http://shiftedbits.org Shift those bits. C'mon, shift em! Sun, 19 Apr 2009 19:42:04 +0000 http://backend.userland.com/rss092 en In the Cocoa frameworks, it is common to find mutable and immutable versions of classes that store data, such as strings, dictionaries, and arrays. Most of these classes also implement the NSCopying informal protocol, and those with mutable varients implement the NSMutableCopying protocol. These protocols specify methods for obtaining immutable ... http://shiftedbits.org/2009/04/17/nscopying-and-mutability/ To kick of the Coding Yups and Nopes section, I'll start with something simple. There are a set of things to do, and a set of things to avoid. For each thing, there are one or more reasons justifying its classification. These reasons are ordered by descending importance and increasing ... http://shiftedbits.org/2009/04/17/readable-if-statements/ This post kicks off the "App Yups and Nopes" section in which I'll post both good and bad things I see applications doing. This differs from the other Yups and Nopes sections in that it talkes specifically about observed application behavior. My intent is to show why a specific behavior ... http://shiftedbits.org/2009/04/16/window-resizing-on-resolution-change/ So I was talking with my friends a while back, deep into one of my frequent rants about ineptitude in the software industry, when it struck me that I should start blogging this stuff. Also, my friends pointed out that the manner in which I deliver my criticism is particularly ... http://shiftedbits.org/2009/03/26/regression-adobe-cs4/ As programmers on OS X are well aware, the units of mach_absolute_time() have been nanoseconds since 10.2, although this was only documented since 10.5. As the iPhone runs a slimmed down version of OS X, I thought it reasonable that the units would remain the same on the device. Not so. On ... http://shiftedbits.org/2008/10/01/mach_absolute_time-on-the-iphone/ My main Mac is out of service for a few days as the screen gets replaced, so I performed a Time Machine restore onto another computer to use in the meantime. I'll let this computer continue backing up to the same time machine volume, then do a TM restore back ... http://shiftedbits.org/2008/09/19/time-machine-switching-computers/ Quick bug fix update: 1.2.2 Fixes a crash due to a missing implementation of __KVOAdditions__dealloc__original__ on NSObject. 1.2.1 now runs on the iPhone. The new updates are in SVN at http://svn.shiftedbits.org/public/KVOAdditions/trunk and tagged at http://svn.shiftedbits.org/public/KVOAdditions/tags/1.2.2 http://shiftedbits.org/2008/09/13/key-value-observing-improvements-v122/ Hot on the heels of the 1.1 bug fix release comes version a freshly rewritten 1.2 with API cleanup, bug fixes, and a great new feature. Lately, I've been using observers to allow an object to observe changes to its own properties. This means I don't have to override the setter ... http://shiftedbits.org/2008/09/03/key-value-observing-improvements-v12/ Key value observing is quite a useful tool, no doubt about it. But it has a singularly annoying manner of informing the observer of a change. The -[NSObject observeValueForKeyPath:ofObject:change:context:] method is sent to the observer when a change occurs. It's up to the implementor to parse the `change' dictionary to ... http://shiftedbits.org/2008/07/24/key-value-observing-improvements/ As part of a graphics API I've been working on (for my own use, it's hardly ready for production,) I decided to try learning SSE optimization by making the compositing routine faster. I came up with an implementation which, according to my tests, is 3-5X faster than the non-optimized version. The ... http://shiftedbits.org/2008/01/29/sse-optimized-compositing/