I had an idea for a hair generator a couple of days ago. It's probably been
done
before, but I had fun trying it out. The hair generator is given a vector
and an angle
and the hairs bend towards that vector by the specified angle

First pic is a simple blob, second shows the hair on a julia fractal.
Third pic shows the hair on the poser cat. For better realism, the cat could
be split into sections (head, body, legs, tail) and the hair applied to each
individually.

All render times are under 5 min.

Comments?

Gail
--
#macro G(H,S)disc{0z.4pigment{onion color_map{[0rgb<sin(H/pi)cos(S/pi)*(H<6)
cos(S/pi)*(H>6)>*18][.4rgb 0]}}translate<H-5S-3,9>}#end G(3,5)G(2,5.5)G(1,5)
G(.6,4)G(.5,3)G(.6,2)G(1,1)G(2,.5)G(3,.7)G(3.2,1.6)G(3.1,2.5)G(2.2,2.5)G(9,5
)G(8,5.5)G(7,5)G(7,4)G(7.7,3.3)G(8.3,2.7)G(9,2)G(9,1)G(8,.5)G(7,1)///GS

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Attachments:
Download 'HairBlob.jpg' (58 KB) Download 'HairFractal.jpg' (25 KB) Download 'HairCat.jpg' (24 KB)

Preview of image 'HairBlob.jpg'

Preview of image 'HairFractal.jpg'

Preview of image 'HairCat.jpg'

It looks promising.

I tried the same some time ago but I gave up because
rendering time was too high when the number of hairs
reached more or less real numbers.

I also used eval_pigment function to assign different
colors.

Maybe there is no need (if you don't use reflections) to
create hair on the invisible side of the object. But that
will make the logic even more complicated ;)

Gena.

Gail Shaw wrote:

> I had an idea for a hair generator a couple of days ago. It's probably been
> done
> before, but I had fun trying it out. The hair generator is given a vector
> and an angle
> and the hairs bend towards that vector by the specified angle
>
> First pic is a simple blob, second shows the hair on a julia fractal.
> Third pic shows the hair on the poser cat. For better realism, the cat could
> be split into sections (head, body, legs, tail) and the hair applied to each
> individually.
>
> All render times are under 5 min.
>
> Comments?
>
> Gail
> --
> #macro G(H,S)disc{0z.4pigment{onion color_map{[0rgb<sin(H/pi)cos(S/pi)*(H<6)
> cos(S/pi)*(H>6)>*18][.4rgb 0]}}translate<H-5S-3,9>}#end G(3,5)G(2,5.5)G(1,5)
> G(.6,4)G(.5,3)G(.6,2)G(1,1)G(2,.5)G(3,.7)G(3.2,1.6)G(3.1,2.5)G(2.2,2.5)G(9,5
> )G(8,5.5)G(7,5)G(7,4)G(7.7,3.3)G(8.3,2.7)G(9,2)G(9,1)G(8,.5)G(7,1)///GS
>
>  [Image]
>
>  [Image]
>
>  [Image]

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While working on POV-Ray "filters" I found another
idea for hair - to use cylinder blobs which are perpendicular
to the surface normal. In this case you will get more smooth
surface with just relief of hair instead of separate hair.

Gena.

Gail Shaw wrote:

> I had an idea for a hair generator a couple of days ago. It's probably been
> done
> before, but I had fun trying it out. The hair generator is given a vector
> and an angle
> and the hairs bend towards that vector by the specified angle
>
> First pic is a simple blob, second shows the hair on a julia fractal.
> Third pic shows the hair on the poser cat. For better realism, the cat could
> be split into sections (head, body, legs, tail) and the hair applied to each
> individually.
>
> All render times are under 5 min.
>
> Comments?
>
> Gail
> --
> #macro G(H,S)disc{0z.4pigment{onion color_map{[0rgb<sin(H/pi)cos(S/pi)*(H<6)
> cos(S/pi)*(H>6)>*18][.4rgb 0]}}translate<H-5S-3,9>}#end G(3,5)G(2,5.5)G(1,5)
> G(.6,4)G(.5,3)G(.6,2)G(1,1)G(2,.5)G(3,.7)G(3.2,1.6)G(3.1,2.5)G(2.2,2.5)G(9,5
> )G(8,5.5)G(7,5)G(7,4)G(7.7,3.3)G(8.3,2.7)G(9,2)G(9,1)G(8,.5)G(7,1)///GS
>
>  [Image]
>
>  [Image]
>
>  [Image]

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"Gail Shaw" <gai### [at] mwebcoza> wrote in
news:3dac694b@news.povray.org: 

> Comments?

