I've seen metal plates and surfaces that are covered with polished circles,
which I assume is due to being formed by a vertical milling machine.

Any idea how I can do that with a texture in POV?

--John

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John M. Dlugosz wrote:
> 
> I've seen metal plates and surfaces that are covered with polished circles,
> which I assume is due to being formed by a vertical milling machine.
> 
> Any idea how I can do that with a texture in POV?

If I understand what you're referring to, I'm thinking that your best
chance at doing this is creating an image (with lots of little circles)
and using it as a normal, then playing with specular to bring out the
high points. To make it look real, though, you'd need to render the
scene at some huge resolution, in order to match the resolving power of
the human eye and preserve the fine detail that the effect calls for.
Otherwise you'd end up with something that was either (a) crude and
unrealistic or (b) just shiny.

-Xplo

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Xplo Eristotle <inq### [at] unforgettablecom> wrote:
: If I understand what you're referring to, I'm thinking that your best
: chance at doing this is creating an image (with lots of little circles)

  Why?
  Circles can be easyly done with procedural textures.

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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Nieminen Juha <war### [at] cctutfi> wrote in message
news:37cd3960@news.povray.org...
> Xplo Eristotle <inq### [at] unforgettablecom> wrote:
> : If I understand what you're referring to, I'm thinking that your best
> : chance at doing this is creating an image (with lots of little circles)
>
>   Why?
>   Circles can be easyly done with procedural textures.
>

Which is exactly what I'm asking... care to demonstrate?  Ripples or Waves
can produce one milling circle pattern, but the surface is covered with them
in a grid pattern so the edges just overlap a little, like scallop shells.

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"John M. Dlugosz" wrote:
> 
> Nieminen Juha <war### [at] cctutfi> wrote in message
> news:37cd3960@news.povray.org...
> > Xplo Eristotle <inq### [at] unforgettablecom> wrote:
> > : If I understand what you're referring to, I'm thinking that your best
> > : chance at doing this is creating an image (with lots of little circles)
> >
> >   Why?
> >   Circles can be easyly done with procedural textures.
> >
> 
> Which is exactly what I'm asking... care to demonstrate?  Ripples or Waves
> can produce one milling circle pattern, but the surface is covered with them
> in a grid pattern so the edges just overlap a little, like scallop shells.

Try a repeat warp on the pattern.

-- 
Ken Tyler

See my 850+ Povray and 3D Rendering and Raytracing Links at:
http://home.pacbell.net/tylereng/index.html

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On Wed, 01 Sep 1999 18:14:03 -0700, Ken <tyl### [at] pacbellnet> wrote:

>
>
>"John M. Dlugosz" wrote:
>> 
>> Nieminen Juha <war### [at] cctutfi> wrote in message
>> news:37cd3960@news.povray.org...
>> > Xplo Eristotle <inq### [at] unforgettablecom> wrote:
>> > : If I understand what you're referring to, I'm thinking that your best
>> > : chance at doing this is creating an image (with lots of little circles)
>> >
>> >   Why?
>> >   Circles can be easyly done with procedural textures.
>> >
>> 
>> Which is exactly what I'm asking... care to demonstrate?  Ripples or Waves
>> can produce one milling circle pattern, but the surface is covered with them
>> in a grid pattern so the edges just overlap a little, like scallop shells.
>
>Try a repeat warp on the pattern.

won't work.  The pattern he's talking about has roughly circular
boundaries, and a repeat warp will put noticeable straight lines
in the pattern.

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John M. Dlugosz <joh### [at] dlugoszcom> wrote:
: Which is exactly what I'm asking... care to demonstrate?  Ripples or Waves
: can produce one milling circle pattern, but the surface is covered with them
: in a grid pattern so the edges just overlap a little, like scallop shells.

  I'm not sure if I understand at all what do you mean.
  Do you mean something like this?

camera { location <0,10,-10> look_at 0 angle 35 }
light_source { <100,100,-100> 1 }
plane
{ y,0
  pigment { rgb x }
  finish { specular .5 }
  normal
  { wood 1 slope_map
    { [0 <0,2>]
      [.5 <1,0>]
      [1 <0,-2>]
    }
    rotate x*90
  }
}

  Modify the slope map at will.

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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Ron Parker wrote:

> >Try a repeat warp on the pattern.
> 
> won't work.  The pattern he's talking about has roughly circular
> boundaries, and a repeat warp will put noticeable straight lines
> in the pattern.

I think I will stop posting suggestions for the rest of the week. Suggestion
burn out I suppose. Did anyone else just hear that crackling sound in my head ?

-- 
Ken Tyler

See my 850+ Povray and 3D Rendering and Raytracing Links at:
http://home.pacbell.net/tylereng/index.html

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On Tue, 31 Aug 1999 22:10:29 -0500, "John M. Dlugosz"
<joh### [at] dlugoszcom> wrote:

>I've seen metal plates and surfaces that are covered with polished circles,
>which I assume is due to being formed by a vertical milling machine.
>
>Any idea how I can do that with a texture in POV?
>
>--John
>

1. (easiest) Use a ripples normal along with Chris Colefax's texture
tiler macro 

2. (harder) Use an average of 10-20 randomly displaced (in the plane)
normals using the spherical pattern with a high frequency and a repeat
warp set up so that it does not intersect the pattern edges

3. (easy, Superpatch reuqired) Use an isosurface normal

4. (has its drawbacks) Rob a bank (you only need $3600) and then ask
Lance what to do :) "MAX.....3.0.... mumble.....mumble... yeah
kewl..... mumble ......anisotropic....mumble..... shading.....
nah...it's... cheap.....mumble....." etc, mumble <grin>


Peter Popov
ICQ: 15002700

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This could be done quite well with the crackle normal with a high frequency.
However, the crackle pattern in official POV will always give angular, rather
than circular features. I think the modified crackle pattern in the Superpatch
could produce almost exactly what you are looking for - if you're willing to
give it a try.
And whatever method you use, expect aliasing galore! My current background image
also imitates the milled metal effect. While I actually wanted the interference
patterns, it is probably not desirable in your case. Plus the render time was
HUGE.

Margus

"John M. Dlugosz" wrote:
> 
> I've seen metal plates and surfaces that are covered with polished circles,
> which I assume is due to being formed by a vertical milling machine.
> 
> Any idea how I can do that with a texture in POV?
> 
> --John

Post a reply to this message