Doing the 2nd edition of Unity in Action mostly involves updating code listings for the latest version of Unity, but my editors and I also decided to add one new chapter. While the majority of feedback from readers has been (thankfully!) very positive, one thing we’ve frequently seen is people wishing there was more content about 2D games. Thus, we decided to add a chapter about developing 2D platform games.
My process for every chapter has been 1) first build the project, then 2) write about what I implemented. So I implemented the shell of a 2D platformer a couple weekends ago, and am now writing the chapter about it. Here is a WebGL build of that project:
(controls explained on that page; left/right move, Space jump)