Help me create surface or thickness in parametric design pls

[flonako (lisya)]

hi can anyone help me? so im making a food cover with this parametric design and trying to add the hollow by using lunchbox plugging, but the result looks so complicated and the hollow is on every surfaces

i wanna change the model for only having one thickness or surface but still have the same design, my previous design is much more look like having a void or empty space inside each stack, not a thickness or one surface, so thats why the result looks so complex

this is how i wanted, only have one surface or thickness

this is what my model looks like, its like having a void in each stack

and is there any ways to create the hollow without lunchbox?

thank you so much for anyone who helps! id be so grateful t__t

heres my gh file
parametric.gh (26.5 KB)

[ftzuk]

Or do the design in grasshopper, bake it then offset in Rhino to create wall thickness.

cover.gh (25.2 KB)

[Joseph_Oster]

I’m not sure this is what you want? I’m out of time for the next ~3 hours.

steps_2025Apr29a.gh (20.7 KB)

P.S. There is a way to thicken this…?

P.P.S. Install Sunglasses instead of Bifocals!

[flonako (lisya)]

yup, this is exactly what i wanted! thank you so much, i really appreciate it

[ftzuk]

@Joseph_Oster

P.S. There is a way to thicken this…?

Wish GH would get a native thicken brep option.

[flonako (lisya)]

thank you so much!! this is the same like what i wanted!

[Joseph_Oster]

@ftzuk

Wish GH would get a native thicken brep option.

It’s complicated to get something that works with all geometries. It’s easy to see why this fails.

steps_2025Apr29b.gh (43.9 KB)

[Joseph_Oster]

I looked again at thickening the shape I created yesterday and found numerous problems.

Using a positive ‘Thickness’ value, Offset Surface (orange group) offsets IN instead of OUT. That’s not intuitive, even though IN is what I want. More seriously, IN creates self-intersecting surfaces in some cases, especially when the surface “diameter” (in top view) is small.

Offsetting OUT works fine but increases the shape size.

A cascade of issues is caused by this discovery. Code can be adapted but intervention earlier in the process looks necessary to me. Thickening IN or OUT must be an option, eh?

My inclination is to not even try because the “easy way” would be very specific to this geometry. So much depends on how a shape is created that a universal solution seems unlikely - from me.

[Joseph_Oster]

This is one of many “simple” ways to thicken this shape. Simple in the sense that it’s very specific to this geometry rather than trying to work for all shapes.

SUnion takes ~7 seconds (in R7) so a two second Data Dam was added before it. (red group)

steps_2025May1a.gh (35.2 KB)

[flonako (lisya)]

this is so interesting to learn and rlly helps me! once again thank you

[Joseph_Oster]

In another thread, Martin Siegrist (@martinsiegrist) posted a C# solution to thickening that is impressive I don’t think I’ve ever seen it before. It uses the CreateOffsetBrep method which has been hiding for years. With minimal refactoring I was able to get it to work in R7.

So to try it here, I modified earlier code from this thread to produce a simple stepped shape.

Then added Martin’s C#. At first, I got nothing but fiddled with the ‘tolerance’ value to get this:

steps_2025May18a.gh (28.8 KB)

I looks good but according to the text panel is an “Open Brep”, not a “Closed Brep”. I baked it and used Rhino’s ‘Analyze | Edge Tools | Show Edges’ feature:

to see this; pink curves show “Naked edges” that prevent it from being a “Closed Brep”.

It’s possible that changes before the orange group can fix this problem, such as rebuilding the ‘TweenCrvs’ or using fewer points or different seed values for random amplitudes’.

I don’t know why radiused edges appear on the outside of this shape?

[martinsiegrist]

@Joseph_Oster

C# solution

This script is from long ago and I think it’s by @Mahdiyar

Here’s a similar one in a recent post:

Fillet offset box corners

[image] private void RunScript(Brep brep, double d, ref object a) { a = Brep.CreateOffsetBrep(brep, d, true, true, true, RhinoDocument.ModelAbsoluteTolerance, out var _, out var _); } OffsetBrep.gh (11.0 KB) The Parakeet, Sasquatch, and Bubalus plugins each come with their own Offset Brep components that you can use.

[Joseph_Oster]

Very interesting. It appears to work best with “simple” shapes that have clean edge curves but I haven’t experimented with it much yet. Apparently sensitive to ‘tolerance’ value changes