installation:

• python setup.py install --user
• for PWM you have to set that up, see Servo.py
• then you also need pigpio running: sudo pigpiod

to do drawing:

• path optimization
• add more filters and find good balance
• semantics

bugs?:

• waveforms pause in between segments, especially large ones?
• think through the range signs and types wrt scaling

to do controls:

• move to pigpio and use a global pi() instace
• consider using edge event detection for the limit switches, but that part of the gpio lib doesn't seem entirely stable
• small plotter: pre-load waveforms onto the motors to improve performance? use threading timers somehow?
• big plotter: polarograph subclass to Trajectory