I needed to implement a function to convert an object from Graphics3D to Image3D, basically a 3D version of rasterisation (I need the geometry in a discretised form). I used the method suggested by R.M. in this post:How to convert Graphics3D object into an Image3D object?, and it's working as I wanted. However, I need to run my code within a kernel from a terminal, and the Show function being used in "slice" requires the frontend. Is there a way of substituting the Show function with something else that can be executed easily within the kernel?