I have been looking for a BCA software that can implement 3d geometry for multiple materials (both gas and solid). I am trying to simulate ion irradiation of a gas bubble inside a solid material.

I couldn't find any software that can readily do this, but RustBCA stood out to me as the closest option. I've been considering forking this repo and modifying the source code to allow my use case. I have a few questions regarding this:

• Will it be hard to implement a solid material around a gas sphere based on the current codebase?
• Do you have any suggestions about how to design such an implementation?
• Are there any future plans to allow multiple materials in 3d geometry?