Interesting!


-- 
(MIKA) Marc Champagne
marcch.AT.videotron.DOT.ca
Montreal, CANADA

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Fascinating, and I am glad that is not my cat.

Cheers!

Chip Shults
My robotics, space and CGI web page - http://home.cfl.rr.com/aichip

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Very interesting!  Most hair generators require mesh!

 
> 
>

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Hairy Fractals Batman!

--
Rick

Kitty5 NewMedia http://Kitty5.co.uk
POV-Ray News & Resources http://Povray.co.uk
TEL : +44 (01270) 501101 - FAX : +44 (01270) 251105 - ICQ : 15776037

PGP Public Key
http://pgpkeys.mit.edu:11371/pks/lookup?op=get&search=0x231E1CEA



---

Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.401 / Virus Database: 226 - Release Date: 09/10/2002

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Very nice work! The blob looks good, the fractal looks strangely disturbing
(like some kinda alien sea creature - maybe a shellfish), and the cat
looks... well... odd.

I wonder what else you could fir up? ;-)
Andrew.

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Unusual. Poor kitty cat needs a vet's attention though  :-)

That fractal is neat, makes me think of microbes or other strange creatures.
I didn't realize it at first but the directional hairs of the blob make me
think of wind. Wonder if it could be animated to look like air were blowing
across it. Would need a certain order of placement for that I guess, each
angle adjusted as the hair objects are placed along an axis.

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Marc Champagne <nos### [at] pleasecom> wrote in news:Xns92A8C5CFD6979POVMIKA@
204.213.191.226:

> "Gail Shaw" <gai### [at] mwebcoza> wrote in
> news:3dac694b@news.povray.org: 
> 
>> Comments?
> 
> Interesting!
> 
> 

Heu, Andrew, is that you?


-- 
-+======================+-
 Martin Bélair [MAB]
 Montréal, Québec, Canada
 bad### [at] hotmailDOTcom
-+======================+-

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Martin Belair <bad### [at] hotmailDOTcom> wrote in
news:Xns### [at] 204213191226: 

> Marc Champagne <nos### [at] pleasecom> wrote in
> news:Xns92A8C5CFD6979POVMIKA@ 204.213.191.226:
>
>> Interesting!
> 
> Heu, Andrew, is that you?

Cool! I like that very much!

-- 
(MIKA) Marc Champagne
marcch.AT.videotron.DOT.ca
Montreal, CANADA

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Gail Shaw wrote:

> I had an idea for a hair generator a couple of days ago. It's probably
> been done before, but I had fun trying it out.

Interesting images. How did you distribute the hairs and determine the
normal of the surface? With the trace function?

Thomas

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"Sir Charles W. Shults III" <aic### [at] cflrrcom> wrote in message
news:3daccdff$3@news.povray.org...
>     Fascinating,

Thanks

> and I am glad that is not my cat

Likewise

Gail
--
#macro G(H,S)disc{0z.4pigment{onion color_map{[0rgb<sin(H/pi)cos(S/pi)*(H<6)
cos(S/pi)*(H>6)>*18][.4rgb 0]}}translate<H-5S-3,9>}#end G(3,5)G(2,5.5)G(1,5)
G(.6,4)G(.5,3)G(.6,2)G(1,1)G(2,.5)G(3,.7)G(3.2,1.6)G(3.1,2.5)G(2.2,2.5)G(9,5
)G(8,5.5)G(7,5)G(7,4)G(7.7,3.3)G(8.3,2.7)G(9,2)G(9,1)G(8,.5)G(7,1)///GS

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"Rick [Kitty5]" <ric### [at] kitty5com> wrote in message
news:3dad2f41@news.povray.org...
> Hairy Fractals Batman!
>

