WIP: dasher integration

[nelljerram]

Dasher is a method of text entry that works by moving a cursor over a field of possible next letters that appear from the right hand edge of Dasher's window and move to the left. It incorporates language-dependent probabilities so that it's easier to select the more likely next letters, but it also remains possible to select any sequence of next letters.

I believe it's used quite widely by people who can't use normal keyboards, and there are various approaches to controlling the cursor position, including buttons, eye tracking and tilt.

In the context of Linux phones, I'm interested in the tilt approach, with

• left / right tilt controlling how quickly the cursor moves to the right (or, more correctly, the possible next letters move to the left)
• down / up tilt controlling which of the possible next letters is selected.

Please see also the Dasher home page at https://www.inference.org.uk/dasher/