The major problem with creating such a tiny square of terrain are:
- Viewports: At very small and very large scale, a lot of assumptions built into the viewport (such as navigation, z-range, and so on) are violated.
- Defaults: Most device settings assume a much larger world, so the parameter sliders become ungainly. For example, the Basic Noise device will accept a very tiny value, but the smallest slider increment is 100m - pretty problematic when your entire world is 10m! You can directly enter a small value, but that’s slower…
In terms of the actual algorithms, they don’t care at all, and you can produce tiny output if you wish - it’s just painful ergonomically.
An easier solution is to work scaled. So for example, if you want a 10m x 10m x 10m world, instead make it 1km x 1km x 1km. Every value will be reported 100x larger than you want, but it will be MUCH easier to edit within WM. If you are exporting as a heightfield, the scale within WM doesn’t matter anyways (the output is just an image with no intrinsic scale), so there will be no difference there.