How do I add ClippingPlane to the specified position

**ENV: win10 64, chrome 64 **72.0.3626.109, **cesium 1.54 , ****graphics card:**hd graphics 630

I want to add an clippingPlane in the specified position,but i failed.

This is my code.

**Switch projects to BIM and **then select a point on the tileset, I want add the clippingPlane to the point position

demo page

I think this is the same problem as in this thread:

I explain a solution there as well as provide a Sandcastle demo that shows you how to create a clipping plane relative to a tileset correctly.