Reply To: Some weird artefacting on dunes

Hello incredulous, this is probably due to the fact that this is a preview, which has a subdivision rate of 8 pixels. 

If you want, you can change the Dicing Rate here:

Or just try a real render;)

One more note: normally you should change the Math > Multiply Node to a Vector > Displacement Node to get a correct Displacement!

In this case, you might want to leave it like it is, because otherwise you will need something like a Vector > Vector Curves Node

between the Mix and the Voronoi to get the dune shape…But it would be the better way to do this.

See also Kent’s Shader Forge > Bodies of water where he controls the Voronoi in a similar way.