ui(raylib): calculcate spinner progress in update

The spinner logic was refactored to calculate the progress or text ahead of time
in the `set_text` method, instead of checking `text.isdigit()` in every render
iteration. This change improves performance by avoiding unnecessary checks in
the render loop. The lock is used when reading `_progress` and `_text` to avoid
race conditions.

system/ui/spinner.py

@@ -26,11 +26,17 @@ class Spinner:
     self._spinner_texture = gui_app.load_texture_from_image(os.path.join(BASEDIR, "selfdrive/assets/img_spinner_track.png"), TEXTURE_SIZE, TEXTURE_SIZE)
     self._rotation = 0.0
     self._text: str = ""
+    self._progress: int | None = None
     self._lock = threading.Lock()
 
   def set_text(self, text: str) -> None:
     with self._lock:
-      self._text = text
+      if text.isdigit():
+        self._progress = clamp(int(text), 0, 100)
+        self._text = ""
+      else:
+        self._progress = None
+        self._text = text
 
   def render(self):
     center = rl.Vector2(gui_app.width / 2.0, gui_app.height / 2.0)
@@ -49,23 +55,21 @@ class Spinner:
     rl.draw_texture_v(self._comma_texture, comma_position, rl.WHITE)
 
     # Display progress bar or text based on user input
-    text = None
+    y_pos = rl.get_screen_height() - MARGIN - PROGRESS_BAR_HEIGHT
     with self._lock:
+      progress = self._progress
       text = self._text
 
-    if text:
-      y_pos = rl.get_screen_height() - MARGIN - PROGRESS_BAR_HEIGHT
-      if text.isdigit():
-        progress = clamp(int(text), 0, 100)
-        bar = rl.Rectangle(center.x - PROGRESS_BAR_WIDTH / 2.0, y_pos, PROGRESS_BAR_WIDTH, PROGRESS_BAR_HEIGHT)
-        rl.draw_rectangle_rounded(bar, 1, 10, DARKGRAY)
+    if progress is not None:
+      bar = rl.Rectangle(center.x - PROGRESS_BAR_WIDTH / 2.0, y_pos, PROGRESS_BAR_WIDTH, PROGRESS_BAR_HEIGHT)
+      rl.draw_rectangle_rounded(bar, 1, 10, DARKGRAY)
 
-        bar.width *= progress / 100.0
-        rl.draw_rectangle_rounded(bar, 1, 10, rl.WHITE)
-      else:
-        text_size = rl.measure_text_ex(gui_app.font(), text, FONT_SIZE, 1.0)
-        rl.draw_text_ex(gui_app.font(), text,
-                        rl.Vector2(center.x - text_size.x / 2, y_pos), FONT_SIZE, 1.0, rl.WHITE)
+      bar.width *= progress / 100.0
+      rl.draw_rectangle_rounded(bar, 1, 10, rl.WHITE)
+    elif text:
+      text_size = rl.measure_text_ex(gui_app.font(), text, FONT_SIZE, 1.0)
+      rl.draw_text_ex(gui_app.font(), text,
+                      rl.Vector2(center.x - text_size.x / 2, y_pos), FONT_SIZE, 1.0, rl.WHITE)
 
 
 if __name__ == "__main__":