Generate normal from vertex paint layers to get depth variation

Hello, iam working on a plaster wall with different layers using vertex paint with height lerp what i want is how i can get a depth variation between the different Layers …similar to this thread Generate normal from vertex paint?here but unfortunately i didn’t understand how i can generate a normal map from My Height lerp Could any one Please explain how i cant a result similar to that … thanks in advance

here is my MAT

i also need help with this…