Generate a solid cad model from available math functions

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Generate a solid cad model from available math functions

Katt
Hi all;

I have two math functions from which I am interested to generate a CAD
model.

Attached is a picture for what I am looking for but not sure how to do it.
<http://forum.openscad.org/file/t2047/cad_model.png>

The border line equations are given and the shaded black region is the one i
want to generate. Also note that the third dimension does not matter for me
as I am looking at a 2D case. It can be any flexible value.

Thanks!!

 



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Re: Generate a solid cad model from available math functions

Ronaldo
You need to define a polygon by its vertices. Something like:

verts = [for(i=[0:nverts-1]) [ i/verts, f(i/nverts) ] ];
polygon(verts);

This would be the upper part.

2018-01-10 13:32 GMT-02:00 Katt <[hidden email]>:
Hi all;

I have two math functions from which I am interested to generate a CAD
model.

Attached is a picture for what I am looking for but not sure how to do it.
<http://forum.openscad.org/file/t2047/cad_model.png>

The border line equations are given and the shaded black region is the one i
want to generate. Also note that the third dimension does not matter for me
as I am looking at a 2D case. It can be any flexible value.

Thanks!!





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Re: Generate a solid cad model from available math functions

Ronaldo
There was a typo in my previous code.

To get a symetrical shape, given the function f defined in the interval [0,1]:

    nverts = 10;
    scalex = 8;
    verts = concat(
                    [for(i=[0:nverts-1])    [ scalex*i/nverts,  f(i/nverts) ] ],
                    [for(i=[nverts-1:-1:0]) [ scalex*i/nverts, -f(i/nverts) ] ]
                  );
    polygon(verts);

2018-01-10 13:45 GMT-02:00 Ronaldo Persiano <[hidden email]>:
You need to define a polygon by its vertices. Something like:

verts = [for(i=[0:nverts-1]) [ i/verts, f(i/nverts) ] ];
polygon(verts);

This would be the upper part.

2018-01-10 13:32 GMT-02:00 Katt <[hidden email]>:
Hi all;

I have two math functions from which I am interested to generate a CAD
model.

Attached is a picture for what I am looking for but not sure how to do it.
<http://forum.openscad.org/file/t2047/cad_model.png>

The border line equations are given and the shaded black region is the one i
want to generate. Also note that the third dimension does not matter for me
as I am looking at a 2D case. It can be any flexible value.

Thanks!!





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tp3
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Re: Generate a solid cad model from available math functions

tp3
Just for completeness, in the dev snapshot version concat() is
not needed for this case anymore.

It's enough to simply write:

verts = [
  for(i=[0:nverts-1])    [ scalex*i/nverts,  f(i/nverts) ],
  for(i=[nverts-1:-1:0]) [ scalex*i/nverts, -f(i/nverts) ]
];

ciao,
  Torsten.

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Re: Generate a solid cad model from available math functions

cbernhardt
Here is some code with a function added for the y coord.
<http://forum.openscad.org/file/t1309/poly.jpg>




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