There are two types of scroll animations:

• Scroll-triggered: A normal animation is triggered when an element enters the viewport.

• Scroll-linked: Values are linked directly to scroll progress.

Motion is capable of both types of animation.

Scroll-triggered animations

Scroll-triggered animations are just normal animations that fire when an element enters or leaves the viewport.

Motion offers the whileInView prop to set an animation target or variant when the element enters the view.

<motion.div
  initial={{ opacity: 0 }}
  whileInView={{ opacity: 1 }}
/>

One-time animations

With the viewport options, it's possible to set once: true so once an element has entered the viewport, it won't animate back out.

<motion.div
  initial="hidden"
  whileInView="visible"
  viewport={{ once: true }}
/>

Changing scroll container

By default, the element will be considered within the viewport when it enters/leaves the window. This can be changed by providing the ref of another scrollable element.

function Component() {
  const scrollRef = useRef(null)
  
  return (
    <div ref={scrollRef} style={{ overflow: "scroll" }}>
      <motion.div
        initial={{ opacity: 0 }}
        whileInView={{ opacity: 1 }}
        viewport={{ root: scrollRef }}
      />
    </div>
  )
}

For more configuration options, checkout the motion component API reference.

Setting state

It's also possible to set state when any element (not just a motion component) enters and leaves the viewport with the useInView hook.

Scroll-linked animations

Scroll-linked animations are created using motion values and the useScroll hook.

useScroll returns four motion values, two that store scroll offset in pixels (scrollX and scrollY) and two that store scroll progress as a value between 0 and 1.

These motion values can be passed directly to specific styles. For instance, passing scrollYProgress to scaleX works great as a progress bar.

const { scrollYProgress } = useScroll();

return (
  <motion.div style={{ scaleX: scrollYProgress }} />  
)

Since scrollY is a MotionValue, there's a neat trick you can use to tell when the user's scroll direction changes:

const { scrollY } = useScroll()
const [scrollDirection, setScrollDirection] = useState("down")

useMotionValueEvent(scrollY, "change", (current) => {
  const diff = current - scrollY.getPrevious()
  setScrollDirection(diff > 0 ? "down" : "up")
})

Perfect for triggering a sticky header animation!
~ Sam Selikoff, Motion for React Recipes

Value smoothing

This value can be smoothed by passing it through useSpring.

const { scrollYProgress } = useScroll();
const scaleX = useSpring(scrollYProgress, {
  stiffness: 100,
  damping: 30,
  restDelta: 0.001
})

return <motion.div style={{ scaleX }} />

Transform other values

With the useTransform hook, it's easy to use the progress motion values to mix between any value, like colors:

const backgroundColor = useTransform(
  scrollYProgress,
  [0, 0.5, 1],
  ["#f00", "#0f0", "#00f"]
)

return <motion.div style={{ backgroundColor }} />

Examples

Change scroll container

Track element position

Parallax

3D

Scroll velocity and direction

Read the full useScroll docs to discover more about creating the above effects.