Suitable Design pattern for building a 3D model

Suitable Design pattern for building a 3D model

I have implemented a 3D model application using DirectX api and C# .NET.
Initially started with an intention to make the 3D model working and by
now, all the code logic and UI stuff everything is in one *.cs file i.e.,
in main form.
Could you please anyone suggest me which design pattern is suitable for
segregating my code in a proper way?
As MVVM (Model-View-ViewModel) pattern is suitable for WPF application, Im
under the impression that the same design pattern can be suitable for 3D
rendering application.
Please suggest me if any other design pattern is well suitable for my 3D
modeling application. Thanks in advance.
Regards, Kumar