Conical objects or extruded polygon with different geometry on bottom and top

I am trying to create irregular dome with different bottom and top.
Now i must create many polygons with specific height (cesium_object.png)
Exist easier way to create this object with one geometry? My solution is hard on computing time and rendering, because sometimes there thousands of layers and looks like and looks like terrible.
I cant find geometry type or primitive, which can create these object.

Thx for help.

Can you share a Sandcastle example ( of how you’re currently creating this geometry? You can click “share” in the top and paste the link you get here.

We did recently add the ability to make partial ellipsoids, which might help creating a shape similar to this:

If that doesn’t help, your other option might be to create your shape in a 3D authoring program like blender and export it as a glTF model and load it in CesiumJS that way. You can host the model or tile it on Cesium ion ( which will help performance if it’s a complex piece of geometry.

I create sandcastle example - example for non-regular object
i am try to create non-regular object, which will have different top and bottom polygon (same vertex count, but in different positions) or object which can looks like a low poly hemisphere.