POV-Ray : Newsgroups : povray.programming : Algorythm for BLOB to mesh Server Time
26 Dec 2024 10:20:09 EST (-0500)
  Algorythm for BLOB to mesh (Message 1 to 10 of 10)  
From: Skelter
Subject: Algorythm for BLOB to mesh
Date: 6 Jul 1999 17:50:45
Message: <37827a35@news.povray.org>
Can anyone direct me towards an algorythm for calculating a mesh from a
blob?

-s


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From: Anders Haglund
Subject: Re: Algorythm for BLOB to mesh
Date: 6 Jul 1999 21:47:41
Message: <3782b1bd@news.povray.org>
Skelter <ske### [at] nospamfull-mooncom> wrote in message
news:37827a35@news.povray.org...
> Can anyone direct me towards an algorythm for calculating a mesh from a
> blob?
In povray? Impossible.
In general? Use marching cubes.

I can direct you to a nice site about marching cubes if you want to. You
won't need it
if your not a programmer anyway and I'm too tired to find it now...
/Anders


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From: Skelter
Subject: Re: Algorythm for BLOB to mesh
Date: 22 Jul 1999 13:07:27
Message: <37974fcf@news.povray.org>
I am a programmer.  Marching cubes.  That should get me started.


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From: Anders Haglund
Subject: Re: Algorythm for BLOB to mesh
Date: 22 Jul 1999 14:29:54
Message: <37976322@news.povray.org>
Skelter <ske### [at] nospamfull-mooncom> wrote in message
news:37974fcf@news.povray.org...
> I am a programmer.  Marching cubes.  That should get me started.

check out http://www.mhri.edu.au/~pdb/modelling/polygonise/
gr8 page 'bout marching cubes.

/Anders


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From: Mike
Subject: Re: Algorythm for BLOB to mesh
Date: 22 Jul 1999 19:20:08
Message: <3797A55E.CC52A8A@aol.com>
Look for papers on marching triangles as well.  I hear it's faster and
more accurate than marching cubes.

-Mike

Skelter wrote:

> I am a programmer.  Marching cubes.  That should get me started.


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From: Mark Wagner
Subject: Re: Algorythm for BLOB to mesh
Date: 23 Jul 1999 00:50:41
Message: <3797f4a1@news.povray.org>
Mike wrote in message <379### [at] aolcom>...
>Look for papers on marching triangles as well.  I hear it's faster and
>more accurate than marching cubes.
>
And, as mentioned in the isosurface-to-mesh thread, it isn't patented.


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From: Anders Haglund
Subject: Re: Algorythm for BLOB to mesh
Date: 23 Jul 1999 00:51:19
Message: <3797f4c7@news.povray.org>
Mike <Ama### [at] aolcom> wrote in message news:379### [at] aolcom...
> Look for papers on marching triangles as well.  I hear it's faster and
> more accurate than marching cubes.
>
> -Mike

You can find almost anything on Paul Bourke's pages :)
here is his page about "marching triangles", as you call it:
http://www.mhri.edu.au/~pdb/modelling/polytetra/

/Anders


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From: Jerry Anning
Subject: Re: Algorythm for BLOB to mesh
Date: 23 Jul 1999 12:09:54
Message: <379891e8.3149530@news.povray.org>
On Fri, 23 Jul 1999 06:51:53 +0200, "Anders Haglund"
<and### [at] hotmailcom> wrote:

>
>Mike <Ama### [at] aolcom> wrote in message news:379### [at] aolcom...
>> Look for papers on marching triangles as well.  I hear it's faster and
>> more accurate than marching cubes.
>>
>> -Mike
>
>You can find almost anything on Paul Bourke's pages :)
>here is his page about "marching triangles", as you call it:
>http://www.mhri.edu.au/~pdb/modelling/polytetra/
>
>/Anders
>
>
The algorithm Bourke describes on this page is simply a tetrahedral
variant on Marching Cubes.  Marching Triangles is a very different
thing.  In particular, it is surface based, involves evaluating
Delaunay triangulation surface constraints, and doesn't constrain
vertices to a regular mesh.  For Marching Triangles info from the
source, go to http://www.ee.surrey.ac.uk/Research/VSSP/3DVision.html.

Jerry Anning
clem "at" dhol "dot" com


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From: Ken
Subject: Re: Algorythm for BLOB to mesh
Date: 23 Jul 1999 12:21:42
Message: <37989610.887930E9@pacbell.net>
That link should be:

http://www.ee.surrey.ac.uk/Research/VSSP/3DVision/mt.html

-- 
Ken Tyler
  
mailto://tylereng@pacbell.net
http://home.pacbell.net/tylereng/links.htm


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From: David Newman
Subject: Re: Algorythm for BLOB to mesh
Date: 29 Jul 1999 15:03:45
Message: <37A0A7B3.743BF8FE@dial.pipex.com>
Well, aside from marching cubes, how about this for an algorithm - the
whole idea of polygonising a surface anyway is to fool the eye into
thinking it's smooth whilst speeding rendering speed. So why not set a
certain threshold of the exterior angles, ie. For slight curves, use few
triangles/polygons/whatever, for steep curves, use loadsa
triangles/you-name it..... This means less memory is used.

Anyway, just an idea....... any thoughts / suggestions on how to
implement??????



Skelter wrote:

> Can anyone direct me towards an algorythm for calculating a mesh from a
> blob?
>
> -s


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