When comparing Cocos2d-x and Cocos Creator vs SFML, the Slant community recommends Cocos2d-x and Cocos Creator for most people. In the question“What are the best 2D game engines?” Cocos2d-x and Cocos Creator is ranked 10th while SFML is ranked 35th. The most important reason people chose Cocos2d-x and Cocos Creator is:
25% of iPhone games are made using Cocos2d-x. This means you will not be alone in development, and will have access to a large community. You'll know you are developing for an engine that works.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro A proven engine for mobile development
25% of iPhone games are made using Cocos2d-x.
This means you will not be alone in development, and will have access to a large community. You'll know you are developing for an engine that works.

Pro Good documentation
Documentation includes a programming guide, API reference, video tutorials and massive reference test code project showing all functions and giving working code to the user.

Pro Supports 3D models with skeleton animation
A new feature since Cocos2d-x v3.1 is support for 3D models (in your 2D game), not only this but support for skeleton animations is included too! This awesome feature allows for impressive characters in your game along with easier, more fluid and realistic animations.
Pro Great script language support
It supports Lua and Javascript with full feature support.
Especially with Cocos2d-JS you can develop games cross web and native, and the native solution have great performance with JS Bindings, much better than hybrid solution.

Pro Highly active community for questions and support
Cocos2d-x forums are active.
Pro OpenGL hardware acceleration

Pro Future-proof
Cocos2d-x is not only open source but also supported by Chukong Technologies of China and USA.
Regularly updated and adding support for the latest technologies. 2014 has already seen the release of Version 3, a new Cocos Studio development toolkit (optional) and support for new technologies like skeleton animation systems Spine and Adobe DragonBone.
Pro Greater performance than high level APIs
Cocos2d-x is C++ based engine and it has CPU advantages for most platforms because of that. It uses polygonal mesh methods for sprite rendering for using GPU advantages. (You also use quad methods for benefit CPU).
Pro No external dependencies
Because it is based on Pyglet.
Pro One code for all platforms
On top of supporting pretty much all existing platforms (except consoles), Cocos Creator (Cocos's IDE) allows you to write 1 code that runs on Android, iOS, Windows, MacOS and HTML5 (not Linux though).
Pro Easy integration of 3rd party plugins
Through the use of SDKBox you can easily integrate 3rd party SDKs and plugins for each version of Cocos2D (Lua, C++ or JavaScript), you just choose the SDKs to integrate and SDKBox will do the rest.
For example, if you want to add a rating plugin, you use sdkbox::PluginReview::init();
and if you want to add the Vundle Ad Network SDK, you use the one packaged in SDKBox SDKBOX sdkbox::PluginVungle::init();
.
Pro Allows for easy debugging
It has a built-in Python interpreter that allows for easy debugging.
Pro Very good IDE
Cocos Creator (Cocos' IDE) comes with scene editing, UI editor, animations & particle editors and whatnot. It's also easy to use and pretty intuitive if you read the official documentation & tutorials. Way way better than the old CocoStudio.
Pro Great video tutorials
Hundreds of video tutorials available.
Pro Very efficient and usable
Pro Zlib/PNG license
In short, SFML is free for any use (commercial or personal, proprietary or open-source). You can use SFML in your project without any restriction. You can even omit to mention that you use SFML -- although it would be appreciated.
Pro Can be combined with OpenGL
If you hate something about the way SFML handles graphics, you can just combine it with OpenGL. It's completely smooth and works as expected, without any additional dependencies.
Pro Active community and wiki
You can ask questions on their own personal forum which is full of users, and their wiki is constantly being maintained. They even have an IRC.
Pro Works on every platform
SFML 2.2 brought forth Android & iOS functionality, and SFML games work on Linux, Mac and Windows out of the box, since SFML is written with OpenGL.

Pro Great documentation
SFML is very well documented, even with short examples of use for many functions and modules. Furthermore, there are books like 'SFML essentials' and 'SFML for game development' which teach you how to use this library to its fullest.
Pro Good for OpenGL
If you are thinking about using OpenGL, look no further, you can open a window, and handle events in less than 15 lines, and it provides input, time, and even networking, plus alot more. It has become my favorite c++ library :D
Pro Great library
SFML is a collection of modular, well designed libraries you can implement an engine or game on top of. The API provides tons of good documentation and is very straightforward to use. You can get a game up and running with SFML quite quickly and with minimal effort.
Pro Clean code
An SFML project's code-base is usually clean and easy to read. All public SFML classes are under the namespace "sf" so it is easy to tell which code is yours and which belongs to SFML (of course you can stop this by typing using namespace sf;
).
Pro Available in many languages
There's support for many languages besides C++, current supported languages are: C, .NET, Crystal, D, Euphoria, Go, Java, Julia, Nim, OCaml, Pascal, Python, Ruby and Rust, and this list is constantly growing.
Pro Beginner-friendly
SFML is extremely beginner friendly and even provides pre-built libraries for your IDE of choice on Windows. Besides the fact that it's extremely well documented, they also have a set of tutorials that walk you through every module.
Pro Modern C++11 implementation
SFML is one of the few good C++ frameworks out there to actually make full use of the language. It's extremely well optimized and it plays well with anything you throw at it.
Cons
Con Poor support and non-existent community
Up until 2013, this was one of the best engines around. However, since then it was bought by a Chinese company and began stagnating - it's virtually in a slow death. Most developers abandoned Cocos in favor of more modern solutions leaving the community weak and the forums with little or no traffic. Although the Cocos2d-x Forum seems to have a decent community going.
Con No Graphics user interface
Con Modest functionality
Almost all free alternatives are more convenient, faster, and more functional.
Con Relatively slow
Compared to SDL2, GLFW, it is slow.
Con No GUI editor or IDE
Does not include any IDE or media editor. It's purely source code.
Con May take longer to learn and understand
Con Messy sprite management
Sprites retain all of the operations applied to them, whether that be a new position or a rotation. This makes sprite management somewhat annoying.
Con Not specifically a 2D game engine
It isn't really an engine, more of a collection of modular, well designed libraries you can implement an engine or game on top of.
