asclass Animation {
  int w = 128, h = 128;
  double fps = 20;
  Graphics2D g;
  
  *() {}
  *(int *w, int *h) {}
  
  void setSize(int w, int h) {
    this.w = w;
    this.h = h;
  }
  
  void setGraphics(Graphics2D g) {
    this.g = g;
  }
  
  // override me
  void start {}
  
  // override me
  void paint {}
  
  // override me
  void nextFrame {}
  
  BufferedImage toImage() {
    var img = whiteImage(w, h);
    setGraphics(createGraphics(img));
    paint();
    ret img;
  }
}

Began life as a copy of #1033723