This is Part 7 in the Making Of Chickens n Kittens series. Part 6 is here.
If you read Part 4 then you know that CnK was originally written in C++, but was then rewritten in C# with XNA in order to run on the XBox. But with the redesign that was done (see Part 6) it was obvious that the best platform for CnK was not the XBox 360, rather mobile devices with touch screens, like phones and tablets. This created a problem. By using XNA that meant CnK could run on the Windows Phone 7, but nothing else. And who even has a Windows Phone 7, anyway?
The choice was to either re-rewrite CnK in C++ so that it could run on Android and iOS, or buy licenses for MonoTouch, which at the time would have been about $400 for an iOS license and another $400 for an Android license. We went with the former. In late 2011 work began on re-rewriting CnK in C++. But so much of CnK, everything from math to the graphics to sound, was dependent on XNA, but XNA was only usable using C#, not C++. So what happened? Nxna, an XNA clone with the same (or at least very similar) API that works in C++ and runs on iOS and Android devices.
Time will tell whether it was worth it to spend all that time re-rewriting…