I have a very thin object that is not showing up correctly because some
pixels pick it up and others don't hence creating jaggies, even with
anti-aliasing. My question is, what do I adjust in anti-aliasing to improve
this? And does increasing or decreasing the threshold provide for a better
sample?

Thanks in advance!

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Chris Becker <cmb### [at] ritedu> wrote:
> I have a very thin object that is not showing up correctly because some
> pixels pick it up and others don't hence creating jaggies, even with
> anti-aliasing. My question is, what do I adjust in anti-aliasing to improve
> this? And does increasing or decreasing the threshold provide for a better
> sample?

  Try +a0.0 if it helps. (Note that it will slow down the rendering a lot.)

-- 
#macro N(D)#if(D>99)cylinder{M()#local D=div(D,104);M().5,2pigment{rgb M()}}
N(D)#end#end#macro M()<mod(D,13)-6mod(div(D,13)8)-3,10>#end blob{
N(11117333955)N(4254934330)N(3900569407)N(7382340)N(3358)N(970)}//  - Warp -

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I don't think this would be of much help here.
Try increasing the recursion depth (+r4 or +r5) instead, this also slow down things,
especially with method 2.

If this doesn't work either, render at bigger resolution and re-size your picture
with your favourite paint program.

--
Jonathan.

Home: http://digilander.iol.it/jrgpov


"Warp" <war### [at] tagpovrayorg> ha scritto nel messaggio
news:3ca678ed@news.povray.org...
> Chris Becker <cmb### [at] ritedu> wrote:
> > I have a very thin object that is not showing up correctly because some
> > pixels pick it up and others don't hence creating jaggies, even with
> > anti-aliasing. My question is, what do I adjust in anti-aliasing to improve
> > this? And does increasing or decreasing the threshold provide for a better
> > sample?
>
>   Try +a0.0 if it helps. (Note that it will slow down the rendering a lot.)
>
> --
> #macro N(D)#if(D>99)cylinder{M()#local D=div(D,104);M().5,2pigment{rgb M()}}
> N(D)#end#end#macro M()<mod(D,13)-6mod(div(D,13)8)-3,10>#end blob{
> N(11117333955)N(4254934330)N(3900569407)N(7382340)N(3358)N(970)}//  - Warp -

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JRG <jrg### [at] hotmailcom> wrote:
> If this doesn't work either, render at bigger resolution and re-size your picture
> with your favourite paint program.

  How is this different from using +a0.0?

-- 
#macro M(A,N,D,L)plane{-z,-9pigment{mandel L*9translate N color_map{[0rgb x]
[1rgb 9]}scale<D,D*3D>*1e3}rotate y*A*8}#end M(-3<1.206434.28623>70,7)M(
-1<.7438.1795>1,20)M(1<.77595.13699>30,20)M(3<.75923.07145>80,99)// - Warp -

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My fault. I did some tests and have to say that +a0.0 worked better than +a0.1 +r5,
even if it is way slower.

Anyway, IMHO, it's better to render at bigger resolution. This is a pretty common
technique to avoid many AA pitfalls.

--
Jonathan.

Home: http://digilander.iol.it/jrgpov

"Warp" <war### [at] tagpovrayorg> ha scritto nel messaggio
news:3ca6f7d6@news.povray.org...
> JRG <jrg### [at] hotmailcom> wrote:
> > If this doesn't work either, render at bigger resolution and re-size your picture
> > with your favourite paint program.
>
>   How is this different from using +a0.0?
>
> --
> #macro M(A,N,D,L)plane{-z,-9pigment{mandel L*9translate N color_map{[0rgb x]
> [1rgb 9]}scale<D,D*3D>*1e3}rotate y*A*8}#end M(-3<1.206434.28623>70,7)M(
> -1<.7438.1795>1,20)M(1<.77595.13699>30,20)M(3<.75923.07145>80,99)// - Warp -

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Warp wrote:
> 
> JRG <jrg### [at] hotmailcom> wrote:
> > If this doesn't work either, render at bigger resolution and re-size
> > your picture with your favourite paint program.
> 
>   How is this different from using +a0.0?

