Function fmod_inv

engine/dlib/src/basis/encoder/cppspmd_math.h:24–28

// I compared each to the ones in DirectXMath and stdlib's for accuracy/performance.

CPPSPMD_FORCE_INLINE vfloat fmod_inv(const vfloat& a, const vfloat& b, const vfloat& b_inv) 
{ 
	vfloat c = frac(abs(a * b_inv)) * abs(b); 
	return spmd_ternaryf(a < 0, -c, c); 
}

CPPSPMD_FORCE_INLINE vfloat fmod_inv_p(const vfloat& a, const vfloat& b, const vfloat& b_inv) 
{