I have OS X with Preview and OmniGraffle. In both of these apps, resizing an image to make it larger results in heavy anti-aliasing. I want just big pixels. How can I get that effect instead of the anti-aliasing?
Pixen from the Open Sword Group is a pixel editor that fulfils your requirements. It is free (donationware), and comes in at 867 kb.
You can zoom using Mac OS X's integrated zoom functionality (usually
I can configure it in System Preferences » Trackpad on my Macbook Pro. It has the option to disable/enable image smoothing, and you can toggle any time by pressing
Screenshots created while zooming are zoomed. Unmodified rectangle selection screenshot: