DAMBI Engine

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Introduction

Dambi Engine is an Open Source SW Project for Game server architecture. Dambi Engine provides architecture to help users to make fast-working server through some techniques. Dambi Engine uses standard C++ libraries and Window APIs to make sure of stable environment.

• There are Several techniques we used.

  • Multi-Threading - Divided functions by their features. It helps program works more faster.

  • IOCP - Windows I/O model with great performance.

  • Lock-free Queue - C++ template libraries for multi-core processor.

Who needs Dambi?

• who has difficulty with starting game server
• who wnats to make multi-player game with his local device
• everyone who is interested in developing game!

What can I do with Dambi?

Dambi Engine provides basic game server architecture with several threads and objects. Users can build server with adding additional features everything they need and accept their clients through their customized server environment.

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If You want to check out more details about our project, Please read our Proposal Report

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Installation

Dmabi engine is a framework working on Window OS and Standard C++ in visual studio IDE.

Plaese download the project and build through IDE.

• Check all the header and source files are in the right folder

• To use Lock-free queue provided by intel open source, Please download the tbb and add to external libraries.

• Fill your own server IP & Port

//main.init()
if (!pServerObject->CreateSocket("your own IP", your own Port num))
{
	LOG_ERROR("Create Server Socket Error");
	return;
}

• Build a project to make .exe file
  
  

How can I Customize my own Server?

• In case of CPU acceleration, the number of worker threads can be set as sysinfo.dwNumberOfProcessors*2.

std::thread* Worker;
	for (int i = 0; i < sysinfo.dwNumberOfProcessors; i++)
	{
		Worker = new std::thread(WorkerThread, pServerObject->GetIocpPort());
		pMainConfig->ThreadList.push_back(Worker);
	}

• Set Socket Buffer Size

int nSockBufSize = 8192; 
	setsockopt(Socket, SOL_SOCKET, SO_SNDBUF, (const char*)&nSockBufSize, sizeof(nSockBufSize));

• client socket buffer size(NETWORK LENGTH)

const int G_MAX_NETWORK_LENGTH = (1024 * 1024);	

• change your queue(std::queue or tbb::concurrent_priority_queue)

tbb::concurrent_priority_queue<QueueCapsule*, std::greater<int>> Logicqueue;
std::queue<QueueCapsule*> Logicqueue;

• How to use lock-free-queue

#include <iostream>
#include <tbb/parallel_for.h>
#include <tbb/concurrent_queue.h>
 
int _tmain(int argc, _TCHAR* argv[])
{
    tbb::concurrent_queue<int> queue;
 

    queue.push(i);
 
    int num;
    while (queue.try_pop(num))
        std::cout << num << " ";
 
    return 0;
}

• Comparison of logicQueue speed by number of workerthreads (unit: ms)

	1	2	4	8
std lock(mutex)	4782	8468	12535	17151
lock-free(tbb)	5389	5215	4318	2671

• You can change the overlapped struct your way.

	BYTE* pRecvBuffer;
	UINT m_nRecvLength;
	OVERLAPPED* GetOverlapped() {
		return &(RecvBuffer.m_wsaOver);
	}
	WSABUF* GetWsaBuf(LPBYTE pBuff, UINT unLen) {
		RecvBuffer.m_wsaBuf.buf = (char*)pBuff;
		RecvBuffer.m_wsaBuf.len = unLen;
		return &(RecvBuffer.m_wsaBuf);
	}

• You can customize it by adding your own threads.

#pragma once
void LogicThread();
void LogThread();
void WorkerThread(HANDLE hIOCP);
void AcceptThread(SOCKET ServerSocket);

• Except for winsock, standard C++ is used, so you can make it work on other operating systems if you want. (For example on Linux, just add epoll)

stdafx.h
#pragma once
#include <iostream>
#include <thread>
#include <chrono>
#include <conio.h>
#include <string>
#include <queue>
#include <mutex>
#include <tbb/parallel_for.h>
#include <tbb/concurrent_queue.h>
#include <fstream>
#include <iomanip>
#include <ctime>
#include <WinSock2.h>
#include "Logger.h"

• You can create your own protocol by adding commands and structs.

#pragma once
typedef enum CMD
{
	PACKET_SEND = 0x0001,
};
typedef struct S_PACKET_HEADER
{
	USHORT	unCmd;
	UINT	unLen;
	S_PACKET_HEADER() {
		ZeroMemory(this, sizeof(S_PACKET_HEADER));
	}
} S_PACKET_HEADER, * PS_PACKET_HEADER;

typedef struct PACKET {
	int number;
	int age;
	char packet[10];
	PACKET() { Init(); }
	void Init()
	{
		memset(this,0, sizeof(PACKET));
	}
}PACKET;

• To add Log for debugging

LOG_DEBUG("Error msg");		//print debug
LOG_ERROR("Error msg");		//print error
LOG_FATAL("Error msg");		//print fatal
LOG_INFO("Error msg");		//print info

Demo Play

• Capture Images of Playing demo for dummy Client

Support

contributing.md

Contact

E-mail Us!

License

Dmabi Endine is licensed under Apache License, Version 2.0.. By its terms, contributions submitted to the project are also done under that license.