uint32_t phase = 0;
int32_t state = 0;

int32_t f;
int32_t pitch = inlet_pitch + param_pitch;
int32_t shape = __SSAT(inlet_shape + param_shape, 28);
int32_t filter = (1 << 27) - __USAT(inlet_soften + param_soften, 27);

MTOFEXTENDED(inlet_pitch + param_pitch, f);

// calculating feedback coefficients in order to reduce aliasing and
// instabilities
int32_t shape_abs = shape > 0 ? shape : -shape;
int32_t parabola =
    ___SMMLA(shape_abs << 2, shape_abs << 3, (1 << 27) - shape_abs);
parabola = ___SMMUL(parabola << 2, parabola << 3);

uint32_t modamt =
    ___SMMUL((1 << 27) - (pitch > 0 ? pitch : 0) << 2, parabola << 3);
modamt = ___SMMUL(modamt << 3, filter << 2);

phase += f;

int32_t sine_mod = sine2t[((1 << 24) + ___SMMUL(phase, shape) >> 15) &
                          0XFFF]; // amplitude modulation signal (cosine)
int32_t a_per_b = ___SMMUL(state, sine_mod); // amplitude modulated feedback
int32_t phase_mod = ___SMMUL(modamt, a_per_b)
                    << 5; // phase modulation signal to put inside "carrier"

state = sine2t[(phase + phase_mod >> 20) & 0XFFF]; // magic happens here

outlet_out = state >> 4;

// the basic idea was:
// y(t) = sin(wt + A*y(t)*cos(w(t))
// (you can put it in wolfram alpha and see what it does! just set w to some
// value and A to 1, in my object A is set to fix aliasing and instabilities,
// and it's set in k-rate