Get the spring inversion

[wileyknight]

Is there a way to invert the spring (apply a negative) so that I can spring animate a container that acts as a mask and apply the negative value to a group within to negate the movement so the content appears stationary?

Here is a quick example trying to illustrate the idea.

export function ExampleComponent(props) {
  const [spring, api] = useSpring(() => ({
    y: 0,
    config: {
      mass: 1,
      friction: 10,
      tension: 50,
      velocity: 100,
    },
  }));

useGesture(
    {
      onDrag: ({ delta: [, y]}) => {
        api.start({
          y: ScrollHandler(Math.floor(y * 2)}); // do some computations and return the position
      },
    {
      domTarget: window,
    },
  );

return (
    <a.group position-y={spring.y}>
      <mesh>
        <shapeGeometry args={[maskShape]} />
        <meshBasicMaterial attach="material" color={'#FF0000'} />
      </mesh>
        <a.group position-y={-spring.y}>  // here I would want the spring but as a negative value
          {props.children}
        </a.group>
    </a.group>
  );
}

You can see I am wanting the negative of the spring attached to the group holding the children.