fennec

a free and open source game engine

Table of Contents

1. Introduction
   1. Coding Standards
2. Building from Source
   1. Building from Terminal
   2. Building on Windows
3. Running the Test Suite
4. Usage
5. Contribution
6. Documentation

Introduction

fennec is designed to be a general purpose, educational game engine. fennec may be used through the provided editor application, or as a standalone library to link against your application.

Coding Standards

Interfacing with the API in C++ follows the GNU Coding Standards. Some main areas where the engine strays from the GNU standard includes the following:

• Section 4.7, Standards for Graphical Interfaces. fennec provides an implementation for X11, however it does not use the GTK toolkit.

• Section 6.1, GNU Manuals fennec does not use Texinfo and instead uses Doxygen. Otherwise, it follows the other standards of this section.

• Section 7, The Release Process fennec follows most of the conventions in this section, however the build system used is CMake and not Makefile. CMake, although overwhelming at first, is much more friendly to those who are learning build systems for the first time.

fennec Standards:

• As per the GNU standard, macros should be SCREAMING_SNAKE_CASE. Additionally, Macros should be preceded by <APP_NAME>_. Macros that wrap C-Style functions may use normal snake_case.

• Header Guards should be implemented using #ifndef, #define, and #endif for portability. The naming convention for Header Guards is as follows: <APP_NAME>_<DIRECTORY_PATH>_<FILE_NAME>_H. I.E. the engine file fennec/lang/utility.h has the Header Guard FENNEC_LANG_UTILITY_H.

• Helper Functions, in the case of classes, should be private. In the case of global functions, helpers should be placed in a similarly named file in a subdirectory and namespace called detail. Helper functions should be documented with C-Style comments, however it is not necessary to provide Doxygen documentation.

• DO NOT USE C++ EXCEPTIONS they will not be supported because they are shit. No, I won't elaborate.

The C++ stdlib is reimplemented in the fennec engine. There are a few reasons for this:

1. Standardize implementations across compilers
2. Set proper naming conventions, i.e. std::vector → fennec::dynarray
3. Optimize compilation times, binary size, and performance.
4. Inject debugging information when necessary.
5. Expose functionality in a readable manner for those interested in learning the intricacies of the implementation.

Building from Source

fennec uses the CMake build manager. The CMake build script provides several targets for building parts of the engine.

Using an IDE will streamline the build process for you and add additional configuration options. Eclipse, Visual Studio, and CLion provide built-in support for CMake. VSCode is also a viable IDE but involves some extra setup.

Target	Description
fennec	The main engine target.
fennec-metaprogramming	Generate metaprogramming info for the fennec library. A dependency of the main engine.
fennecdocs	Generate html documentation for the engine. Requires Doxygen.
fennecdocs-clean	Cleans the generated html documentation files.
fennec-test	Test suite for verifying engine functionality.

Dependency	Notes
C/C++ Compiler	GCC/G++ is the compiler that fennec is designed around, however, Clang, MSVC, and MinGW may also be used
CMake	The build manager used by the engine
A build system	Any build system will work, however, build.sh uses Ninja by default.
A memory debugger	Any memory debugger will work, however, test.sh uses Valgrind by default.
Doxygen	Doxygen is required for building the documentation for fennec. This is an optional dependency
Graphviz	Graphviz is a required dependency for Doxygen

Building from Terminal

build.sh provides profiles for building the main engine. Run ./build.sh --help for more info.

By default, the CMake generator used is Ninja, which requires Ninja to be installed. You can modify the build scripts to use another build manager, see the CMake documentation for available generators.

Building on Windows

The bash script can be run natively on Windows when WSL is enabled. You do not need to run the script in WSL, simply use the "bash" command in Command Prompt or PowerShell. The script will require the build dependencies installed and configured to be available on the PATH environment variable.

Fore more details, see this blog post for Windows Build 14316.

Otherwise, follow the sequence of commands provided in the bash script.

mkdir -p build/<profile>
cd ./build/<profile>
cmake -G Ninja -DCMAKE_BUILD_TYPE=<profile> -S ../.. -B .
cmake --build . --target fennec

The value of <profile> may be one of the following:

Profile	Description
Debug	Build in debug mode, provides full debugging information to use with a debugger.
Release	Build in release mode, provides full optimizations, eliminating debug info.
RelWithDebInfo	Build in release mode with extra debug info, provides partial optimizations.
MinSizeRel	Build in release mode but optimizing for minimum binary size.

If you would like to use Visual Studio without CMake, you can use the build script to generate a Visual Studio project for the source. For a list of available Visual Studio generators, see this section. Running the following command will generate the Visual Studio project.

cmake -G "Visual Studio 17 2022" -A x64

Running the Test Suite

test.sh provides profiles for building the test suite and executes them.

By default, it runs in debug mode and the first failed test will throw an assertion. Any tests that involve running as an application will spawn a subprocess with a window, and give a short description of the behaviour in the terminal. It will then have you confirm whether the information displayed is correct.

Usage

Contribution

There are some principles to keep in mind when contributing to fennec.

1. You must follow the style guide provided by the GNU Coding Standard.
2. Any changes must allow all projects to be forward compatible with newer engine verisons.