I recently spent two weeks converting JustLooking, my Mac OS X Image Viewing program, from NSImage to CoreImage and friends. This experience was overall much easier than I expected, and I have learned a bunch of things, some of which might have been handy to have known in advance.

The good news is that it mostly lives up to the hype. The bad news is that it’s not without tricks and traps of its own. Here are some notes and comments.

The Setup

Imagine, if you will, the following scenario:

• You design a whole new database schema for your cool new scalable web-application. You’re using MySQL and the InnoDB datbase engine for everything, because your schema is so cool it uses all sorts of foreign keys and transactions and the like.
• You quickly set up MySQL and get your application going with your new schema on your development staging machine.
• You get MySQL up and running on your live server, play around with it for a bit to make sure it’s working, and then set up a my.cnf file with all sorts of caching and security goodies in it.
• You do a backup from your dev machine, restore it to the live server, and ta-daa!!! Your web application is up and running on your live server.

What you might not have noticed, especially if you – like me – have a few thousands rows of data, is that MySQL might have screwed you along the way and not really told you all that clearly.

For a recent project written in Cocoa for Mac OS X, I found myself wanting to get the following set of information for a particular printer:

• A list of all available paper types
• Printable names for these paper types
• Page Sizes
• Imageable Margins for those same pages.

It turns out that there is no way to get this in Cocoa, and actually it’s not all that easy to find this information in Carbon either.

So, after some research and investimigation on the Intarwebs, as well as much combing through the various PM* header files (buried so deep in a directory on my machine that I had to save the directory name somewhere so I’d be able to find them again!), I’ve come up with the following method to do all the above.