Complicated description of quite a simple phenomenon:
When you map a texture such as a ramp or a grid to a surface, it is glued to that surface whatever you do with the surface. However, when you use a 3D texture such as marble, it kind of penetrates the whole surface, and when you move the surface, the texture seems to float through it.
3D Textures have a great advantage over others. For example the marble structure distributes over the surface of a polygon cube as if the whole block was made of marble.
Finally I answer the question: Can we use a 2D texture for a (floating) 3D texture experience? Yes, we can! We need to visit the Hypershade window and work with a projection utility.
The thumbnail shows the 2D texture at the back and the 3D projection of the same texture in front. Rendered with only one light in Arnold.
I composed the music intro (“Computer Animation”) and extro (“Dubius 170”) for this channel. It’s licensed via GEMA.