Add option to set default selection to other than the first about tofi

[philj56]

Hey, sorry for the slow response, been busy with work recently.

Is there a way to calculate num_results_drawn without actually rendering the text?

Not with the current way things are done unfortunately. Tofi is designed to start up as fast as possible, and quite a few shortcuts are taken to achieve that (especially for the first two frames).

The whole problem of auto-detecting how many results to draw is a tough one. In vertical mode it's fine — you can just divide the space available by the size of each entry, as they're all the same height. In horizontal mode, the only way to know how many results will be drawn is to draw (or at least shape) them all. This is kind of the crux of the issues behind #21 and #73.

I think it might be possible to solve this if the shaping and drawing were split up, so you'd shape all the text, measure that, do any shifting necessary, and finally render all the text. That'd be a pretty significant overhaul of how tofi handles drawing though, so it's unlikely to happen in the near future. I'll try and look into it at some point though.

Thanks for the suggestion!