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本文皆在教您如何對 DDNet 開發 ，因為這是一款開源遊戲（原始碼公開），它依賴於一些善良的人們在空餘時間的貢獻。

你的開發環境

截至目前，處於一下原因，我們強烈建議使用Linux環境在DDNet中開發：

• 大多數DDNet貢獻者實際上使用Linux來貢獻。
• 更容易的軟件包管理，您可以輕鬆地安裝所有需要的庫並開始貢獻。
• 本文還沒有Windows版本，主要關注Linux。

首先，DDNet是使用 C++ 語言編寫的，您需要相當熟悉它，但您也可以了解基礎知識並了解更多信息。

學習C++的一些有用資源：

• learncpp.com
• cppreference.com
• 百度。

DDNet的原始碼使用Git託管，這是一個版本控制系統，也是與多個開發人員協作的重要工具。

如果您的Linux發行版中還沒有git，請安裝它，例如在大多數基於debian/ubuntu的發行版中，你可以打開終端，輸入：sudo-apt-install git。

獲取原始碼

原始碼位於Github，您可以在不需要帳戶的情況下通過Clone獲得原始碼，但如果您想將更改放入官方原始碼，則需要一個賬號。

如果您不熟悉git/github，可以在這裏學習基本知識： Hello World - Github

下載依賴項

如果您在Linux上，您可以通過閱讀DDNet github頁面上的自述文件來安裝所有需要的依賴項：https://github.com/ddnet/ddnet#dependencies-在linux上--macos

對於Arch Linux：

控制台輸入 sudo pacman -S --needed base-devel cmake curl freetype2 git glew gmock libnotify opusfile python sdl2 sqlite wavpack

For Debian:

sudo apt install build-essential cargo cmake git glslang-tools google-mock libavcodec-extra libavdevice-dev libavfilter-dev libavformat-dev libavutil-dev libcurl4-openssl-dev libfreetype6-dev libglew-dev libnotify-dev libogg-dev libopus-dev libopusfile-dev libpng-dev libsdl2-dev libsqlite3-dev libssl-dev libvulkan-dev libwavpack-dev libx264-dev python rustc spirv-tools4

編譯DDNet

我們使用CMake來控制編譯進程，如果你所有的依賴項都下載了，那麼它會很簡單，只要輸入這些命令（確保你在DDNet文件夾下）：

mkdir build
cd build
cmake ..
make -j$(nproc)

通用信息

以下是一些通用信息：

• 目前，原始碼是使用C++17標準編譯的，但您會看到代碼的許多部分更像C，因為只有大多數新代碼使用C++17。
• std::string很少使用，字符數組加system.h方法才是常態。
• 大多數輸入輸出代碼、格式化和Print都是使用system.h提供的方法完成的。

原始碼佈局

現在你可以構建DDNet了，可以開始編輯它了。

src/base 目錄

由於DDNet是一個跨平台遊戲，需要一個抽象層來簡化開發，因此該目錄包含許多有用的函數來處理這一問題。

src/engine 目錄

遊戲引擎就在這裏，它處理大多數與遊戲無關的東西，比如圖形、聲音、網絡等。

src/game 目錄

所有玩遊戲的代碼都在這裏，分為客戶端和伺服器。

伺服器端

這個遊戲使用自己的實體組件系統，所有其他實體派生到的主類是CEntity，位於src/game/server/Entity.h中。

這些實體由位於此處的遊戲世界管理src/game/server/gameworld.h

一些重要實體有：

CCharacter: 代表着一個tee 是活着的, 當一個tee產生時它被實例化，當它死亡時它被刪除。有關玩家在死亡之間的信息，請參閱CPlayer.

客戶端

The client side is made up of components, these are classes that inherit CComponent: These components can implement the virtual methods such as OnInit, OnMessage, etc. to provide their functionality.

Networking

The network protocol is mostly generated by python scripts that output C++ code, for example, datasrc/network.py defines all network packets.

Code conventions

The ongoing discussion on code conventions is located here: ddnet#2945

Currently, the following applies:

Indentation style

Allman style is used.

This style puts the brace associated with a control statement on the next line, indented to the same level as the control statement. Statements within the braces are indented to the next level.

while(x == y)
{
    Something();
    SomethingElse();
}
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
FinalThing();

Classes and Structs

Must be prefixed by C (for legacy reasons this is ignored for structs in some places, such as in graphics code) or I for interfaces. New structs should be prefixed by S.

Example:

class CCharacter : public CEntity
{
    // ...
}

Enums and constants

Should be screaming snake case, for example: MAX_PLAYERS

enum
{
	FAKETUNE_FREEZE = 1,
	FAKETUNE_SOLO = 2,
	FAKETUNE_NOJUMP = 4,
	FAKETUNE_NOCOLL = 8,
	FAKETUNE_NOHOOK = 16,
	FAKETUNE_JETPACK = 32,
	FAKETUNE_NOHAMMER = 64,
};

Variable naming

• The names of variables contain 3 parts: qualifier, prefix and name.
• Variable names should start with uppercase unless they are 1 char long without any prefix or qualifier, for example: i, x, y.
• Variables can have more than 1 qualifier (or zero) and more than 1 prefix (or zero).

These are laid out like this: [qualifiers]_[prefixes][Name]

Qualifiers

• m for member variables: m_MyVariable.
• s for static variables: s_MyStaticVariable, ms_MyStaticMemberVariable.
• g for global variables with external linkage: gs_MyGlobalStaticVar.

Prefixes

• p for pointers: pMyPointer, m_pCharacter, ppMyPointerToPointer.
• a for arrays: aMyArray, aBuf.
• v for std::vectors: vMyVector, vpvMyVectorOfPointersToVectors.
• fn for functions: pfnMyCallback, m_papfnMyPointerToArrayOfCallbacks.

Common snippets

Here is a list of code that you may frequently see across the codebase:

Formatting text

char aBuf[128];
str_format(aBuf, sizeof(aBuf), "number: %d", 2);

See printf documentation for a list of all format specifiers.

Iterating over all players

for(int i = 0; i < MAX_CLIENTS; i++)
{
    // Server-side
    CPlayer *pPlayer = GameServer()->m_apPlayers[i];
}

Printing to the game console

Console()->Print(IConsole::OUTPUT_LEVEL_STANDARD, "wikiprint", "Hello from the ddnet wiki!");

Debug printing

int i = 2;
dbg_msg("wikiprint", "Hello from the ddnet wiki: %d", i);

Translating text in the client

Localize can be used in the game client to get the translation for a specific string from the language file selected by the user.

DoButton(..., Localize("Connect"), ...);

The string can also contain format specifiers. The translated string must contain the same format specifiers.

char aBuf[128];
str_format(aBuf, sizeof(aBuf), Localize("%d of %d servers"), NumServers, TotalServers);

A script is used to scan the code for calls to Localize and collect the strings to update the translation files. For this reason, the call to Localize must not contain any other code, or the script cannot determine the text correctly.

// Do NOT do this:
const char *pStr = Localize(Team == TEAM_RED ? "Red team" : "Blue team");
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
// Do this instead:
const char *pStr = Team == TEAM_RED ? Localize("Red team") : Localize("Blue team");

External resources

• UI Code in DDraceNetwork by Ryozuki
• An intro to the DDraceNetwork game source code by Ryozuki
• Code conventions in DDraceNetwork by Ryozuki
• Implementing a chat command in DDraceNetwork by Ryozuki
• Auto generated docs
• Technical documentation of Teeworlds file formats and network protocol
• The Anatomy of a One Tick Unfreeze
• Teeworlds programming YouTube tutorial by ChillerDragon