スプライト クラスを作成し、値を update 関数に入れます。このように、配列は関数のスコープ内で作成および破棄されます。スペースバーを押して灰色のブロックを透明にする例を次に示します。
import pygame
from pygame.locals import QUIT, KEYDOWN, K_ESCAPE, K_SPACE, SRCALPHA
class Game(object):
def __init__(self):
pygame.init()
self.width, self.height = 800, 800
pygame.display.set_caption("Surfarray test")
self.screen = pygame.display.set_mode((self.width, self.height))
self.background = pygame.Surface((self.width, self.height))
self.background.fill((255, 255, 255))
self.background.convert()
self.bar = pygame.Surface((200, 100))
self.bar.fill((255, 0, 0))
self.bar.convert()
self.sprite = pygame.sprite.GroupSingle()
self.sprite.add(CustomSprite(pygame.Rect(5, 5, 100, 100)))
def input(self):
for event in pygame.event.get():
if event.type == QUIT:
return False
if event.type == KEYDOWN:
if event.key == K_ESCAPE:
return False
if event.key == K_SPACE:
# make bar transparent by pressing the space bar
self.sprite.update()
def main(self):
while True:
if self.input() is False:
return False
self.draw()
def draw(self):
self.screen.blit(self.background, (0, 0))
self.screen.blit(self.bar, (5, 5))
self.sprite.draw(self.screen)
pygame.display.update()
class CustomSprite(pygame.sprite.Sprite):
def __init__(self, rect):
pygame.sprite.Sprite.__init__(self)
self.rect = rect
# SRCALPHA flag makes the pixel format include per-pixel alpha data
self.image = pygame.Surface((rect.width, rect.height), SRCALPHA)
self.image.convert_alpha()
self.image.fill((126, 126, 126))
# magic happens here
def update(self):
pxa = pygame.surfarray.pixels_alpha(self.image)
pxa[:] = 100 # make all pixels transparent
if __name__ == "__main__":
game = Game()
game.main()