LOL

Gail
--
#macro G(H,S)disc{0z.4pigment{onion color_map{[0rgb<sin(H/pi)cos(S/pi)*(H<6)
cos(S/pi)*(H>6)>*18][.4rgb 0]}}translate<H-5S-3,9>}#end G(3,5)G(2,5.5)G(1,5)
G(.6,4)G(.5,3)G(.6,2)G(1,1)G(2,.5)G(3,.7)G(3.2,1.6)G(3.1,2.5)G(2.2,2.5)G(9,5
)G(8,5.5)G(7,5)G(7,4)G(7.7,3.3)G(8.3,2.7)G(9,2)G(9,1)G(8,.5)G(7,1)///GS

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"Andrew Coppin" <orp### [at] btinternetcom> wrote in message
news:3dad5319@news.povray.org...
> Very nice work! The blob looks good, the fractal looks strangely
disturbing
> (like some kinda alien sea creature - maybe a shellfish),

Thanks

> and the cat
> looks... well... odd.

It's actually not too bad from a distance

> I wonder what else you could fir up? ;-)

Hmmmm...........

Gail
--
#macro G(H,S)disc{0z.4pigment{onion color_map{[0rgb<sin(H/pi)cos(S/pi)*(H<6)
cos(S/pi)*(H>6)>*18][.4rgb 0]}}translate<H-5S-3,9>}#end G(3,5)G(2,5.5)G(1,5)
G(.6,4)G(.5,3)G(.6,2)G(1,1)G(2,.5)G(3,.7)G(3.2,1.6)G(3.1,2.5)G(2.2,2.5)G(9,5
)G(8,5.5)G(7,5)G(7,4)G(7.7,3.3)G(8.3,2.7)G(9,2)G(9,1)G(8,.5)G(7,1)///GS

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"hughes, b." <omn### [at] charternet> wrote in message
news:3dad5568@news.povray.org...
> Unusual. Poor kitty cat needs a vet's attention though  :-)

LOL

> That fractal is neat, makes me think of microbes or other strange
creatures.
> I didn't realize it at first but the directional hairs of the blob make me
> think of wind. Wonder if it could be animated to look like air were
blowing
> across it. Would need a certain order of placement for that I guess, each
> angle adjusted as the hair objects are placed along an axis.

Probably could, not very realistically in the current version but it
shouldn't be too hard

Gail
--
#macro G(H,S)disc{0z.4pigment{onion color_map{[0rgb<sin(H/pi)cos(S/pi)*(H<6)
cos(S/pi)*(H>6)>*18][.4rgb 0]}}translate<H-5S-3,9>}#end G(3,5)G(2,5.5)G(1,5)
G(.6,4)G(.5,3)G(.6,2)G(1,1)G(2,.5)G(3,.7)G(3.2,1.6)G(3.1,2.5)G(2.2,2.5)G(9,5
)G(8,5.5)G(7,5)G(7,4)G(7.7,3.3)G(8.3,2.7)G(9,2)G(9,1)G(8,.5)G(7,1)///GS

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"Thomas Willhalm" <tho### [at] uni-konstanzde> wrote in message
news:3dae744f@news.povray.org...
>
> Interesting images. How did you distribute the hairs and determine the
> normal of the surface? With the trace function?

The macro takes a outer radius and an inner radius as parameters. A random
point is chosen on each. trace is used from the chosen point on the outer
sphere to
the chosen point on the inner sphere to determine the intersection point and
normal.

Gail
--
#macro G(H,S)disc{0z.4pigment{onion color_map{[0rgb<sin(H/pi)cos(S/pi)*(H<6)
cos(S/pi)*(H>6)>*18][.4rgb 0]}}translate<H-5S-3,9>}#end G(3,5)G(2,5.5)G(1,5)
G(.6,4)G(.5,3)G(.6,2)G(1,1)G(2,.5)G(3,.7)G(3.2,1.6)G(3.1,2.5)G(2.2,2.5)G(9,5
)G(8,5.5)G(7,5)G(7,4)G(7.7,3.3)G(8.3,2.7)G(9,2)G(9,1)G(8,.5)G(7,1)///GS

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