Plotting Widget Features

[ES-Alexander]

During inspections (and navigation) it can be helpful to see real-time plots of collected sensor data. A valuable plotting widget would include:

• ability to live-plot data from the vehicle
  • MAVLink data
  • other data (e.g. CPU load, network latency)
• multi-signal plots
  • multiple lines on one graph (e.g. two temperature readings)
• signal modifiers
  • maths operations (e.g. abs(roll), or depth+altitude for bathymetry)
  • display-modifiers (e.g. scatter point colour and/or size based on a different signal, like depth coloured by heading)
• text annotations (e.g. title, axis labels, legend, colourmap descriptors)
• axis scales and modifiers (e.g. log time scale to squish together old data to not scroll past it as fast, constant offset)
• axis limits settable to auto or fixed values
• option to choose between plotting variables against time or a different variable (like on an oscilloscope)

Some internal discussion here

[ES-Alexander]

This was also discussed somewhat in #449, as part of a standard widget version of the existing VeryGenericIndicator mini-widget.

A basic form of this that could still be very useful would just be a time-based plot of a single variable, with a settable duration (or number of data points?).