rygorous

#include <complex>

static size_t const kMaxN = 2048; // This is the largest straight FFT we support

typedef std::complex<float> complexf; // or use whatever other complex number type you prefer

// This is a "mip chain" of precomputed twiddle factors
// Twiddles for length-1 start at index 1,
// twiddles for length-2 start at index 2,
// ...,