Raycastingpoint NaN on Mobile Device after OnTap

[oreMno]

Hi there,
I have an issue on mobile devices, for getting an invalid Raycastingpoint onTap event.

Here, the description:
Project
https://pchen66.github.io/Panolens/examples/panorama_infospot.html
What To Do
Open DevTools on Chrome, set mobile devices and click/tap the panorama. Set a breakpoint on panolens.min.js inside OnTap.
OnTap() is reached after OnMouseDown and no value is defined for a.clientX or clientY, because of touchEvent
this.raycasterPoint.x = (a.clientX - c.left) / g.clientWidth * 2 - 1;
this.raycasterPoint.y = 2 * -((a.clientY - d) / h) + 1;

Do you have any idea how to fix this for mobile device?