Quoted from markmon:I am sure you can develop on C++ as well. They probably just made a C# library set and examples. But unity can work with C++. Also you don't have to use unity. That's only if you want cool 3D graphics. A lot could be done with static images and video sequences. I bet something neat could even be built out of the flash sdk.
Unity even supports JavaScript. I am really into learning Unity with my oldest son. He is doing the tutorials and having a lot of fun with it.
Aaron
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