Plugin showing filament usage in-print

Does anyone know of a plugin that shows either or both of A) the amount of filament used in the current print (real time), or B) the remaining amount of filament required to complete the print?

It would be good to have real-time data during the print, and I wouldn't think it would be that hard to calculate and display. I have a filament runout sensor, etc, but when I'm watching a spool get low and wondering if I have enough on the roll to finish the print, I'd like to be able to see how much filament length or volume would be required to finish the print.