Currently putting the finishing touches to the iOS version of the Reality Augmenter. It’s pretty much feature complete and reliable, just tweaking the user interface and adding final touches.

It’s taken a lot to get here, I wanted to share as much of the code as possible with the OSX version. I’d already stuck to an MVC design pattern which meant most of the iOS work was re-building the view aspect, and rethinking how that would work in an iOS environment. I found the storyboards very easy to pick up and good way to work, and once I’d got the hang of tab and navigation controllers, the basic app built up very quickly.

On the controller side, I’d implemented quite a few things in NSArrayControllers, which aren’t available in iOS, but there wasn’t too much going on in them so could implement some shared classes between iOS and OSX that plugged into the original array controllers and provided the functionality I needed in iOS.

The toughest part was upgrading openGL. Originally the OSX version used a legacy profile because of the Quartz Composer functionality. While there is a fixed function pipeline in ES1, I really wanted to be able to use later versions of ES, which meant upgrading the original to core profile. This means practically all of the openGL code is shared between OSX and iOS, with only different shaders supporting the differences between core and ES. I could probably work on a shader compiler to further reduce differences, but for now I just have different shaders for different versions.

Of course, now there is Metal, and Swift has been taking off too. Once I complete the iOS version, and migrate it’s new features into the OSX version, I’ll be looking to switch the code base over to Swift and Metal.