Pygame 仅在第二次运行程序时闪烁

Question

我有一个我编写的简单的 pygame 程序，我正在使用 raspberry pi lite OS (buster) 在 raspberry pi CM4 上运行。 因此我不得不手动安装 x 以便 pygame 可以输出一些东西。 这是使用以下命令完成的：

sudo apt-get install --no-install-recommends xserver-xorg xinit x11-xserver-utils openbox

我在启动时通过在 my.bash_profile 中包含以下内容来启动程序：

[[ -z $DISPLAY && $XDG_VTNR -eq 1 ]] && startx -- -nocursor

以及/etc/xdg/openbox/autostart中的这段代码：

# Disable any form of screen saver / screen blanking / power management
xset s off
xset s noblank
xset -dpms

# Allow quitting the X server with CTRL-ATL-Backspace
setxkbmap -option terminate:ctrl_alt_bksp

cd project_dir && python project.py

这是 project_dir/project.py 的内容：

import pygame as pg

class Game:
    def __init__(self):
        pg.init()

        self.__clock = pg.time.Clock()

        self.__window_size = (1024, 768)
        self.__project_size = (392, 291)

        self.screen = pg.display.set_mode(self.__window_size, pg.FULLSCREEN)

        self.blank_background = pg.transform.scale(pg.image.load("assets/default_background.png"),
                self.__window_size).convert()
        self.grid_image = pg.transform.scale(pg.image.load("assets/new_project_thumb.png"),
                self.__project_size).convert()

        self.project_selected = 0

        self.rect_pixels = 3

        self.grid_locations = self.calculate_grid_locations()

    def run(self) -> None:
        pg.mouse.set_visible(False)

        playing = True

        while playing:
            events = pg.event.get()

            button_event = None

            self.screen.blit(self.blank_background, (0, 0))

            for event in events:
                if event.type == pg.KEYDOWN:
                    button_event = event.key

            if button_event == pg.K_LEFT:
                self.project_selected = max((self.project_selected - 1), 0)

            if button_event == pg.K_RIGHT:
                self.project_selected = min((self.project_selected + 1), 3)

            if button_event == pg.K_ESCAPE:
                playing = False

            self.draw_menu()
            pg.display.update()
            self.__clock.tick(6)

    def draw_menu(self):
        for i in range(4):
            if i == self.project_selected:
                rect_loc = (self.grid_locations[i][0] - self.rect_pixels,
                            self.grid_locations[i][1] - self.rect_pixels)
                pg.draw.rect(self.screen,
                             (237, 28, 36),
                             pg.Rect(rect_loc,
                                     (self.__project_size[0] + self.rect_pixels * 2,
                                      self.__project_size[1] + self.rect_pixels * 2)))

            self.screen.blit(self.grid_image, self.grid_locations[i])
                                                        

    def calculate_grid_locations(self):
        w=int((self.__window_size[0] - 2 * self.__project_size[0]) / 3)
        h=int((self.__window_size[1] - 2 * self.__project_size[1]) / 3)

        return [(w, h),
                (w * 2 + self.__project_size[0], h),
                (w, h * 2 + self.__project_size[1]),
                (w * 2 + self.__project_size[0], h * 2 + self.__project_size[1])]

if __name__ == "__main__":
    game = Game()
    game.run()

该程序在自动启动时运行良好，但如果我在使用 ctrl-alt-backspace 自动启动后退出程序和 x，然后使用python project.py从命令行重新启动它，则显示会在 pygame 程序的帧之间间歇性闪烁。 在我的 ubuntu 笔记本电脑上运行时不会发生这种情况，只是在 CM4 上。

有谁知道这可能是什么原因造成的？

Answer 1

想通了 - 问题是我正在杀死 x 服务器。 如果 x 服务器被杀死，Python / pygame 仍然可以以某种方式输出到屏幕，但性能确实下降了。 如果我再次运行startx -- -nocursor而不是python project.py ，它会再次启动 x server 并在/etc/xdg/openbox/autostart中运行整个脚本作为启动的一部分，这也会导致程序启动.