所以我有这段代码,它可以正常工作。我想要它做的是按不同的数量随机缩放正方形,它确实这样做了。我的问题在于 blit 函数,我的正方形似乎只是按比例放大,因为 blit 不会删除旧形状,它只是将新形状复制到表面。
如何使形状扩大和缩小,而不仅仅是扩大?
我的代码:
import sys, random, pygame
from pygame.locals import *
pygame.init()
w = 640
h = 480
screen = pygame.display.set_mode((w,h))
morphingShape = pygame.Surface((20,20))
morphingShape.fill((255, 137, 0)) #random colour for testing
morphingRect = morphingShape.get_rect()
def ShapeSizeChange(shape, screen):
x = random.randint(-21, 20)
w = shape.get_width()
h = shape.get_height()
if w + x > 0 and h + x > 0:
shape = pygame.transform.smoothscale(shape, (w + x, h + x))
else:
shape = pygame.transform.smoothscale(shape, (w - x, h - x))
shape.fill((255, 137, 0))
rect = shape.get_rect()
screen.blit(shape, rect)
return shape
while True:
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit()
sys.exit()
morphingShape = ShapeSizeChange(morphingShape, screen)
pygame.display.update()
最佳答案
在每一帧(While 循环的每次迭代)你都应该删除屏幕。默认情况下,屏幕(窗口)颜色为黑色,因此您应该通过调用 screen.fill( (0,0,0) )
清除屏幕。下面是完整的代码,现在可以正常工作了:
import sys, random, pygame
from pygame.locals import *
pygame.init()
w = 640
h = 480
screen = pygame.display.set_mode((w,h))
morphingShape = pygame.Surface((20,20))
morphingShape.fill((255, 137, 0)) #random colour for testing
morphingRect = morphingShape.get_rect()
# clock object that will be used to make the animation
# have the same speed on all machines regardless
# of the actual machine speed.
clock = pygame.time.Clock()
def ShapeSizeChange(shape, screen):
x = random.randint(-21, 20)
w = shape.get_width()
h = shape.get_height()
if w + x > 0 and h + x > 0:
shape = pygame.transform.smoothscale(shape, (w + x, h + x))
else:
shape = pygame.transform.smoothscale(shape, (w - x, h - x))
shape.fill((255, 137, 0))
rect = shape.get_rect()
screen.blit(shape, rect)
return shape
while True:
# limit the demo to 50 frames per second
clock.tick( 50 );
# clear screen with black color
# THIS IS WHAT WAS REALLY MISSING...
screen.fill( (0,0,0) )
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit()
sys.exit()
morphingShape = ShapeSizeChange(morphingShape, screen)
pygame.display.update()
请注意,只需添加 screen.fill( (0,0,0) )
即可解决您的问题。
关于python - Pygame,如何在屏幕上绘制形状并删除之前的表面?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/11767236/