This is mostly just a little wrapper around paul's teensy audio library synth_wavetable, updated to make sure it runs on the ATSAMD51 with adafruit's atsamd fork of Audio.
decoder.py here is taken the teensy AudioSynthWaveform repo, with changes to make it output parsed soundfonts in the format expressed in the
synth_wavetable.cpp file from the Audio repo
if you run decoder on a soundfont, it'll drop the headers in src/instruments. then you can edit
instrument.h and change these lines:
#include "instruments/AnalogSaw_samples.h" auto instrument = AnalogSaw;
to, for instance,
#include "instruments/lead_samples.h" auto instrument = lead;
and that'll be your instrument now.