+a0.0 forces all pixels to go to the full depth.

+a0.1 at a higher resolution simulates a minimum depth of anti-aliasing,
without forcing full depth for all pixels.

A minimum aa depth might be a useful feature.

-- 
Rusty is rendering!

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JRG <jrg### [at] hotmailcom> wrote:
> Anyway, IMHO, it's better to render at bigger resolution. This is a pretty common
> technique to avoid many AA pitfalls.

  I still don't understand how that's different from using +a0.0.
(What +a0.0 does in practice is exactly what you propose: It kind of renders
an image at higher resultion and "scales" it down to the desired resolution.
This happens because it sends the extra rays for *each* pixel regardless of
what there is in the image; that's exactly the same as rendering at higher
resolution. You can control the extra resolution with +r.)

-- 
#macro N(D)#if(D>99)cylinder{M()#local D=div(D,104);M().5,2pigment{rgb M()}}
N(D)#end#end#macro M()<mod(D,13)-6mod(div(D,13)8)-3,10>#end blob{
N(11117333955)N(4254934330)N(3900569407)N(7382340)N(3358)N(970)}//  - Warp -

Post a reply to this message

John VanSickle <evi### [at] hotmailcom> wrote:
> +a0.0 forces all pixels to go to the full depth.

  Ie. exactly what rendering at higher resolution does.

> +a0.1 at a higher resolution simulates a minimum depth of anti-aliasing,
> without forcing full depth for all pixels.

  Yes, but rendering at higher resolution forces povray to shoot more rays
even though it wouldn't be necessary.

-- 
#macro N(D)#if(D>99)cylinder{M()#local D=div(D,104);M().5,2pigment{rgb M()}}
N(D)#end#end#macro M()<mod(D,13)-6mod(div(D,13)8)-3,10>#end blob{
N(11117333955)N(4254934330)N(3900569407)N(7382340)N(3358)N(970)}//  - Warp -

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In article <3ca75d03@news.povray.org>, Warp <war### [at] tagpovrayorg> 
wrote:

> > +a0.1 at a higher resolution simulates a minimum depth of anti-aliasing,
> > without forcing full depth for all pixels.
> 
>   Yes, but rendering at higher resolution forces povray to shoot more rays
> even though it wouldn't be necessary.

+a0.0 forces it to shoot all the rays for every pixel. Rendering at a 
higher resolution and resizing lets you control the minimum sampling 
density (making your objects more likely to be visible) while still 
taking advantage of adaptive sampling for faster rendering.
An additional "minimum samples" control would do the same thing, without 
the additional external step of reducing the final image in size, which 
will give different results with different programs.

-- 
Christopher James Huff <chr### [at] maccom>
POV-Ray TAG e-mail: chr### [at] tagpovrayorg
TAG web site: http://tag.povray.org/

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+a0.0 worked perfectly. Plus it fixed some artifacts I had with image maps.
Thanks a bunch!!


"Warp" <war### [at] tagpovrayorg> wrote in message
news:3ca678ed@news.povray.org...
> Chris Becker <cmb### [at] ritedu> wrote:
> > I have a very thin object that is not showing up correctly because some
> > pixels pick it up and others don't hence creating jaggies, even with
> > anti-aliasing. My question is, what do I adjust in anti-aliasing to
improve
> > this? And does increasing or decreasing the threshold provide for a
better
> > sample?
>
>   Try +a0.0 if it helps. (Note that it will slow down the rendering a
lot.)
>
> --
> #macro N(D)#if(D>99)cylinder{M()#local D=div(D,104);M().5,2pigment{rgb
M()}}
> N(D)#end#end#macro M()<mod(D,13)-6mod(div(D,13)8)-3,10>#end blob{
> N(11117333955)N(4254934330)N(3900569407)N(7382340)N(3358)N(970)}//  -
Warp -

Post a reply to this message