Cocoa with Love

5 ways to draw a 2D shape with a hole in CoreGraphics

May 17, 2010 (an Objective-C era article)

In this post, I look at 5 different ways that you can draw a very simple shape: a square with a triangular hole cut out of the center. In a drawing environment like CoreGraphics which offers double buffering, winding count path filling, even-odd path filling and clipping regions, there's no single answer. An iPhone sample project is provided containing the code but all drawing functions are identical on the Mac.

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A look at how malloc works on the Mac

May 12, 2010 (an Objective-C era article)

In this post, I'll take a high-level look at how malloc is implemented on the Mac. I'll look at how memory is allocated for "tiny", "small" and "large" allocation scales, the multi-core performance improvements introduced in Snow Leopard and some inbuilt debugging features you can trigger for finding memory problems including buffer overruns.

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Finding or creating the application support directory

May 6, 2010 (an Objective-C era article)

A simple post this week but one which optimizes a common task: locating the application support directory for the current application, creating it if it doesn't exist. The result makes accessing the current application's support directory a single line and provides a structure for locating and creating folders at other standard locations with similar ease.

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Porting a Mac program to Windows using The Cocotron

Apr 27, 2010 (an Objective-C era article)

In this last of three posts about porting a Mac application to Windows, I look at the steps involved in setting up The Cocotron with a remote debugging session between Xcode and the application running on Windows. I'll also talk about the code that didn't "just work" and some of the approaches I used to fix the program and get it working.

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Design of a multi-platform app using The Cocotron

Apr 21, 2010 (an Objective-C era article)

In this post, I'll talk about how multi-platform applications are structured and talk about some of the different ways that applications separate core logic from platform specific behaviors. I'll talk about how using a porting layer like The Cocotron fits into these designs and why using The Cocotron doesn't necessarily mean that you're ignoring best-practice or creating a second-class application.

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Options for porting Objective-C/Cocoa apps to Windows

Apr 15, 2010 (an Objective-C era article)

There are a few different options for porting Objective-C/Cocoa applications to Windows. Each option has different advantages and offers different capabilities. In this post, I'll give an overview of some of these options, their advantages and disadvantages.

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Network data requirements on iPhone OS devices

Apr 7, 2010 (an Objective-C era article)

If your iPhone OS application makes heavy use of the network, there are a few extra settings your application will require to ensure the network works correctly and Apple will approve your application. These requirements are not always obvious (some are documented, others are only implied in documentation). I thought I'd share them so that you can avoid network dropouts and unnecessary App Store rejections.

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StreamToMe is available for the iPad!

Apr 3, 2010 (an Objective-C era article)

StreamToMe is on the App Store for the iPad from day 1, so you can watch video and play music stored on your Mac using your iPad wherever you are.

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Streaming MP3/AAC audio again

Mar 29, 2010 (an Objective-C era article)

This week I present some further additions to AudioStreamer, a class I first presented in Streaming and playing an MP3 stream and revisited with bug fixes in Revisiting an old post: Streaming and playing an MP3 stream. This time, I'll add the two of the most requested features: seeking and HE-AAC audio support.

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Dynamic ivars: solving a fragile base class problem

Mar 22, 2010 (an Objective-C era article)

In the "modern" Objective-C runtime (that's iPhone OS or 64-bit Mac OS X), you can dynamically add ivars (instance variables) to a class without declaring them first. This allows a solution to the common "fragile base class" problem involving ivar layouts. Dynamic ivars can also help data hiding and abstraction and can even create a confusing situation where a base class and a sub class have ivars with the same names that don't refer to the same underlying data.

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