circle.cpp

class Circle {
  // Várias coisas...
  HDC drawing;
  MakeDrawing(HDC hdc) {
    CreateCompatibleDC(hdc);
    Ellipse(hdc, /*Args...*/);
  }
  Paint(HDC hdc) {
    SelectObject(hdc, drawing);
    BitBlt(hdc, /*Args...*/, SRCCOPY);
  }
};