@@ -121,18 +121,19 @@ def use(self) -> None:
         cache's the window viewport to determine the projection matrix.
         """
 
+        viewport = self.viewport.viewport
         # If the viewport is correct and the default camera is in use,
         # then don't waste time resetting the view and projection matrices
-        if self._ctx.viewport == self.viewport.viewport and self._ctx.current_camera == self:
+        if self._ctx.viewport == viewport and self._ctx.current_camera == self:
             return
 
         # If the viewport has changed while the default camera is active then the
         # default needs to update itself.
         # If it was another camera's viewport being used the default camera should not update.
-        if self._ctx.viewport != self.viewport and self._ctx.current_camera == self:
+        if self._ctx.viewport != viewport and self._ctx.current_camera == self:
             self.viewport = LBWH(*self._ctx.viewport)
         else:
-            self._ctx.viewport = self.viewport.viewport
+            self._ctx.viewport = viewport
 
         self._ctx.current_camera = self