Indeed. And with a keyboard like this[1], the gaps between keys are smaller than (my) finger width, so a sliding finger might provide continuous data. Optical

Indeed. And with a keyboard like this[1], the gaps between keys are smaller than (my) finger width, so a sliding finger might provide continuous data. Optical position tracking of fingers was actually ok (but not on a bus, and not so much for stylus), and with a look-along-the-keyboard-surface mirror, even optical height and touch was ok. But the touch wasn't great, and occlusion was a "keep it always in mind" problem. So I would have been delighted to find say a low-precision multitouch textile, to hopefully drape over the keys without too-much impairing typing. To decouple a fast low-precision-XY high-precision-Z touch, from simple and adequate camera XY. But crafting a capacitive grid... seemed a yak too far. All this was yak shaving - I actually wanted to be exploring VR IDEs catalyzing improved programming languages. :/ [1] https://upload.wikimedia.org/wikipedia/commons/c/ca/ThinkPad_X1_Carbon_Japanese_Keyboard.jpg https://upload.wikimedia.org/wikipedia/commons/c/ca/ThinkPad...