Is it possible to use C++ with Unity instead of C#?

Question

The title kind of says it all. Is it possible to replace C# with C++ on a game using Unity?

Answer 1

It is possible to use C++ with the Free version of Unity, although it is easier to work with if you have a Unity Pro license. All you have to do is wrap it up in a DLL and follow the instructions below on where to place it.

I wrote an article that covers this topic: Unity and DLLs: C# (managed) and C++ (unmanaged)

For Unity 4 Free:

• Add unmanaged code to the Unity Project Root: UnityProject
• Add managed code to the Plugins folder: UnityProject->Plugins
• When you build a project, copy the unmanaged code to BuildRoot->Data->Plugins

For Unity 4 Pro and any Unity 5:

• Just copy the DLLs into UnityProject->Plugins

Unmanaged means C++ and Managed means C#

Answer 2

It is possible though inconvenient. You'd have to write managed C++ to achieve it. And yes, there is such thing as managed C++. Managed doesn't specifically mean C# and unmanaged C++. To achieve it you'll need to import UnityEngine DLL file. When you're finished you put it in the (Unity Project Name)/Plugins folder. Here would be the code you'd use: In the C++ file:

public ref class CPPUNITY {
  public:
     void Start() {
         Debug::Log("C++ printed message");
     }

};

In the C# file:

     using UnityEngine;
     public class FileName {
         void Start() {
              CPPUNITY.Start();
         }
     }

That exact code wouldn't work but thats a base.

Answer 3

Yes, you can use https://github.com/jacksondunstan/UnityNativeScripting

This is basically a code generator which allows you to write C++ code which calls generated C# bindings. Your C++ is then compiled to a binary "Unity plugin" which can be used in your game. Of course, the README of the above repository goes into a lot more detail.