[tslib] 25 points tslib linearization

[Rubens Diniz]

Hello all,

First of all, congratulations about tslib jobs, really a excellent lib.
My name is Rubens from Brazil and my hobby is build machine using
software and hardware interface with preference with touch screen as
control.
On Brazil i have a brewery and made a touch panel to control all brew process.
This system are using a eGalax compatible 15.6 inches monitor and
raspberry pi 3.

My problem is, as im using a cheap available resistive touch screen
monitor, calibration using 4/5 points is not enough because monitor
don´t give me linearity. I need make a linearization with 25 points or
more to get accuracy touch.

If this problem will be resolved, there is no more limits for
applications using raspberry and big touchscreens.

Can you help me about how can i resolve this problem ?

Best Regards for all.

Rubens Diniz