Parametric texturing a Polysurface / Brep from CAD Part in Grasshopper

I want to texture surfaces from an imported Solidworks body and need some general guidance on how to best approach it.
I am thinking on exploding the body to separate out the wanted surfaces, bring them into grasshopper, do my modification,
bake them and rejoin the surface with the rest of the CAD Body to result in a watertight manifold.

The first picture shows how a potential structure could look like (this is done with mesh in Blender). If I can avoid it I would prefer to stay
in Nurbs, because I fear that when I convert to mesh I loose some precision on Places where it counts (currently not in the model) and I assume
I cant work with half a mesh and half a Nurbs body and export this watertight/joined for 3D Printing?

For me it is critical that the transition between the textured (2nd pic, marked yellow) and untextured surfaces stays how it is right now (G3 torsion continues acc. to Solidworks)
And that the texture fades to 0 extrusion height when it reaches the boundary edge.

One approach I was thinking about was, that I somehow try to recreate the surface I want to texture in Grasshopper, this would give me access to points and curves which I could manipulate
in the normal direction height, adding extra points, using attractors, noise, random numbers aso. to construct ridges and valleys of the textures and then build the surface from points, so far without success. Also because a simple ‘divide surface’ to get points does not work for 4 combined surfaces since they have different UVs, rebuilding the polysurface as 1 surface in rhino was not successful.

The 2nd Idea, is something according to this blog post (Landforms created through Topological Analysis of Shapes – Example 4.7 | Generative Landscapes), to construct nurbs objects which are later combined with the original surface
I think it is the way to go, since i could stay in nurbs/brep, the only problem I have is that I am missing the generative nature of finding
shapes, since they are constructed and positioned by me.

The 3ed approach would be generating a texture in Blender (generative, first picture) and from this a height map and then somehow trying to displace (a mesh?) in rhino. I tried the same approach in solidworks, which was of bad Quality at the transition zone because of mapping issues and the step marked in blue on the first picture. I guess I could get rid of the step in Blender.

I was also thinking on creating kind of a Die from the texture and then boolean the structure out of my part in SW or Rhino

Any Ideas on how to best tackle this would be appreciated?

I added a file where the CAD body is included and I played with piping along voronoi and voronoi extrusion acc. to this post What would be the best way to patch this? - Grasshopper - McNeel Forum


surface_texturing.3dm (930.4 KB) (495.6 KB)

I would just like to know what pattern do you want, but you just didn’t say that. After telling us this much, you just omit that one most important part…

I don’t know if this will help you or not, but I did this by morphing a rectangular array of hexagon shapes on to a cylinder. Each hexagon had the same 3D Truchet curve on it, but that could be replaced by whatever shape you wanted.

A problem with my method is a vertical seam that is hard to see, but it is there nevertheless.

Sorry if I couldn’t make it clear. The pattern can be seen in the 1st. Picture… This would be the optimum, it is generated in Blender, the components are a vornoi texture which is distorted with a noise texture . So far I can create a vornoi texture acc. To the linked post above, but this is not the question here, its more about the constrains mentioned in the post (fading extrusions to zero, close to the edge, keeping curvature constraints of transitional surface) and a possible workflow, as mentioned above, staying in nurbs, converting to mesh, distorting mesh with height map from the blender texture, recreating the yellow colored surface in rhino to have access to UV points which can later be manipulated eg populate geometry - > vornoi cells from points - > extrude vornoi cells along normal - > cut extrusion with spheres or lofting? etc… aso…

Thank you for your reply… I am going to try that out…

It must be my English. I have no idea what pattern you want other than keeping G2 at the transition part.
Show some pictures?

Try using boundary as an attractor, moving control points but keep those near the edge static.