Polygonal rounded

Hello Lads!

I have a good one. Some time ago I asked exactly the same question and somebody came up with the solution, but I just can’t find the post. I am trying to generate this shape with grasshopper to make it completely customizable. Is there a way that I can find all the posts I’ve made since I register? Or can somebody give me a hand on how to generate this kind of shape? It is basically creating a polygon and the generating an arc in between each of the vertices. I just want to make an experiment for making a wooden bracelet. after generating the shape I will extrude it and making the bolean difference I just don’t know how to create it. I know that it was not really difficult to make but I just can’t remember how it was.

Thanks in advance!

Through your profile the activity section

Hey Jester!

Yes I tried. But, it just shows the post of the last month. I might have asked about this topic 2 years ago or so, so I don’t know why it is not in my activity :S. But thanks for your help :slight_smile:

With this user profile you have created two topics. Your profile exists since February 4th, 2018.

You probably need to try to remember what your username was prior to that. Oh, and that may have been on the old grasshopper3d.com forum

you want a squircle, I did just for fun this definition but there must be more elegant solutions out there :slight_smile:

shoftgon.gh (14.2 KB)

It defenitely was in the old grasshopper forum. But thanks again

Thanks Aris!
You rock! I’ll check it out! and try to make it! This is what I made a few years back as a present and I want to make it with grasshopper now, just as an exercise.

I think you don’t want a squircle, just a rounded square.
I was trying to do the squircle mathematically when I saw your pictures.
The two shapes look alike but I think a rounded square (cyan) fits your purposes better.

squircle.gh (19.2 KB)

Hey again Aris,
Actually the squircle its OK, as one of the things I wanted to add is kind of “inflate” the square. I want to create an arc in between each vertices and then round that intersections. One thing is that when I bake it makes a lot of points, which is fine, but I don’t know what will happen when I create the surface.

Now I am triying to create an offset and move in Z to then make a loft of those 2 geometries, but for some reason it’s not moving it in Z. I migth be doing something wrong but I’ll Keep trying :slight_smile:

Sorry, It’s this what Im doing but for some reason is not making the loft

cannot upload files right now, but the many points are due to pointiness/samples which makes a dense curve. try using rebuild curve to simplify it.

for offseting in z, use extrude. offseting only offsets a curve on its plane.
cannot help you anymore today… going to the beach!!! :joy:

Thanks Aris!

No worries! enjoy! This is an on going project I’ll keep you updated :slight_smile:

This is the fastest way I can think of, though I don’t know how to set control point weight in grasshopper :frowning:

When looking at your image, the idea of using Tween Curvecomes to mind.

Tween Bowl_re.gh (13.2 KB)


Thanks Ivelyn,
I actually know how to make it in rhino but I’m trying to make it customizable and easy to change in grasshopper.

Thanks Kim! This looks awesome!

I’m trying something else and this is how far I am.

I’m basically creating a Polygon and dividing the curve in the number of segments that the polygon has. Next step is to make an arc from each of the vertices, f.ex. From vertice A to B, B to C, and so on (which I don’t know how to do). I don’t know if it makes any sense or if it is possible to do it this way. Any ideas?

Why manually construct arcs? Use fillet like @HS_Kim
And if you are looking for a shape that has a slight bulge with the arcs you can check out Pufferfish’s Prude Curve component.

Prude.gh (6.3 KB)

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Geez, I made my name with all caps cuz people keep putting “y” instead of “i”. :face_with_symbols_over_mouth:

Thanks Michael! This is actually super cool!
But how can I control the diameter of the shapes. f/ex. This is for making a bracelet, so if I want the exterior shape to be circumscribed in maximum diameter of 100 millimiters and the interior one on 70 mm. how can I control that? As I understand in this code you can control the length of the curve, which generates very cool shapes for a bracelet like these ones:

But you cannot control the number vertices or diameter/redius of the polygon.

Sorry for that IVELIN.