description, another views :
http://www.raf256.com/pov/chrome

generaly - image represents blured reflection made by very small normal and 
big anit alias

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Attachments:
Download '055.png' (328 KB)

Preview of image '055.png'

"Rafal 'Raf256' Maj" <raf### [at] raf256com> schrieb im Newsbeitrag
news:Xns### [at] 204213191226...
>
> description, another views :
> http://www.raf256.com/pov/chrome
>
> generaly - image represents blured reflection made by very small normal
and
> big anit alias
>

Well ... that was a big file for such a generic picture. As you even gave a
URL, you could have made some nice small Jpeg.

Marc-Hendrik

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Rafal 'Raf256' Maj wrote:
> 
> description, another views :
> http://www.raf256.com/pov/chrome
> 
> generaly - image represents blured reflection made by very small normal and
> big anit alias
> 
> begin 644 055.png
> [...]

I wonder when you will manage to configure your newsreader to generate
readable attachments.  

Some technical comments:

- a 15x15 area_light does not have much effect in such a scene apart from
making it slow.

- the finish could use metallic reflection.

- what's described in
http://www.students.tut.fi/~warp/povQandT/languageQandT.html#blurredreflection
is probably a better way for achieving realistic reflection blur.

- using 'recursion_limit 3' for radiosity would be similarly useless as
the 15x15 area_light.


Christoph

-- 
POV-Ray tutorials, IsoWood include,                 
TransSkin and more: http://www.tu-bs.de/~y0013390/  
Last updated 13 Aug. 2002 _____./\/^>_*_<^\/\.______

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Christoph Hormann <chr### [at] gmxde> wrote in
news:3D60B33C.21A3FECA@gmx.de 

> I wonder when you will manage to configure your newsreader to generate
> readable attachments.

I do what I can... many peoples see attachment
 
> - a 15x15 area_light does not have much effect in such a scene apart
> from making it slow.

at i.e 10x10 the difference was notacible
 
> - the finish could use metallic reflection.

it use it, as described on www
 
> - what's described in
> http://www.students.tut.fi/~warp/povQandT/languageQandT.html#blurredref
> lection is probably a better way for achieving realistic reflection
> blur. 

looks interesting :_ I'll play with it



-- 
#macro g(U,V)(.4*abs(sin(9*sqrt(pow(x-U,2)+pow(y-V,2))))*pow(1-min(1,(sqrt(
pow(x-U,2)+pow(y-V,2))*.3)),2)+.9)#end#macro p(c)#if(c>1)#local l=mod(c,100
);g(2*div(l,10)-8,2*mod(l,10)-8)*p(div(c,100))#else 1#end#end light_source{
y 2}sphere{z*20 9pigment{function{p(26252423)*p(36455644)*p(66656463)}}}//M

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Rafal 'Raf256' Maj wrote:
> 
> [...]
> 
> > - the finish could use metallic reflection.
> 
> it use it, as described on www
> 

No, that's just for metallic specular highlights.


Christoph

-- 
POV-Ray tutorials, IsoWood include,                 
TransSkin and more: http://www.tu-bs.de/~y0013390/  
Last updated 13 Aug. 2002 _____./\/^>_*_<^\/\.______

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Christoph Hormann wrote:
> - what's described in
> 
http://www.students.tut.fi/~warp/povQandT/languageQandT.html#blurredreflection
> is probably a better way for achieving realistic reflection blur.

  Hmmmm... I'm not that sure. You mean perhaps that it is much more easy to 
setup and (somewhat) faster. But I tried both methods and can't still 
decide wich one produces "more realistic" results. 

  Rafal aproach is not that bad, but I found that it works better with 
focal_blur than with aa. I also prefer the cells patern for this technique, 
as it seems to give the most smooth results.  Here is a sample with 192 
blur_samples (damn slow):

    http://www.ignorancia.org/images/microcells08-192bs.jpg

  and the same scene without "micro-normals":

    http://www.ignorancia.org/images/micro-no_brush.jpg


 -- 
Jaime Vives Piqueres

La Persistencia de la Ignorancia
http://www.ignorancia.org

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Jaime Vives Piqueres wrote:
> 
> http://www.students.tut.fi/~warp/povQandT/languageQandT.html#blurredreflection
> > is probably a better way for achieving realistic reflection blur.
> 
>   Hmmmm... I'm not that sure. You mean perhaps that it is much more easy to
> setup and (somewhat) faster. But I tried both methods and can't still
> decide wich one produces "more realistic" results.

