Function scaleToFocus

packs/standalone/src/animation.ts:176–196

(
  stepPair: Tuple<Step>,
  dimensions?: Dimensions
)

}

export function scaleToFocus(
  stepPair: Tuple<Step>,
  dimensions?: Dimensions
): Animation<number> {
  if (!dimensions) {
    return () => 1;
  }

  const [prev, next] = stepPair.spread();

  const prevZoom = getZoom(prev, dimensions);
  const nextZoom = getZoom(next, dimensions);

  return t =>
    tween(
      prevZoom || nextZoom!,
      nextZoom || prevZoom!,
      t,
      easing.easeInOutQuad
    );
}

//