Forked controls or splines?

Just an outlier here wondering if geometry developers ever came up with a fully capable forked spline which can act as a control for NURBS or smooth objects or meshes. I have searched a bit but don’t quite see any examples. I realize that other solutions are offered to reduce cluttered definition but not the simple forking nature of rivers, trees, etc…

Hello - this sounds like a job for subdivision surfaces-


Thanks for your reply and the fascinating video on SubD in Rhino3d v7, especially the part pertaining to “Y” forks. This implementation of “Y” surfaces is increasingly useful for the state if the art.

However I was referring to a different conceptual 3d control system as yet not considered worthy of development, as one which might more exactly reproduce the veins of wood, or the layered tree rings, (which are cut through in board sawing). This might appear too complex for 3D CAD topology, yet it might also open the doors to the next level of manufacturing, and be found less problematic than expected for todays technologies.

In any case the challenge exists with applications for modeling real world solids and force fields as nature does, and it may advance product manufacturing, (in various ways such as mimicry of biological or mineralogical growth).

As a followup question, is there a “2d texture rendering type” in Rhino which can display surface lines, only in one direction by choice, which might reduces crowding lines as the 3d structure narrows? In this way we would avoid the solid coloring in lowered 2d graphic renditions.

Can you maybe make some sketches of what you are thinking of?
For something like layered tree rings you might want to look at isosurfaces (see the GH plugins Cocoon and Dendro, and this thread Metaballs to mesh in year 2020)
When you talk about surface lines in only one direction, do you mean showing only the u or only the v isocurves of a NURBS surface?

Thanks- I don’t have nature’s scientific examples as I’m referring to something possibly new, which gives a sense closer to primitive lines of force or growth… I do have a NURBS surface attempting to make a visual impact based on a real world inflated surface-

Note the crowded lines near the top of the NURBS. What seems desirable is the “same sized spacing effect” between lines or control lines; whereas most mesh types are centralized cells, and the principle of very long strip-like facets would emulate real tree growth.

PS- The point of the design above is that just one square sheet of plastic is used…