I was mostly referring to speed, apart from that it's never good if a
technique totally depends on aa (or focal_blur) to function.

>   Rafal aproach is not that bad, but I found that it works better with
> focal_blur than with aa. I also prefer the cells patern for this technique,
> as it seems to give the most smooth results.  Here is a sample with 192
> blur_samples (damn slow):

Using focal blur for smoothing will not work in the focal plane, you will
always get a grainy appearance there.

BTW, did you use the default normal accuracy or a different value?

Christoph

-- 
POV-Ray tutorials, IsoWood include,                 
TransSkin and more: http://www.tu-bs.de/~y0013390/  
Last updated 13 Aug. 2002 _____./\/^>_*_<^\/\.______

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Christoph Hormann <chr### [at] gmxde> wrote in 
news:3D60D33D.D2E05C57@gmx.de

> I was mostly referring to speed, apart from that it's never good if a
> technique totally depends on aa (or focal_blur) to function.

yes, but this approach is realistic - if You zoom in real chrome object You 
will see that in fact it is quite sharp (as in zoom in on www).
And my normal works exacly that way.
I alsow foght about strong AA needed, and imho best solution is to use 
quality optin like

#declare QQ_DetailedNormal = 1;

and when option is "0" - use some i.e. bozo and ignore normals smalle rthen 
i.e. 0.1 (on 50.0 radius sphere)

-- 
#macro g(U,V)(.4*abs(sin(9*sqrt(pow(x-U,2)+pow(y-V,2))))*pow(1-min(1,(sqrt(
pow(x-U,2)+pow(y-V,2))*.3)),2)+.9)#end#macro p(c)#if(c>1)#local l=mod(c,100
);g(2*div(l,10)-8,2*mod(l,10)-8)*p(div(c,100))#else 1#end#end light_source{
y 2}sphere{z*20 9pigment{function{p(26252423)*p(36455644)*p(66656463)}}}//M

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Rafal 'Raf256' Maj wrote:
> 
> yes, but this approach is realistic - if You zoom in real chrome object You
> will see that in fact it is quite sharp (as in zoom in on www).
> And my normal works exacly that way.

I'm not sure what you think is realistic when rendering this technique in
a larger view, but the irregularities on a slightly dull metal surface are
always in microscopic scale (usually a few micrometer) so you won't see
them directly even if you 'zoom in'.  There is no point in trying to
create a physically correct model of the irregularities because you won't
be able to simulate the optical effects involved accurately.

> I alsow foght about strong AA needed, and imho best solution is to use
> quality optin like

Would you mind taking a bit more care about typing?  I would not complain
if this was about language style but it seems just mixing up characters. 
If the reason is some medical handicap i will understand of course.

Christoph

-- 
POV-Ray tutorials, IsoWood include,                 
TransSkin and more: http://www.tu-bs.de/~y0013390/  
Last updated 13 Aug. 2002 _____./\/^>_*_<^\/\.______

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Christoph Hormann <chr### [at] gmxde> wrote in
news:3D612786.5D37542C@gmx.de 

>> yes, but this approach is realistic - if You zoom in real chrome
>> object You will see that in fact it is quite sharp (as in zoom in on
>> www). And my normal works exacly that way.
> I'm not sure what you think is realistic when rendering this technique
> in a larger view, but the irregularities on a slightly dull metal
> surface are always in microscopic scale (usually a few micrometer) so
> you won't see them directly even if you 'zoom in'.  There is no point

ok. So this image is better to ilustrate tome type of not-polished, or 
rusty chrome. 
About blurred reflection - why this interesting future was not used in Pov 
3.5 ? I meen - where there some problems, or just authors deside this is 
not an important future ?

[FUT .general]

-- 
#macro g(U,V)(.4*abs(sin(9*sqrt(pow(x-U,2)+pow(y-V,2))))*pow(1-min(1,(sqrt(
pow(x-U,2)+pow(y-V,2))*.3)),2)+.9)#end#macro p(c)#if(c>1)#local l=mod(c,100
);g(2*div(l,10)-8,2*mod(l,10)-8)*p(div(c,100))#else 1#end#end light_source{
y 2}sphere{z*20 9pigment{function{p(26252423)*p(36455644)*p(66656463)}}}//M

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