data/images/objects/trampoline/trampoline.sprite

(supertux-sprite
  (action
    (name "normal")
    (hitbox 0 0 0 0)
    (images "trampoline1-0.png")
  )
  (action
    (name "swinging")
    (images "trampoline1-0.png"
            "trampoline1-1.png"
            "trampoline1-2.png"
            "trampoline1-3.png")
  )
)