Apply pattern to this shape

Hello all, So I have asked this question before, in one type of iteration or another, but here it is again, specifically with a specific example! I appeal to the Grasshopper Gods. Help!

I want to apply a pattern to the insert picture (the geometry “inside” the alcove. How would I go do that? It is a polysurface obviously. Do I actually have to sweep and remake that? I suppose maybe not the end of the world. But how else is this done? Thanks!Casdddpture

Oops here is the image. It is a complicated Polysurface, basically to complicated for me to rebuild in Rhino to create a single surface type deal.

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Fixed forgot to upload image…:hushed::open_mouth:

I would rebuild the geometry you want to pattern as close as possible as a single surface approximation in place. Make the pattern on that surface, then get the points of the pattern and pull them to the polysurface with something like pull point and re interpolate the pattern curves.

@blazetron420 (<-- :grin:)

…maybe with more specificity you can get answers with a possible work-around?

Is the pattern directly on top of the depressed region, as in just a bounding rectangle around it? You could get away with designing your pattern flat, perpendicular to the region you want to project it to.

…just suggesting based on the assumption you’ll end up making curves or cutting holes and stuff like that, which could mean skipping rebuilding and simply getting your pattern on the object.

Yes I suppose that would be the best option if its simply cutting holes out of a surface or what not (project the curves onto the surface. I guess in a production setting, with enough time, one could theoretically rebuild this shape exactly as is, as a single surface through a lot of work? Is that how that would work, say in a car company?

Always been curious about this, in “class A” modelling, are the surfaces perfectly flat?

Hi - the surfaces are definitely not perfectly flat, no. (Unless the designer wants them to be flat).
It is also not about making something as a single surface - almost the opposite because that single surface would end up being very complex. Use simple surfaces so that you have enough control over transitions to other surfaces.

There are many discussions on Class A here on Discourse - here’s one of those:

Actually, at Volkswagen there is a unwritten rule, that any visible surface has to be curved. Even if its crowned a little tenth of a mm only. Flat surfaces are bad in design, because they appear to be “pushed in”.
Also if you curvature-match a strongly curved surface (f.e. g2 fillets) to a flat surface, the blend always appears a bit odd in the reflection. So to speak, the opposite is true for class A when it comes to the technical criterias of class A: Always use curved surfaces! Single curved surfaces (also known as developable surfaces) are partially allowed in class A, under very rare circumstances.
But as said, class A is also more about iterative and long development under very harsh criterias. Rhino and especially Grasshopper has its limitations here, although its in theory possible to create class A models. Usually software used for class A are Icem Surf and Autodesk Alias, where Icem Surf is still the leading software in this very specialised field of engineering. And yes, its more about engineering, then design. Class A is a design refinement up to a production state.

See this for basic understanding:

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Recently completed a product where two of the parts are joined in sort of a ‘T’ fashion. At the juncture of the two, due to modeling laziness (or expediency), about a mm or two of the joint area was flat all the way around one element of the junction. (And it was not flat for mechanical or production purposes.)

That flat mm stood out like a sore thumb in the first prints and had to be fixed! And it was a royal PITA to crown that little spot post-process, though a ‘crime’ to build a big costly tool with the visual design flaw.

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