# Naturalistic to Geometric Stone

Hello Everyone-

I’m looking for a way to model “naturalistic” rocks that transition into cut stone. Somewhat like this photo here:

I tried a number of different strategies for the rough rock, based on these resources:
Using Simplex Noise: https://discourse.mcneel.com/t/stone-wall/82036
Using Image Sampling: https://www.grasshopper3d.com/forum/topics/how-to-make-stone-surface-into-grasshoper
Using a Cellular approach: https://www.grasshopper3d.com/forum/topics/rocks
I think out of those the simplex noise is closest to what I’m after. I want it to hint at looking realistic, but can add textures later in VRay or Photoshop. For the blocks themselves I have tried both using a grid with an attractor point and using panels from lunchbox.

In short, I am trying to figure out a smart way to parametrically and seamlessly transition from a noisy object to smooth blocks.

I want to be able to:
A) Make the transition from rough rock to multiple blocks, as if the blocks were being carved out of the stone
B) I want to be able to control the number of blocks and scale
C) I want to be able to control the transition point from rough to smooth and adjust the “tween” to make it a wider or more abrupt area of transition.

If anyone has any suggestions it would be super helpful- even things like plugins or links to forum posts that may be relevant. Thank you.

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A wide subject area. Per the example in your photo, look like the stone has about 150-200 years of weathering after cutting. So, you model your 3-d surface, then subtract cubic volumes out of it. After that, you will need to apply ‘weathering’ effects to the cut surfaces. One way is to model some random joint spacing in the rock (if you look at the weathered plane on the left side of the photo, you can see weathered cracks; if you loo at the cut corers that are chipped, you will notice that the cracking on the corners is about the same spacing as the weathered joints; the reason for this is that the natural rock has about the same natural joint spacing; hard to tell scale in the photo, but I suspect the joint spacing is between 3 to 5",
Good luck with your project; it is a deceptively simple problem in appearance.