# TheSwamp

## Code Red => AutoLISP (Vanilla / Visual) => Topic started by: well20152016 on April 06, 2019, 10:56:09 PM

Title: Algorithm: Draw ball
Post by: well20152016 on April 06, 2019, 10:56:09 PM
Known: 1. Radius of the sphere
2. Side Length of Hexagon or Pentagon (Approximate Value)
Title: Re: Algorithm: Draw ball
Post by: ribarm on April 07, 2019, 12:26:24 AM
If you want lisp, you should firstly analyze construction - it's called truncated icosahedron...
Here is my video with construction :

HTH., M.R.
Title: Re: Algorithm: Draw ball
Post by: well20152016 on April 07, 2019, 10:03:49 AM

Thank you! It's just a situation! I wonder if LISP can handle more situations?
Title: Re: Algorithm: Draw ball
Post by: BIGAL on April 07, 2019, 09:11:30 PM
If you can work out the maths then theorecticaly anything is possible. There is a mathmatical theorem for the soccer ball.
Title: Re: Algorithm: Draw ball
Post by: well20152016 on April 08, 2019, 01:05:15 AM
The surface of a football ball ball ball is a sphere made up of 12 regular pentagons and 20 regular hexagons.
Title: Re: Algorithm: Draw ball
Post by: well20152016 on April 09, 2019, 05:50:05 AM
dwg
Title: Re: Algorithm: Draw ball
Post by: ribarm on April 09, 2019, 09:39:17 AM
You generated different ball then I was expecting... It's not based on truncated icosahedron... I tried to get 3DSOLID, but some lines aren't touching exactly with each others and beside all this, to make 3DSOLID those lines have to make exact planar polygons - sorry it was close - my routine recognized some polygons and converted them to regions, but major of them were not processed, so final surfsculpt was not good...
Title: Re: Algorithm: Draw ball
Post by: ribarm on April 10, 2019, 10:19:22 AM

It's sphere constructed of 12 regular pentagons and 60 irregular hexagons... There are variants with 12 pentagons and 200 hexagons and 12 pentagons and 620 hexagons... Pentagon centers are positioned always at vertices of corresponding regular icosahedron...
Title: Re: Algorithm: Draw ball
Post by: ribarm on April 10, 2019, 10:38:12 AM
There is also this picture - extended dodecahedra...
Title: Re: Algorithm: Draw ball
Post by: well20152016 on April 10, 2019, 06:18:37 PM
Thank you. I'm studying, too.
Title: Re: Algorithm: Draw ball
Post by: well20152016 on April 12, 2019, 09:34:51 AM
It's sphere constructed of 11 regular pentagons and 80 irregular hexagons.
Title: Re: Algorithm: Draw ball
Post by: ribarm on April 12, 2019, 10:33:18 AM
Well it's almost the same as your first example... I would say 12 regular pentagons and 80 irregular hexagons... I guess I counted wrong - thought 60 hexagons... But the same - no success in converting 3d lines to 3d solid... Only pentagons were good, but then again I think that not all were processed - not even single hexagon is good - you have to check their planar characteristics... Still not perfect...
Title: Re: Algorithm: Draw ball
Post by: well20152016 on April 12, 2019, 12:21:07 PM
Are there any programs that can automatically generate sphere boxes?
Title: Re: Algorithm: Draw ball
Post by: ribarm on April 12, 2019, 01:05:51 PM
Look I've counted your last example - it seems 12 regular pentagons and 110 irregular hexagons... I'll attach my counted version - you can check if you want...
To answer your question : there are lisps for geodesic spheres and also there are lisps for all kind of dense covered spheres with regular triangles, quads, pentagons and hexagons based on uniform polyhedrons...
M.R.
Title: Re: Algorithm: Draw ball
Post by: ribarm on April 14, 2019, 04:38:12 AM
Here is my version of the same ball - 12 pentagons + 110 hexagons... I constructed based on dodecahedron - the problem still exist - we don't know ratio : edge of pentagon/hexagon : radius of sphere... I almost did it visually, but then the problem occurred when 2 cups had to be connected (bottom and top cup)... It seems that edge of pentagon should be little bigger, but we don't know how to determine that accurately...

Regards, M.R.

[EDIT : DWG removed due to lack of interest - not even single download up to now... See date of edit below post...]
Title: Re: Algorithm: Draw ball
Post by: ribarm on April 14, 2019, 10:07:13 AM
Here, I scaled pentagons with help of small routine, but the best I could get is 220 trapezoids instead of haxagons to finally make 3DSOLID... It looks very difficult to make it from real planar haxagons...

[EDIT : DWG removed due to lack of interest - not even single download up to now... See date of edit below post...]
Title: Re: Algorithm: Draw ball
Post by: ribarm on April 14, 2019, 11:43:20 AM
What I meant to say 12 regular pentagons, 20 irregular hexagons and 180 trapezoids...

(You are my density... What I meant to say, my destiny...)
Where did I hear this, I wonder...
M.R.
8-)
Title: Re: Algorithm: Draw ball
Post by: ribarm on April 16, 2019, 09:04:05 AM
For ruggby, american football... Just joking...
:2funny:
Title: Re: Algorithm: Draw ball
Post by: Mark on April 17, 2019, 07:54:32 AM
Very cool stuff. :)
Title: Re: Algorithm: Draw ball
Post by: ribarm on April 17, 2019, 07:59:28 AM
Very cool stuff. :)

I haven't checked video, but I made presentation of redesign of soccer ball...
https://youtu.be/a8uUK7-N1iU

Of course, thanks for pushing me to do it... @well20152016 was the one that deserves gratitude too...

M.R.
Title: Re: Algorithm: Draw ball
Post by: ribarm on April 19, 2019, 08:11:56 AM
Another video, now 3D MODEL of HOUSE based on SOCCER BALL design... Don't quite know for materials, but all faces are planar, so it could be from glass or something flat... It could be very simple, but could be also with larger scales...

https://youtu.be/lf0aIs_lnWo

M.R.
Title: Re: Algorithm: Draw ball
Post by: ribarm on April 21, 2019, 10:25:41 AM
This polyhedron has 12 pentagons and 50 quads+triangles... I don't know how Langner sphere is constructed with 12 pentagons and 60 hexagons - this must be some kind of magic I can't imagine...