[游戏开发]Nodejs+Unity使用Protobuf完成数据序列化与反序列化

一、后端nodejs Express

1、 安装应用生成器npm install express-generator –g
2、 生成项目Express --view=ejs TestProtobuf
3、 进入项目安装依赖包 npm install
4、 安装热更新 npm install -g nodemon ：配置package.json：“start”: “nodemon ./bin/www”
5、 npm install google-protobuf --save

D:\WorkSpace\NodeProjects\TestProtobuf

目录结构

protos目录下存放proto消息格式Asset.proto文件

protobuf.js相关语法参考
https://github.com/protobufjs/protobuf.js#examples

syntax ="proto3";
package protobuf;
message Asset{
   string code =1;
   string name =2;
   double px =3;
   double py =4;
   double pz =5;
   double rx =6;
   double ry =7;
   double rz =8;
   double sx =9;
   double sy =10;
   double sz =11;
   string location =12;
   string model =13;
   bool isDraw =14;
   string vecs =15;
   string color =16;
}

message AssetList {
   repeated Asset list = 1;
}

router下的assets.js，写一个get方法，请求message二进制文件

var express = require('express');
var router = express.Router();
var protobuf = require("protobufjs");

router.get('/', function(req, res, next) {
  protobuf.load("./protos/Asset.proto", function (err, root) {
    var arr =[];
    for(i=0;i<300;i++)
    {
      for(j=0;j<300;j++)
      {
        var obj = {code:'a'+i,name:'a'+i,px:i*1.1,py:0,pz:j*1.1,rx:0,ry:0,rz:0,sx:1,sy:1,sz:1,location:'root',model:'cube',isDraw:false,vecs:null,color:null}
        arr.push(obj);
      }
    }
    var payload = {list:arr};
    var msg = root.lookupType("protobuf.AssetList");
     var message = msg.create(payload); 
    // res.send(message);
     var buffer = msg.encode(message).finish();
     res.send(buffer);
  });
  
});

module.exports = router;

二、 前端Unity 2019.4.5f1 WebGL .NET4.x

C:\Users\PC-user\Documents\Visual Studio 2015\Projects\ConsoleApplication2

使用Visual Studio2015 新建控制台程序，右键解决方案-属性，修改为.NET FRAMEWORK4.6.1

NuGet安装Package获取相关dll

Install-Package System.Buffers -Version 4.5.1
Install-Package System.Numerics.Vectors -Version 4.5.0
Install-Package System.Runtime.CompilerServices.Unsafe -Version 6.0.0
Install-Package System.Memory -Version 4.5.4
Install-Package Google.Protobuf -Version 3.19.1

拷贝项目packages下lib的dll

packages\System.Buffers.4.5.1\lib\net461
packages\System.Numerics.Vectors.4.5.0\lib\net46
packages\System.Runtime.CompilerServices.Unsafe.6.0.0\lib\net6.0
packages\System.Memory.4.5.4\lib\net461
packages\Google.Protobuf.3.19.1\lib\net45

DLL插件放在Asset/Plugins下

下载protoc-3.19.1-win64，protoc.exe生成c#文件

1、cd 到 protoc-3.19.1-win64\bin目录下
2、protoc.exe生成c#文件

> protoc.exe --proto_path=./ asset.proto --csharp_out=./

asset.cs文件拖到Unity项目中

D:\WorkSpace\UnityProjects2021\Unity2019.4.5f1\TestProtobuffer

public IEnumerator GetData()
    {
        var url = string.Format("http://localhost:3000/assets");

        UnityWebRequest _request = new UnityWebRequest(url, UnityWebRequest.kHttpVerbGET);
         _request.downloadHandler = new DownloadHandlerBuffer();
        _request.SetRequestHeader("Content-Type", "application/octet-stream;charset=utf-8");
        
        yield return _request.SendWebRequest();
        if (_request.isHttpError || _request.isNetworkError)
        {
            Debug.LogError(_request.error);
        }
        else
        {
            IMessage IMasset = new AssetList();
            AssetList data = new AssetList();
            data = (AssetList)IMasset.Descriptor.Parser.ParseFrom(_request.downloadHandler.data);
            Debug.Log(data.List.Count);
            count_t = data.List.Count;
            CreateManyAsset(data);

        }
    }