From 5c1fbf80bea05e5c47dbd5e97770210e81276a15 Mon Sep 17 00:00:00 2001
From: 206530407 <1294510428@qq.com>
Date: Tue, 22 Jun 2021 11:38:06 +0800
Subject: [PATCH] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=20'bullet'?=
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---
 bullet | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)
 create mode 100644 bullet

diff --git a/bullet b/bullet
new file mode 100644
index 0000000..25c4685
--- /dev/null
+++ b/bullet
@@ -0,0 +1,32 @@
+import pygame
+from pygame.sprite import Sprite
+
+
+class Bullet(Sprite):
+    """一个对飞船发射的子弹进行管理的类"""
+
+    def __init__(self, ai_settings, screen, ship):
+        """在飞船所处的位置创建一个子弹对象"""
+        super(Bullet, self).__init__()
+        self.screen = screen
+
+        # 在 (0,0) 处创建一个子弹的矩形，再设置正确的位置
+        self.rect = pygame.Rect(0, 0, ai_settings.bullet_width, ai_settings.bullet_height)              #调用Rect类创建子弹矩形
+        self.rect.centerx = ship.rect.centerx               #让子弹矩形的centerx属性等于飞船矩形的centerx属性
+        self.rect.top = ship.rect.top               #让子弹矩形的top属性等于飞船矩形的top属性
+
+        # 存储用小数表示的子弹位置
+        self.y = float(self.rect.y)
+        self.color = ai_settings.bullet_color
+        self.speed_factor = ai_settings.bullet_speed_factor
+
+    def update(self):
+        """向上移动子弹"""
+        # 更新表示子弹位置的小数值
+        self.y -= self.speed_factor
+        # 更新表示子弹的rect的位置
+        self.rect.y = self.y
+
+    def draw_bullet(self):
+        """在屏幕上绘制子弹"""
+        pygame.draw.rect(self.screen, self.color, self.rect)                #调用pygame.draw.rect()绘制子弹矩形到屏幕