This patch contains a new keyboard view with an adjustable layout.
As of this version, it draws and displays notes from the MIDI keyboard
but doesn't handle any of its own touch events.
This patch implements nonlinear distortion in the resonant ladder
filter. It's based on the differential equations in the Huovilainen '04
DAFx paper, but using matrix exponential to compute the evolution of the
state variables. The implementation is scalar (and calls into sqrtf),
but designed to be implemented in very efficient SIMD.
Add a button to capture raw start and end callback time (just putting it
in a text buffer so it can be copied), which is useful for making plots.
Also a bunch of commented out code to provoke priority inversion or
sudden increases in load (which exercises the governor), again for the
purpose of probing performance and making plots.
This change adds a (single) resonant filter to the C++ synth unit, and
wires up both USB MIDI and on-screen controls for cutoff and resonance.
Also fixes a bug in KnobView which caused the knob value to jump around.
Raph Levien
Bryan Klimt