musicmouse/espmusicmouse/lib/ledtl/helpers/BellCurve.h

19 lines
371 B
C++

#pragma once
#include <cstdint>
static inline float bellCurveApproximation(float x, float inverseWidth)
{
if (x < 0)
x = -x;
const auto nx = x * inverseWidth * 4;
if (nx > 2)
return 0.0f;
const auto x2 = nx * nx;
const auto x3 = x2 * nx;
const auto res = 1.0f + 0.27606958941084f * x3 - 0.80213917882168f * x2;
return res < 0.0f ? 0.0f : res;
}