How to add support for normal maps in PlaneGrid shader?

Hi!

I need to assign a shader that supports normal maps to the PlanGrid material in the HelloAR scene example.

The problem is, every other shader I assign to this material is rendered with an average color calculated by the colors on the assigned texture and moreover I don't know how to modify the original PlaneGrid shader to support normal maps.

Does anyone know how to add normal map support to the PlaneGrid shader or maybe use another valid shader for the generated plane?

Thanks in advance and have a nice day!