_updateScroll(lastXDelta, lastYDelta) {
        for(let i = 0; i < this.planes.length; i++) {
            // if our plane is watching the scroll, update its position
            if(this.planes[i].watchScroll) {
                this.planes[i].updateScrollPosition(lastXDelta, lastYDelta);
            }
        }

        // be sure we'll update the scene even if drawing is disabled
        this.renderer.needRender();

        this._onScrollCallback && this._onScrollCallback();
    }
Handles the different values associated with a scroll event (scroll and delta values)
     If no plane watch the scroll then those values won't be retrieved to avoid unnecessary reflow calls
     If at least a plane is watching, update all watching planes positions based on the scroll values
     And force render for at least one frame to actually update the scene
*