Shadery05_HueShift02

half3 HueShift02(half3 c, half shift)
{
    half angle = radians(shift);
    half cosAngle = cos(angle);
    float3 k = float3(0.57735, 0.57735, 0.57735);
    return  c * cosAngle +
            cross(k, c) * sin(angle) +
            k * dot(k, c) * (1 - cosAngle);
}