Sorry that I have to post here, but there isn't a function to let the picture shake when the screen shakes.
It looks really ugly!
And the problem with the screen tone. Wouldn't it be better to integrate it as an update like this?
def update
@fpm.tone = $game_map.screen.tone
@fpm_viewport.ox = $game_map.screen.shake
But I don't know where to paste it.