How to transform normal map from tangent space to world space using Unity Shader Graph?

Question

I'm creating a custom lighting shader using the Unity Shader Graph and I want to add support for normal maps. I've read a bit and from what I understand I need to transform my normal map from tangent space to world space. I've watched this video , where around 8:00 mark there is a formula for calculating this: Red * Tangent + Green * Bitangent + Blue * Normal . I've tried to recreate it like this:

And here is how the normal is read:

This issue is that it doesn't seem to work. The normals are correct only if the object has no rotation (look at the position of the reflections):

However if I rotate it upside down the lighting is also upside down:

What am I doing wrong?

Answer 1

If you want to translate a vector from tangent to world space, you could use the Transform Node: