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Hi

I have made attempts to resolve this file, but everything has been useless.
If anyone can find it and explain to me how to do it, I would greatly appreciate it.
Greetings.

Attachments:
Patches.3dm

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Hi Booleano, can you describe a little bit about what you're trying to do?

Is it that you want to apply the 2D pattern onto the blank sphere and get a result like the soccer ball?

Is it ok if there is stretching or compression of your pattern?

Because it is not mathematically possible to apply a pattern like this without distortion especially around the "poles" of the sphere. For example you know how in a 2D map of the earth the size of Greenland is distorted.

If you want some polyhedral base 3D shape to build on top of you could load one of Rinus Roelofs' model files from here:
http://www.rhino3d.nl/pythposter/pyth3dm-eng.html

- Michael

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HI Booleano
这是制作足球的正确方法。（This is the correct method for making football.）
https://www.bilibili.com/video/BV1Yp421U762/?spm_id_from=333.999.0.0&vd_source=913e265b028433d7f4030496da189d83

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Hi Michael
This example is not mine, but I think it was done with the Flow function, but how?

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Esto es muy complicado, no se tu nombre, 这是制作足球的正确方法

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Seems you have not the good start plane surface!
you must have 2 sorts of geometric figures!

12 pentagons & 20 hexagons


So maybe for the flow take only the 12 pentagons! ;)
You will obtain directly the missing hexagons! ;)

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Hi Booleano

> This example is not mine, but I think it was done with the Flow function, but how?

The completed soccer ball here was not done with Flow, because doing Flow from a plane onto a sphere will have compression in the deformed objects at the "pole" areas of the sphere.

But you can construct a polyhedron from a flat pattern by using Transform > Rotate > "Rotate axis" along with some construction circles to snap onto.

The technique is shown in these previous discussion threads:
http://moi3d.com/forum/index.php?webtag=MOI&msg=2140.46
http://moi3d.com/forum/index.php?webtag=MOI&msg=911.11

- Michael

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HI Pilou

I'll try it as you say, let's see how it goes.
Thanks.

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Hi Michael

It's not the same, but it can be interesting.
Thanks.

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Hi Pilou

Sorry, this system doesn't work either.

Thanks.

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I don't tried it... i will see that!

Another thing: ask Show Points for see the radial "top poles"

Maybe you can trim them and remplace them by another same size meridian poles ! ;)

So maybe more suitable for the Flow! ;)

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Rotate the seam
Draw a square for trim the Poles N S
Boolean Merge or Trim for have 4 poles + middle surface
Kill North - South Poles
Copy rotate Left Right Poles
Join all = a solid sphere!
You must have a sphere with North South poles for use the Flow with more facility! ;)

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Not yet perfect but....



PS Another idea..
if resulting forms are deformed just draw the start forms with the "opposite" forms! ;)

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Hoi Pilou

Thank you

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My 2 cents.

MoI is not the easiest way to create this volume from scratch.
I think the easiest way is to use a software with a constraint resolver.
MoI don't have such feature.

You create pentagons and hexagons using same edge length.
Next, you add constraints to force your edges (or points) to be joined.

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Hi Pilou & Booleano - it isn't possible to apply a flat 2D plane onto a sphere without stretching or compression.

It's just a fundamental fact of geometry.

That's why Flow is not going to be the right tool for doing that.

Again, the technique that can be used for modeling a polyhedral shape is to draw polygons that have shared edges and then use Transform > Rotate > "Rotate axis" to pivot the polygons upward around the shared edge.

This is described and demonstrated in these previous posts:
http://moi3d.com/forum/index.php?webtag=MOI&msg=2140.46
http://moi3d.com/forum/index.php?webtag=MOI&msg=911.11

- Michael

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Hi Phiro,

re:
> I think the easiest way is to use a software with a constraint resolver.

A constraint solver isn't needed - you can just draw 2 vertically oriented circles that then intersect at the needed point for rotate axis to snap on to.

More details here:
http://moi3d.com/forum/index.php?webtag=MOI&msg=2140.46
http://moi3d.com/forum/index.php?webtag=MOI&msg=911.11

- Michael

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Yep but as adventure game that is perfect from time to time! :)
I don't desesperate to find a solution! :)

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Another strategy...

Make a sphere from Subdivision! :)



It's winning for Flow if exists a geometric division by 6 surfaces of the soccer ball!

PS Trivial question...
Why the subdivision surface still stay in 6 separate faces and not redone a normal sphere when join or union?

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Hi Pilou,

re:
> Why the subdivision surface still stay in 6 separate faces and not redone a normal sphere when join or union?

The subdivision surface sphere is not quite exactly spherical.

Since it is not an exact match for a sphere there isn't any mechanism to try and convert it into an exact sphere.

If you want an exact sphere, you can make one with the Draw solid > Sphere command, instead of using SubD conversion.

- Michael

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