tools: add mapping option to map input vs output speed

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
tools: don't build the ptraccel debug tool if static libraries are disabled

We need access to a couple of non-exported functions

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
tools: convert gnuplot data to self-executable scripts

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
tools: print the unitless gain for pointer acceleration too

Unitless gain is simply speed(out)/speed(in), as used in [1].

[1] G. Casiez & N. Roussel. "No more bricolage! Methods and tools to
characterize, replicate and compare pointing transfer functions." In
Proceedings of UIST'11, p. 603-614, October 2011. ACM

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
tools: increase precision for ptraccel debug output

This matters a lot in the graphs, making the data points smoother and showing
the actual curves as well.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
tools: pass the step parameter into the speed mapping function

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
tools: make the "speed" mode the default for the ptraccel debug tool

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
tools: ptraccel-debug: change the sequence mode to be explicit

No more auto-detection.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>