GGX Anisotropy BRDF

[MatheusMarkies1]

Good Morning.
I am implementing a BRDF anisotropy model.
However it was strange.

GGX BRDF

 //Anisotropy Surfaces
float SpecularStrengthAnisotropy(Surface surface, BRDF brdf, Light light) {
    float at = max(brdf.roughness * (1.0 + surface.anisotropic), 0.001);
    float ab = max(brdf.roughness * (1.0 - surface.anisotropic), 0.001);
 
    float3 h = SafeNormalize(light.direction + surface.viewDirection);
    float NoH = dot(surface.normal, h);
    float ToH = dot(surface.tangent, h);
 
    float3 b = normalize(cross(surface.normal, surface.tangent));//normalize(cross(surface.normal, surface.tangent.xyz) * surface.tangent.w);
 
    float BoH = dot(b, h);
    float a2 = at * ab;
    float3 v = float3(ab * ToH, at * BoH, a2 * NoH);
    float v2 = dot(v, v);
    float w2 = a2 / v2;
    return a2 * w2 * w2 * (1.0 / PI);
}

Result

Where did I go wrong?
How can I fix this?

[Silence]

I don’t know this brdf, but this looks strange to me:

@MatheusMarkies1

`float v2 = dot(v, v);`