[spam][crazy][random] Rotary Encoder: Slightly More Productive Goal

[Undiscussed Horrific Abuse, One Victim of Many]

As I try to move from goals that are intentionally pointless to those
that have some utility, I now want to resume my project of providing a
way to build a free high quality servo. Servos are motors that can go
to a specific orientation and optionally measure their orientation
and/or applied force.

Where I'm at, is I want to make a script that generates a printout to
make a rotary encoder. Servos usually use potentiometers, which are
inaccurate. Rotary encoders can be more precise.

Unfortunately, I've misplaced or lost my existing work. But the
subgoal is quite simple:

A script that generates an wheel of color according to a provided
radial function.

I think if the darkness of the bands on the wheels increases linearly
as a function of angle, the encoder could be calibrated to measure
possibly-arbitrary precision via a photocell facing the rotary
encoder.