I have decided to do a series of glowing boxes, I dont know if I stole 
this from anyone, if so, please let me know, and I apologize.  Here is a 
partial rendering of the first one, with radiosity off (looks better 
with it on, duh) and some artifacts that I believe are from AA.  If you 
can tell me how to fix that, I would be quite thankful.  Its currently 
AA adaptive .4 threshold, level 5 recursion, and .1 jitter.  I have a 
lot going one because it was highly aliased, espescially at large 
resolutions.  You can notice it at the edge facing the camera, the line 
between dark and light is not straigt.

Thanks in advace.
Matthew Pace

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Attachments:
Download 'box.png' (32 KB)

Preview of image 'box.png'

> some artifacts that I believe are from AA.  If you
> can tell me how to fix that, I would be quite thankful.  Its currently
> AA adaptive .4 threshold, level 5 recursion, and .1 jitter.

I think the area of the box that you mentioned is *not* being AA'ed, since
it consists of two shades of grey which are very close to each other (less
than .4). Try reducing your AA threshold (try .2 for starters) and see if
the problem goes away. (It should at least be reduced once you get the
threshold low enough.)

By the way, you probably don't need a recursion level as high as 5. I think
2 or 3 would do the trick.

 - Slime
 [ http://www.slimeland.com/ ]

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"Matthew Pace" <mat### [at] earthlinknet> wrote in message
news:matthewpace-C0B659.23235701022004@news.povray.org...

If you are going to work on such a simple idea, then you really need to
concentrate on not being so sloppy about it. This picture would be
helped by more attention to the proportions of the cube segments.

 -Shay

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mat### [at] earthlinknet news:matthewpace-
C0B659.23235701022004@news.povray.org

> Its currently 
> AA adaptive .4 threshold, level 5 recursion, and .1 jitter.

It's better to lower threshold i.e. try treshold 0.03 (recursion 3, method 
1 or 2, jitter mabe off, or .1-.5)



-- 
#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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"Shay" <sah### [at] simcopartscom> wrote in news:401e81b6@news.povray.org:

> 
> If you are going to work on such a simple idea, then you really need to
> concentrate on not being so sloppy about it. This picture would be
> helped by more attention to the proportions of the cube segments.
> 

Different strokes for different folks.  That was one of the interesting 
things about it for me.  Otherwise it is just another rubik's cube.  


-- 
Tom
_________________________________
The Internet Movie Project
http://www.imp.org/

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In article <401e81b6@news.povray.org>, "Shay" <sah### [at] simcopartscom> 
wrote:

> "Matthew Pace" <mat### [at] earthlinknet> wrote in message
> news:matthewpace-C0B659.23235701022004@news.povray.org...
> 
> If you are going to work on such a simple idea, then you really need to
> concentrate on not being so sloppy about it. This picture would be
> helped by more attention to the proportions of the cube segments.
> 
>  -Shay
> 
> 


I didnt want them to be equally sized, otherwise I would have done some 
basic addition and subtraction to measure them out.  This was not 
sloppiness, and I am sorry you do not like the way I made it.  If you 
look closely, you can see that I did not even cut through the cube, but 
rather indented it with CSG and some cylinders.

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"Matthew Pace" <mat### [at] earthlinknet> wrote in message
news:matthewpace-79C3D0.15481402022004@news.povray.org...
|
| This was not sloppiness, and I am sorry you do not like the way
| I made it.

Looks like I was mistaken. I apologize, but certainly you can understand
my assumption.

Someone said once about abstract painters something to the effect of
their being more realist than "realist" painters, as the abstract
painters are presenting the reality of paint rather than attempting to
create an illusion. Carried over to cg, this paradigm legitimizes the
purposeful use of hard shadows, perfect corners, and the substitution of
ambience for glow.

I find this idea interesting and am therefore discouraged to see that so
many technically simple cg pictures carry tell-tale marks of sloppiness
like unscaled textures and arbitrarily placed or proportioned objects.
Of course there are times like this one when a person's intentional
design for his picture appears arbitrary when it is not. There are even
times when a person consciously decides that an element of his picture
truly is arbitrary and therefore gives no concern to that element.

Enjoy making the rest of your series.

 -Shay

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Matthew Pace wrote:
> I have decided to do a series of glowing boxes, I dont know if I stole 
> this from anyone, if so, please let me know, and I apologize.  Here is a 
> partial rendering of the first one, with radiosity off (looks better 
> with it on, duh) and some artifacts that I believe are from AA.  If you 
> can tell me how to fix that, I would be quite thankful.  Its currently 
> AA adaptive .4 threshold, level 5 recursion, and .1 jitter.  I have a 
> lot going one because it was highly aliased, espescially at large 
> resolutions.  You can notice it at the edge facing the camera, the line 
> between dark and light is not straigt.

You seem to have a poor understanding of the AA parameters, maybe I can 
help...

The threshold defines how much difference there has to be between two 
pixels before POV-Ray will attempt to antialias them, treating each 
pixel as having RGBvalues between 0 and 1; this value can range from 0 
(AA everything except areas of no changes whatsoever) to 3 (only AA 
divisions between pure white and pure black - in effect, nothing). A 
good value to use for this while testing (if for some reason you're 
testing with AA on) is .2 or .3, which is enough to get the effect of AA 
but not enough to guarantee smoothness. For final renders, consider 
using .1 or less.

The recursion defines how closely POV-Ray looks for edges; the higher 
the recursion, the more supersamples it takes in order to define edges 
and/or small details. In actual practice, a value of 2 is plenty for 
test work, and anything above 4 is likely to be a waste; if you're not 
getting enough detail at 4, you're probably better off rendering at a 
higher resolution.

Jitter jitters the supersamples, essentially adding a small amount of 
noise to antialiased areas, and should probably be avoided as a general 
rule (IMO). In your case, I would say that jitter is responsible for the 
"artifacts" you describe. Try setting it to 0.

You might also consider moving the camera or objects slightly so that 
the division between the front faces falls along natural pixel 
boundaries, if having the antialiased edge there REALLY bothers you.

-Xplo

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>whole bunch of info

> -Xplo
> 

Thanks a lot!

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In article <40212d0f@news.povray.org>, "Shay" <sah### [at] simcopartscom> 
wrote:

> "Matthew Pace" <mat### [at] earthlinknet> wrote in message
> news:matthewpace-79C3D0.15481402022004@news.povray.org...
> |
> | This was not sloppiness, and I am sorry you do not like the way
> | I made it.
> 
> Looks like I was mistaken. I apologize, but certainly you can understand
> my assumption.
> 
> Someone said once about abstract painters something to the effect of
> their being more realist than "realist" painters, as the abstract
> painters are presenting the reality of paint rather than attempting to
> create an illusion. Carried over to cg, this paradigm legitimizes the
> purposeful use of hard shadows, perfect corners, and the substitution of
> ambience for glow.
> 
> I find this idea interesting and am therefore discouraged to see that so
> many technically simple cg pictures carry tell-tale marks of sloppiness
> like unscaled textures and arbitrarily placed or proportioned objects.
> Of course there are times like this one when a person's intentional
> design for his picture appears arbitrary when it is not. There are even
> times when a person consciously decides that an element of his picture
> truly is arbitrary and therefore gives no concern to that element.
> 
> Enjoy making the rest of your series.
> 
>  -Shay
> 
> 
> 

Interesting, do not worry about it, no one can see what an artist is 
thinking when they make something, and of course I understand

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