Add support for swipe gestures from lpm state

Overall the difference probably does not matter, but I'm used to doing it this way because...

What we want to do is to divide "half width" into "small step" + "large step".

Doing: Sl = half_width - Ss ---> guarantees: Sl + Ss == half_width

But due to integer divisions: half_width*1/10 + half_width*4/10 does not necessarily equal half_width.