()
        if event.type == increase_index_event:
            i += 1
            i %= len(startpoints) + 1  # Keep i in the correct range.

    screen.blit(background_image, [0, 0])
    for x, y in startpoints[:i]:
        pygame.draw.line(screen, RED, (x, y), (500, 580), 10)

    pygame.display.flip()
    clock.tick(30)

Answer 2

您可以使用time.wait()，但这只会冻结您的程序一段时间，或者您可以拥有一个变量来保存该行应该绘制的时间。基本上当你绘制第一行时nextLine = time.clock()+1并在你的循环中有一个if if time.clock > nextLine:然后绘制下一行。

用时间延迟pygame画线

2 个答案: