feat(branding): 更换应用图标与开屏资源

tools/generate_brand_assets.py

@@ -12,7 +12,7 @@ IOS = ROOT / "ios/Runner/Assets.xcassets"
 ANDROID = ROOT / "android/app/src/main/res"
 REFERENCE = ROOT / "assets/branding/ymb-reference.png"
 LAUNCH_REFERENCE = ROOT / "assets/branding/ymb-launch-reference.png"
-BRAND_RED = "#E9142E"
+BRAND_BACKGROUND = "#000000"
 WHITE = "#FFFFFF"
 CLEAR = (0, 0, 0, 0)
 MASTER_SIZE = 1024
@@ -104,7 +104,7 @@ def android_assets(master, foreground):
             ANDROID / f"drawable-{density}/ic_launcher_foreground.png",
         )
         save(
-            Image.new("RGB", (pixels, pixels), BRAND_RED),
+            Image.new("RGB", (pixels, pixels), BRAND_BACKGROUND),
             ANDROID / f"mipmap-{density}/ic_launcher_background.png",
         )
         mark = splash_icon(master, round(SPLASH_SIZE * scale))
@@ -117,10 +117,13 @@ def android_assets(master, foreground):
 def main():
     """直接复用确认的原始图标和开屏，输出平台所需尺寸。"""
     reference = Image.open(REFERENCE).convert("RGB")
-    master = reference.resize((MASTER_SIZE, MASTER_SIZE), RESAMPLE)
     mark = wordmark(reference)
+    master = centered(
+        Image.new("RGBA", (MASTER_SIZE, MASTER_SIZE), (0, 0, 0, 255)),
+        mark.resize((MASTER_SIZE, MASTER_SIZE), RESAMPLE),
+    )
     foreground = mark.resize((MASTER_SIZE, MASTER_SIZE), RESAMPLE)
-    save(master, ASSETS / "ymb.png")
+    save(master.convert("RGB"), ASSETS / "ymb.png")
     save(foreground, ASSETS / "ymb_foreground.png")
     placeholder = centered(
         Image.new("RGBA", PLACEHOLDER_SIZE, CLEAR),