Geometries below geoid surface

I am drawing cones under the surface of the earth, and end up building a new earth (time-space) geometry
I am able to remove the earth, but still the earth hides the parts of geometries under the surface.
have read many posts, with for instance solutions with the groundpush plugin or the translucent terrain, but my case is so simple that I hope that a simpler solution exists.
Thanks for help,

Hello Alain,

Unfortunately, we don’t have a good solution for subsurface geometry at the moment. However, it is a highly requested feature and we would like to add support sometime soon. I believe we want to finish implementing the 3D Tiles specification first though.



Dear Hannah,
thanks for your kind reply. Unfortunately this is really blocking for me, I will be obliged to turn to another solution and abandon Cesium

Hello Alain,
maybe what you need is not Cesium because you don’t use the representation of the Earth. Maybe you just need a more basic library like three.js?
You can check here and here.

Hello Farouk,
nice to hear from you!
You confirm then my current analysis, Cesium has too many functionalities that I don’t need.
As I am not at ease with java, I prefer not to invest time in learning three.js. I am now using Tulip software that I have been knowing and appreciating for a while.