The important for me is to not unpack normal in the 2d texture node, as long as it is separated process, your DeriveNormalZ should achieve the same result.

There is an example of what I did before, I have a height map as sampler, then I procedurally calculated the height into vector, converted into normal map. At the last bit, I shuffled the channels, then used unpack normal node, so it will calculate Z correctly.

I managed to get the screen space between 0 -1, however, I get this distortion, if my camera isn't look straight to the plane.

Is there a work around ?

Thanks, cool. Can you should me how Fresnel works, I would expect to have input for view direction, and normal, and power by a value to get a fall off, your node has normal and exp, two input. can't seem to get it work.

Would Fresnel node take consideration of the deformation ?

Great, I meant the one in the inspector. Thanks.