Anisotropic IBL

anisotropic_ibl.glsl

    vec3  anisotropyDirection = pixel.anisotropy >= 0.0 ? pixel.anisotropicB : pixel.anisotropicT;
    vec3  anisotropicTangent  = cross(anisotropyDirection, shading_view);
    vec3  anisotropicNormal   = cross(anisotropicTangent, anisotropyDirection);
    float bendFactor          = abs(pixel.anisotropy) * saturate(5.0 * pixel.roughness);
    vec3  bentNormal          = normalize(mix(shading_normal, anisotropicNormal, bendFactor));

    vec3 r = reflect(-shading_view, bentNormal);