D3Emu

D3Emu is a multi-platform Diablo III server emulator written in a mix of languages. The core portion of the server is written in C++, but there is a new GUI-based server (in xcode/d3emu-cocoa) written using Objective-C++ and Cocoa libraries.

If you're using the Xcode project, the header paths are all relative, and it assumes you installed the protobuf library to /usr/local/lib and /usr/local/include.