Unity PointLight range and attenuation

UnityPointLight.hlsl

#include "AutoLight.cginc"
#if defined(POINT)
// 1/range*range for Unity's PointLight
float UnityPointLightRangeInvSqr()
{
    float3 unitLS = float3(unity_WorldToLight._m00, unity_WorldToLight._m01, unity_WorldToLight._m02);
    return dot(unitLS, unitLS);
}

// https://forum.unity.com/threads/light-dist ance-in-shader.509306/#post-3326818
float UnityPointLightAttenuation(float3 positionWS)
{
    float3 positionLS = mul(unity_WorldToLight, unityShadowCoord4(positionWS, 1)).xyz;
    float3 distanceLSSqr = dot(positionLS, positionLS);
    return saturate(1.0 / (1.0 + 25.0 * distanceLSSqr) * saturate((1 - sqrt(distanceLSSqr)) * 5.0));
}
#endif