What? A thing I made has just been open-sourced by my employers at Agant: the AGTTwoDimensionalDictionary works a bit like a normal dictionary, except that the keys are CGPoints meaning we can find all the objects within a given rectangle. Why? A lot of time on developing Discworld: The Ankh-Morpork Map was spent on performance [...]
This is a post that had been boiling for a while; I talked a little about the topic when I was in Appsterdam earlier this year, and had a few more thoughts which were completely supplanted and rearranged by watching
I’ve been reading the Smalltalk-80 blue book (pdf) recently, and started to wonder what a Smalltalk style object browser for Objective-C would look like. Not just from the perspective of presenting the information that makes up Objective-C classes in novel ways (though this is something I’ve discussed with Saul Mora at great length in the [...]
We’ve all got little libraries of code or scripts that help us with debugging. Often these are for logging information in a particular way, or wrapping logs/tests such that they’re only invoked in Debug builds but not in production. Or they clean up your IDE’s brainfarts. Having created these debug libraries, how are you going [...]
I’m pretty sure @bbum must have worn through a few keyboards telling users of StackOverflow not to rely on the value of an Objective-C object’s -retainCount. Why? When we create an object, it has a retain count of 1, right? Retains (and, for immutable objects, copies) bump that up, releases (and, some time later, autoreleases) [...]
An article that recently made the rounds, though it was written back in September, is called Apple’s Idioten Vektor. It’s a discussion of how the CCCrypt() function in Apple’s CommonCrypto library, when used in its default cipher block chaining mode, treats the IV (Initialization Vector) parameter as optional. If you don’t supply an IV, it [...]
This post will take a high-level view of some of Lion’s new security features, and examine how they fit (or don’t) in the general UNIX security model and with that of other platforms. App sandboxing The really big news for most developers is that the app sandboxing from iOS is now here. The reason it’s [...]
This post summarises my opinions of Windows Phone 7 from the Microsoft Tech Day I went to yesterday. There’s a new version of Windows Phone 7 (codenamed Mango) due out in the Autumn, but at the Tech Day the descriptions of the new features were mainly the sorts of things you see in the Microsoft [...]
I’m writing some library code at the moment that needs to work on both Mac OS X and iOS. The APIs I need to use on each platform are different, so I need different code on each platform. I also happen to think that putting both versions of the code in the same implementation file [...]
This article introduces the concept of key stretching, using code examples to explain the ideas. For code you can use in an app that more closely resembles current practice, see Password checking with CommonCrypto. There’s been quite the media circus regarding the possibility that Sony was storing authentication credentials for its PlayStation Network credentials in [...]
