Seashore interface adaptations for SmartNav
Screen captures from one of today’s projects, adapting Seashore for easier use with a SmartNav head-mounted mouse. Seashore is a free software Macintosh derivative of the GNU Image Manipulation Program. Since Seashore uses nib files for its interface resources, it’s a piece of cake to open up Interface Builder and resize, realign, remove, and re-bind keyboard shortcuts for user interface elements throughout the application. Here’s a simple example, options for the paintbrush tool:

(A full-size version of this image.)
The original, on the left, uses small control sizes and presents options for a pressure-sensitive devices. The modified version, on the right, uses regular control sizes, and we’ve added tick marks to the slider and hidden controls irrelevant to the human interface devices we happen to be working with. These are small changes, but it’s enough of a difference to make a difference.
Slider controls are tricky because they ask you to first move a tiny target over a continuous range and then stop moving it in order to make a precise selection. In almost all cases, we’ve turned on between 8 and 12 markers, and checked Stop on tick marks only so that sliders snap to markers. You lose a lot of precision that way, but this doesn’t matter if you’ve chosen a strategic number of markers. This approach for slider controls is inspired by the way a similar user interface element responds to stylus or finger control in Animal Crossing.

