This is an engine and editor (Like unrealED or unity3d) that is wrote in C++ and C#. Mostly C# but some core components are wrote in C++. I am the lead developer/designer of the engine, and am hoping to eventually profit via crowd funding(Such as patreon) - Since it will be crowd funded, I am making the engine open source.
Here is the current code base, on GitLab.
https://gitlab.com/vivid-research/vivid3dsharp
If the engine does start to be funded via public funding, there will be a split of profits with anyone joining the project.
Thanks.
You may contact me at mailto:antonyrobwells@gmail.com