vec3 T = normalize(vec3(model * vec4(tangent, 0.0)));
vec3 B = normalize(vec3(model * vec4(bitangent, 0.0)));
vec3 N = normalize(vec3(model * vec4(vNormal, 0.0)));
// convert TBN to world->tangent space
mat3 TBN = transpose(mat3(T, B, N));
vec3 T = normalize(vec3(model * vec4(tangent, 0.0)));
vec3 B = normalize(vec3(model * vec4(bitangent, 0.0)));
vec3 N = normalize(vec3(model * vec4(vNormal, 0.0)));
// convert TBN to world->tangent space
mat3 TBN = transpose(mat3(T, B, N));