Does any one have any code or know of any for a double helix object?

Thanks,
Rik Kline

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In article <3906DDC6.6A137E88@erols.com>, Rik Kline <rik### [at] erolscom> 
wrote:

> Does any one have any code or know of any for a double helix object?

Try something like this(untested!):
#macro DoubleHelix(Num, Twists, Height, Radius, MinorRadius, Offset)
    union {
        #local J=0;
        #while(J<Num)
            sphere {< Radius, Height*J/(Num-1), 0>, MinorRadius
                rotate y*360*Twists*J/(Num-1)
            }
            sphere {< Radius, Height*J/(Num-1), 0>, MinorRadius
                rotate y*360*Twists*J/(Num-1) + y*Offset
            }
            #local J=J+1;
        #end
    }
#end

-- 
Christopher James Huff - Personal e-mail: chr### [at] yahoocom
TAG(Technical Assistance Group) e-mail: chr### [at] tagpovrayorg
Personal Web page: http://chrishuff.dhs.org/
TAG Web page: http://tag.povray.org/

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Chris Huff <chr### [at] yahoocom> writes:

> In article <3906DDC6.6A137E88@erols.com>, Rik Kline <rik### [at] erolscom> 
> wrote:
> 
> > Does any one have any code or know of any for a double helix object?
> 
> Try something like this(untested!):
> #macro DoubleHelix(Num, Twists, Height, Radius, MinorRadius, Offset)
>     union {
>         #local J=0;
>         #while(J<Num)
>             sphere {< Radius, Height*J/(Num-1), 0>, MinorRadius
>                 rotate y*360*Twists*J/(Num-1)
>             }
>             sphere {< Radius, Height*J/(Num-1), 0>, MinorRadius
>                 rotate y*360*Twists*J/(Num-1) + y*Offset
>             }
>             #local J=J+1;
>         #end
>     }
> #end

Or use the helix object in the megapatch.

Thomas

-- 
http://thomas.willhalm.de/ (includes pgp key)

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Thanks

Chris Huff wrote:

> In article <3906DDC6.6A137E88@erols.com>, Rik Kline <rik### [at] erolscom>
> wrote:
>
> > Does any one have any code or know of any for a double helix object?
>
> Try something like this(untested!):
> #macro DoubleHelix(Num, Twists, Height, Radius, MinorRadius, Offset)
>     union {
>         #local J=0;
>         #while(J<Num)
>             sphere {< Radius, Height*J/(Num-1), 0>, MinorRadius
>                 rotate y*360*Twists*J/(Num-1)
>             }
>             sphere {< Radius, Height*J/(Num-1), 0>, MinorRadius
>                 rotate y*360*Twists*J/(Num-1) + y*Offset
>             }
>             #local J=J+1;
>         #end
>     }
> #end
>
> --
> Christopher James Huff - Personal e-mail: chr### [at] yahoocom
> TAG(Technical Assistance Group) e-mail: chr### [at] tagpovrayorg
> Personal Web page: http://chrishuff.dhs.org/
> TAG Web page: http://tag.povray.org/

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In article <qqm### [at] schlattfmiuni-konstanzde>, Thomas 
Willhalm <tho### [at] willhalmde> wrote:

> Or use the helix object in the megapatch.

There is no such thing as a helix object, not even in MegaPOV. You could 
do it with the parametric or the isosurface objects in MegaPOV, though.

-- 
Christopher James Huff - Personal e-mail: chr### [at] yahoocom
TAG(Technical Assistance Group) e-mail: chr### [at] tagpovrayorg
Personal Web page: http://chrishuff.dhs.org/
TAG Web page: http://tag.povray.org/

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On Wed, 26 Apr 2000 15:19:27 -0500, Chris Huff
<chr### [at] yahoocom> wrote:

>> Or use the helix object in the megapatch.
>
>There is no such thing as a helix object, not even in MegaPOV. You could 
>do it with the parametric or the isosurface objects in MegaPOV, though.

I think Thomas had in mind the built-in helix isosurface function.


Peter Popov ICQ : 15002700
Personal e-mail : pet### [at] usanet
TAG      e-mail : pet### [at] tagpovrayorg

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There is actually a 'Helix' object in the Includes\Shapesq.inc file.  Not sure if
that's
what was asked about or not though.  It's a twisted ribbon anyway.

Bob

"Chris Huff" <chr### [at] yahoocom> wrote in message
news:chrishuff_99-2B2E18.15192726042000@news.povray.org...
| In article <qqm### [at] schlattfmiuni-konstanzde>, Thomas
| Willhalm <tho### [at] willhalmde> wrote:
|
| > Or use the helix object in the megapatch.
|
| There is no such thing as a helix object, not even in MegaPOV. You could
| do it with the parametric or the isosurface objects in MegaPOV, though.

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Peter Popov <pet### [at] usanet> writes:

> On Wed, 26 Apr 2000 15:19:27 -0500, Chris Huff
> <chr### [at] yahoocom> wrote:
> 
> >> Or use the helix object in the megapatch.
> >
> >There is no such thing as a helix object, not even in MegaPOV. You could 
> >do it with the parametric or the isosurface objects in MegaPOV, though.
> 
> I think Thomas had in mind the built-in helix isosurface function.

You're right. I should have given a more detailed answer. Here is a small
scene that uses the helix isosurface function:

#version unofficial MegaPov 0.4;
camera { location <4,2,0> look_at <0,0,0> }
light_source { <10,10,10> color 1 }

#declare rad1 = 1;
#declare rad2 = 0.2FF;
#declare length = 0.5;
isosurface { 
  function "helix1", <2, 2*pi*length, rad2, rad1, 1, 1, 0> 
  contained_by{ 
    box <-rad1-rad2-0.001, -2,-rad1-rad2-0.001>, 
    <rad1+rad2+0.001, 2, rad1+rad2+0.001> 
  }
  pigment { color rgb 1 }
}

Thomas

-- 
http://thomas.willhalm.de/ (includes pgp key)

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Chris Huff wrote:

> Try something like this(untested!):
> #macro DoubleHelix(Num, Twists, Height, Radius, MinorRadius, Offset)
>     union {
>         #local J=0;
>         #while(J<Num)
>             sphere {< Radius, Height*J/(Num-1), 0>, MinorRadius
>                 rotate y*360*Twists*J/(Num-1)
>             }
>             sphere {< Radius, Height*J/(Num-1), 0>, MinorRadius
>                 rotate y*360*Twists*J/(Num-1) + y*Offset
>             }
>             #local J=J+1;
>         #end
>     }
> #end

I would use a low-throshold blob; less damanding on resources and faster to
render.

--
David Fontaine     <dav### [at] faricynet>    ICQ 55354965
Please visit my website: http:/www.faricy.net/~davidf/

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