When comparing Phaser.io vs Gosu, the Slant community recommends Phaser.io for most people. In the question“What are the best 2D game engines?” Phaser.io is ranked 10th while Gosu is ranked 47th. The most important reason people chose Phaser.io is:
Ranked in these QuestionsQuestion Ranking
Pro Very fast to develop with
Pro Good tutorials, courses and books
There are plenty of great learning resources available for Phaser.io.
Pro Super-simple loading of assets
Pro Great community resources
Pro Animating is easy
Pro Excellent tools for sprites
Pro Built-in Arcade Particle system
Pro Support for Arcade Physics, Ninja Physics and p2.js
Pro Easy to learn
Pro No install required
All you need to do is attach Phaser script to a HTML page even without installing any extensions.
Pro Very active development
This is one of the most developed frameworks right now.
Pro WebGL and Canvas rendering modes
You can choose WebGL or classic HTML canvas element for game rendering.
Pro Easy to learn
Most task are done just using 2 or 3 lines of codes...
Pro Has separate versions maintained by developer and the community
The creator of phaser(photonstorm) has given the older(Phaser 2.0) source code to the community for their own maintenance, and has made Phaser 3.0 with a different style and approach, trying to make it easier for beginners to learn.
Pro Easy to understand if you have used flash
Phaser provides a similar approach as to that of Flash games, where you can load assets and place them on a stage, and even improves upon the shortcomings of actionscript. It is very easy to shift from flash to HTML5 development because of this approach.
Gosu is not a game development framework, only a media library that happens to be suited to game development. (Kind of like SDL in the C world.) That means the interface is relatively small.
Pro Mature API, actively maintained and developed
Gosu has been under development since 2001. It is mature and has several toolkits built on top of it to provide additional functionality.
Pro Cross-platform, even mobile, using Ruby
Con Official documentation is not so good
Con Poor performance
As long as your map is not larger than 600*400px, everything is fine.
Con Developer ignores community needs
Con Extremely many bugs
Con Deploying Ruby apps is a mess
Games built with the Ruby to .exe "compiler" do nothing more than extract your source code and Ruby.exe to %TEMP%, then run it. The code is not really compiled at all. The process for wrapping games as Mac apps is a bit nicer, but you'll need a paid Apple Developer subscription to code sign the app, or users will see a warning/error when running your game.
The only way to really compile Ruby is to use RubyMotion, which does not work on Windows and requires a paid subscription on top of the Apple Developer one.
(This Con is not specific to Gosu. Deploying Ruby code has never been fun.)