Ejecta has been formerly known as iOSImpact. It still shares the same idea and some basic code with iOSImpact, but is otherwise a significant rewrite of it.
The whole Canvas implementation has been re-implemented from scratch and is now much faster, more robust and closer to the HTML5 spec. It also supports the vector drawing functions, such as
stroke() as well as
getImageData() and many others.
iOSImpact used a lot of Impact specific hacks and you needed a special set of plugins to make Impact work with it. This is no longer the case – Impact games now work without any modifications or plugins in Ejecta.
Ejecta has become much more generally usable. It's not only a tool to get Impact games running on iOS, but can also be used for many other Canvas animations and games.
Because Ejecta is no longer focused on Impact only, I decided to release it as Open Source to see what the community comes up with. I'm also hoping that the community will help out to fill the last gaps in the Canvas implementation and also provide some more functionality such as in-app purchases or WebSocket support.
I also wrote a bit about some implementation details in my blog.