Hello everyone. I’m wondering if anyone else in the community has found a solution to a simple SubD challenge:
“Create a rectangular hole with rounded corners within a SubD face.”
Essentially, I’m trying to create just a simple rectangular hole. I thought this would be straightforward, but it seems like rocket science—at least to me. The workflow I followed is the following:
Step 1. Isolate a SubD sub-geometry from a larger geometry where I want to create a simple rectangular hole with rounded corners (and ideally, fill it back with a removable panel if successful).
Step 2. Extract the quad face where I need to create the hole (the issue I’m experiencing happens regardless of whether I operate on the original SubD or just the extracted face).
Step 3. Get an isolated simple quad face.
Step 4. Create a tile with a topology that allows me to have rounded corners and add depth by extruding the edges (this topology isn’t necessarily ideal, but so far, it’s the only one allowing me to create a simple rectangular hole with rounded corners!).
Step 5. Insert the tile back into the original SubD.
Step 6. Join the original SubD and tile and hope for the miracle.
Result. Unfortunately, the miracle doesn’t happen. Although the result seems decent at first, zooming in reveals very strange geometry with self-intersecting edges. The issue is even more apparent when exporting to a NURBS.
Can anyone help, please? File is attached.
Many thanks!
also not sure why this is so tricky, i never quite played enough with subd in rhino, i had the feeling this process was a bit easier elsewhere, but then again since i switched to rhino 15 years ago i am more into nurbs.
Thanks for your suggestion. However, it doesn’t have rounded corners, but creases. Also, because this sub geometry is a part of a car, if I increase more subdivision on this panel, the geometry manipulation will result as quite complex everywhere else, when the aim is to get a few quads to get smother results and curvature. I find adding details in subD extremely labour intensive. Holo did get good results with his Ferrari Dino!
You can also try this method, that will prevent you from readjusting geometry somewhere else on the car. And yes I have no idea how to use SubD in Rhino…
Hi Tommy, just tried in Rhino SubD. This topology does give better smooth corners, but at the same time it creates a distortion in the adjacent geometry, where the triangular faces are now created.
if you know how to subd model in blender, you already know how to subd model in Rhino… Subd modeling is subd modeling… it’s simply a matter of translating a few tools in your head.
extruding, stitching, adding edges, inserting points, all the same as any other subd package, The most important thing is to learn topology and you clearly have that down.
yeah im just unfamiliar with the tools/name differences in rhino compared to other programs. I did notice a lack of any kind of knife tool, or maybe ive just missed it and how insert edge loop works slow. thats whats kept me from doing any subd in rhino.
