Progress Tracking and Previews?

[JacobCZ]

Would it be possible to implement a way to track generation progress and get previews? Ideally in the form of passable callback functions?

e.g.

def progress_callback(progress: int):
  log.info(f'Generation progress: {progress}%')

def preview_callback(preview: PIL.Image.Image):
  fake_ui.setImage(preview)

# ...

output = generate_txt2img("A tree", progress_callback=progress, preview_callback=preview)