I've been fiddling with radiosity a lot more these last days and
weeks than I have before POV 3.5, but there are still
some things which elude me...

What are the actual options I need to set in order to get
smaller patches? I've rendered a scene with an emitting
sphere and a glass-sphere, and I got some caustics-like
effect (expected), but I've also got some brighter spots
way off the glass-sphere (not expected) and very visible
patches (not aimed for).

Simply put, the documentation does a fine job in explaining
the different options and their impact on samples, color
etc, but I don't get the overall method that POV uses.

So, can either someone point me to a section in the docs
which I've overseen, or explain some more in detail how it
works?

Thanks in advance,

Tim

--
Tim Nikias
Homepage: http://www.digitaltwilight.de/no_lights/index.html
Email: Tim### [at] gmxde

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Tim Nikias wrote:
> 
> [...]
> 
> So, can either someone point me to a section in the docs
> which I've overseen, or explain some more in detail how it
> works?

Maybe you have missed section 4.1?

Christoph

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

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Stupid me. I've read that section, but never really
thoroughly. More like: "What does count do?"

Reading it as a whole is better.

Sorry. I guess RTFM is applied here... ;-)


--
Tim Nikias
Homepage: http://www.digitaltwilight.de/no_lights/index.html
Email: Tim### [at] gmxde

> Maybe you have missed section 4.1?

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"Tim Nikias" <tim### [at] gmxde> wrote in news:3d804800@news.povray.org

> So, can either someone point me to a section in the docs
> which I've overseen, or explain some more in detail how it
> works?

basicly - using 
error 1 nearest 7 and count 30 gives smooth shadows but ignores detalis

error .5 nearest 8 and count 200 gives details but sometimes artefacts are 
visible

error .4 nearest 9 and count 1000 gives both details and smooth gradients 

(Basing on my lava scene in .b.i - but probaly typical scenes with normal 
light sources will look nice with count like 20,100,200, and recursion 4, 
instead of 8)


-- 
#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:
> 
> "Tim Nikias" <tim### [at] gmxde> wrote in news:3d804800@news.povray.org
> 
> > So, can either someone point me to a section in the docs
> > which I've overseen, or explain some more in detail how it
> > works?
> 
> basicly - using
> error 1 nearest 7 and count 30 gives smooth shadows but ignores detalis
> 
> error .5 nearest 8 and count 200 gives details but sometimes artefacts are
> visible
> 
> error .4 nearest 9 and count 1000 gives both details and smooth gradients
> 

No, you can't generalize what are good settings for radiosity.  This
enormously depends on scene geometry and textures.  I'd suggest trying the
parameters in 'rad_def.inc', they were designed to produce fairly fast and
often quite reasonable results and are a good starting point to test how
modifications improve things in an individual situation.

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:3D80F060.A080F575@gmx.de

> No, you can't generalize what are good settings for radiosity.  This
> enormously depends on scene geometry and textures. 

Yeap, as I said - this example was about my lava scene with is quite 
difficult because it uses no light_sources :)

-- 
#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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