Map StandardMaterial3D to vertex shader mesh

Godot Version

4.2

Question

I’m totally new with 3D game engine, still exploring the overall concepts (very exciting!), apologies if the question lacks relevance.

I’m building a landscape made of a plane subdivided mesh, whose vertices get modified by spatial shader.
On principle I would like to apply combination of a large scale height map (terrain) together with a detailed and repeating material (sand texture).

1/ I tried adding a StandardMaterial3D to the “next pass” material on top of the shader, but whatever the priority given this material gets mapped to the original plane mesh, not the one resulting from the shader.

2/ I did not find in the documentation of forums any method enabling to export the resulting VECTOR matrix so I can import it back as a static mesh and apply the StandardMaterial3D to it.

3/ I’m wondering if the only (or best) way is simply to combine everything in one single spatial shader, meaning inject roughness, normal map, ambiant occlusion, etc … I just wanted not to reinvent the wheel.