README.md

UProtobuf

• Unreal Engine Third Party Plugin of the google protobuf libraries
• current protobuf version 3.12.3

Usage

Include the plugin in the project

• Add the plugin to your project (e.g MyProject/Plugins/UProtobuf)
• Add the module dependency to your module (Project, Plugin); In the MyModule.Build.cs file:

        PublicDependencyModuleNames.AddRange(  
		new string[]  
		{  
		...  
		"UProtobuf",
		...  
		}  
		);  

Compile the *.proto file

• The protobuf compiler protoc.exe is under the folder UProtobuf/Source/ThirdParty/tools
• Use protoc.exe to compile the .proto file to generate .pb.cc and .pb.h files. (eg .\protoc.exe --cpp_out=. .\<My Proto>.proto)

Build protobuf library from source code in Window

• Protobuf installation tutorial links https://github.com/protocolbuffers/protobuf/blob/master/src/README.md https://github.com/protocolbuffers/protobuf/blob/master/cmake/README.md
• Unreal Engine requires the Runtime Library property of protobuf library is 'MD_DynamicRelease'. To change the Runtime Library property, change the file protobuf-3.12.3\cmake\CMakeLists.txt, before compiling. To change the property from 'MT' to 'MD', simply just comment these three lines.

  if (MSVC AND protobuf_MSVC_STATIC_RUNTIME)
    foreach(flag_var
        CMAKE_CXX_FLAGS CMAKE_CXX_FLAGS_DEBUG CMAKE_CXX_FLAGS_RELEASE
        CMAKE_CXX_FLAGS_MINSIZEREL CMAKE_CXX_FLAGS_RELWITHDEBINFO)
#      if(${flag_var} MATCHES "/MD")
#        string(REGEX REPLACE "/MD" "/MT" ${flag_var} "${${flag_var}}")
#      endif(${flag_var} MATCHES "/MD")
    endforeach(flag_var)
  endif (MSVC AND protobuf_MSVC_STATIC_RUNTIME)