Function overlay

src/styles/overlay.tsx:11–29

(
  elevation: T,
  surfaceColor: string = MD2DarkTheme.colors?.surface
)

): it is Animated.Value => it instanceof Animated.Value;

export default function overlay<T extends Animated.Value | number>(
  elevation: T,
  surfaceColor: string = MD2DarkTheme.colors?.surface
): T extends number ? string : Animated.AnimatedInterpolation<number | string> {
  if (isAnimatedValue(elevation)) {
    const inputRange = [0, 1, 2, 3, 8, 24];

    // @ts-expect-error: TS doesn't seem to refine the type correctly
    return elevation.interpolate({
      inputRange,
      outputRange: inputRange.map((elevation) => {
        return calculateColor(surfaceColor, elevation);
      }),
    });
  }

  // @ts-expect-error: TS doesn't seem to refine the type correctly
  return calculateColor(surfaceColor, elevation);
}

function calculateColor(surfaceColor: string, elevation: number = 1) {
  let overlayTransparency: number;