Svelte Transitions

Written — Updated
  • Useful Transitions
    • Slide in from the side
      • function horzSlideTransition(node, { duration }) {
          return {
            css: (t) => {
         // This always slides in from the right.
         const eased = 1 - cubicOut(t);
         return `transform: translateX(${eased * 100}%)`;
  • Deferred Transitions
    • These can be useful for more advanced cases.
    • They feel complicated, but basically your transition function does some initialization and then returns another function.
      • Svelte will call that function only once all other elements starting a transition at the same time have run their initialization.
      • This lets you set up some shared state between multiple transitioning elements.
        • Important caveat: Elements that are transitioning but not in the same component may not always transition on the same tick.
    • crossfade is the deferred transition that comes with the Svelte library.
    • svelte-zoomable uses these extensively to coordinate multiple elements.

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