问题描述
我正在尝试在PyGame中进行外星人入侵，当我type Tuple<T> = readonly T[]
type TuplePick<T,K extends Tuple<keyof T>> = Pick<T,K[number]> // like Pick,but we pass a tuple of the keys
type IfEqualThen<T,U,R> = T extends U ? (U extends T ? R : never) : never // 'R' if T and U are mutually assignable
type AssertAllKeys<P,T extends Tuple<keyof P>> = IfEqualThen<P,TuplePick<P,T>,T>
function assertKeys <P> () {
return function <T extends Tuple<keyof P>> (value: AssertAllKeys<P,T>): T
{
return value
}
}
interface Props {
id: string;
name: string;
age: number;
};
const keys1 = assertKeys<Props>()(['id','name'] as const) // Error,argument not assignable to never
const keys2 = assertKeys<Props>()(['id','name','age'] as const) // Works
宇宙飞船和子弹时，一切工作都顺利进行，但是当我尝试从Sprite组中吸引外星人时，游戏突然停滞了。我已经尝试过使用blit函数，但是即使使用它仍然滞后。
主要：
convert()外星人文件
这是存储外星人的外星人阶级。我已经将图像转换为 .bmp 文件，并且我也尝试使用 import sys
import pygame
from settings import Settings
from ship import Ship
from bullet import Bullet
from alien import Alien
class AlienInvasion:
"""Overall class to manage game assests and behavior"""
def __init__(self):
"""Initialize the game and create resources"""
pygame.init()
self.settings = Settings()
self.screen = pygame.display.set_mode((self.settings.screen_width,self.settings.screen_height))
pygame.display.set_caption("Alien Invasion")
self.ship = Ship(self)
self.bullets = pygame.sprite.Group()
self.aliens = pygame.sprite.Group()
def run_game(self):
"""Start the main loop for the game"""
while True:
clock.tick(60)
self._check_events()
self.ship.update()
self._update_bullets()
self._create_fleet()
self._update_aliens()
self._update_screen()
def _check_events(self):
#watch for keyboard and mouse events
for event in pygame.event.get():
if event.type == pygame.QUIT:
sys.exit()
elif event.type == pygame.KEYDOWN:
self._check_keydown_events(event)
elif event.type == pygame.KEYUP:
self._check_keyup_events(event)
def _check_keydown_events(self,event):
"""Respond to keypress"""
if event.key == pygame.K_RIGHT:
self.ship.moving_right = True
elif event.key == pygame.K_LEFT:
self.ship.moving_left = True
elif event.key == pygame.K_UP:
self.ship.moving_up = True
elif event.key == pygame.K_DOWN:
self.ship.moving_down = True
elif event.key == pygame.K_q:
sys.exit()
elif event.key == pygame.K_SPACE:
self._fire_bullet()
self.ship.firing = True
def _check_keyup_events(self,event):
if event.key == pygame.K_RIGHT:
self.ship.moving_right = False
elif event.key == pygame.K_LEFT:
self.ship.moving_left = False
def _fire_bullet(self):
if len(self.bullets) < self.settings.bullets_allowed:
new_bullet = Bullet(self)
self.bullets.add(new_bullet)
def _update_bullets(self):
self.bullets.update()
#delete bullets
for bullet in self.bullets.copy():
if bullet.rect.bottom <= 0:
self.bullets.remove(bullet)
def _update_aliens(self):
"""Update position of aliens"""
self.aliens.update()
def _create_fleet(self):
alien = Alien(self)
alien_width,alien_height = alien.rect.size
available_space_x = self.settings.screen_width - (2 * alien_width)
number_aliens_x = available_space_x // (2 * alien_width)
#determine number of rows that fit on the screen
ship_height = self.ship.rect.height
available_space_y = self.settings.screen_height - (3*alien_height) - ship_height
number_aliens_y = available_space_y // (2* alien_height)
for row_number in range(number_aliens_y):
for alien_number in range(number_aliens_x):
self._create_alien(alien_number,row_number)
def _create_alien(self,alien_number,row_number):
"""Create alien and place it in a row"""
alien = Alien(self)
alien_width,alien_height = alien.rect.size
alien.x = alien_width + 2 * alien_width * alien_number
alien.rect.y = alien_height + 2 * alien_width * row_number
alien.rect.x = alien.x
self.aliens.add(alien)
def _update_screen(self):
self.screen.fill(self.settings.bg_color)
self.ship.blitme()
for bullet in self.bullets.sprites():
bullet.draw_bullet()
self._create_fleet()
self.aliens.draw(self.screen)
pygame.display.flip()
if __name__ == '__main__':
ai = AlienInvasion()
ai.run_game(
函数，但是它仍然滞后。
convert()解决方法
给我们的问题是，您无法在每帧中创建舰队。因此，新的外星人会在每帧中都添加到 Group 中，并且您绘制的外星人远远超出了必要。更糟糕的是，'images/alien.bmp'被加载到类Alien的构造函数中，因此必须在每一帧中加载多个图像：
class AlienInvasion: # [...] def _update_screen(self): # [...] self._create_fleet() # <---- self.aliens.draw(self.screen)
我建议在构造第一个外星人时将图像一次加载到类变量中：
（请参见Class and Instance Variables）
class Alien(Sprite):
alienimage = None
"""class that represents a single alien in a fleet"""
def __init__(self,ai_game):
# [...]
#load alien image
if self.alienimage == None:
self.alienimage = pygame.image.load('images/alien.bmp').convert()
self.image = self.alienimage
# [...]
在主应用程序循环之前创建车队：
class AlienInvasion:
# [...]
def run_game(self):
self._create_fleet() # <---- ADD
"""Start the main loop for the game"""
while True:
clock.tick(60)
self._check_events()
self.ship.update()
self._update_bullets()
# self._create_fleet() <---- DELETE
self._update_aliens()
self._update_screen()
# [...]
def _update_screen(self):
# [...]
# self._create_fleet() <---- DELETE
self.aliens.draw(self.screen)