so, any free time in your hands?  want to put that quad core to stress with
povray 3.7beta?  If you're, try the little scene below.  With +AM2 +A0.04 +J1.0
1024X768 on a P4 2.66, it just brought my PC to a crawl for the whole weekend!
It all began with a challenge in a brazilian forum, when some guy claimed this
scene:
http://200.213.105.41/greysilica/exemplos/cjcopojateado.png

took him 48 hours to render with Blender internal renderer.

Surely something was wrong, or so I thought.  Well, in the region between the
bottom of second row cups and the top of first row cups, render time was about
11 minutes a line!  It is all about refractions, normals and fresnel
reflections.  40 hours total on a P4 2.66 with povray 3.6.1...

I'm sure it's possible to optimize it with some no_image, no_shadow trickery
with doubles and no_reflection in the main cups, but I didn't thought of it
beforehand!


global_settings { max_trace_level 40 }

background { rgb 1 }

#local cup =
lathe { bezier_spline
48, //nr points
/* 0*/ <0, 2.8571826>, <174.28571, 2.8571826>, <197.14286,2.8571826>,
<197.14286,2.8571826>,
/* 1*/ <197.14286, 2.8571826>, <197.14286, 2.8571826>, <211.42857,-2.8571174>,
<228.57143,14.285683>,
/* 2*/ <228.57143, 14.285683>, <245.71429, 31.428583>, <242.85714,85.714283>,
<242.85714,85.714283>,
/* 3*/ <242.85714, 85.714283>, <242.85714, 85.714283>, <265.71429,80.000003>,
<291.42857,105.71428>,
/* 4*/ <291.42857, 105.71428>, <317.14286, 131.42857>, <308.57143,108.57143>,
<308.57143,185.71428>,
/* 5*/ <308.57143, 185.71428>, <308.57143, 262.85714>, <308.57143,742.85714>,
<308.57143,742.85714>,
/* 6*/ <308.57143, 742.85714>, <308.57143, 742.85714>, <317.14286,737.14285>,
<308.57143,754.28571>,
/* 7*/ <308.57143, 754.28571>, <300, 771.42857>, <288.57143,780>,
<280,768.57143>,
/* 8*/ <280, 768.57143>, <271.42857, 757.14285>, <294.28571,165.71428>,
<277.14286,148.57143>,
/* 9*/ <277.14286, 148.57143>, <260, 131.42857>, <231.42857,131.42857>,
<217.14286,105.71428>,
/* 10*/ <217.14286, 105.71428>, <202.85714, 80.000003>, <205.71429,54.285713>,
<185.71429,45.714283>,
/* 11*/ <185.71429, 45.714283>, <165.71429, 37.142883>, <2.8571429,2.8571826>,
<0,2.8571826>

sturm
scale y*.8
scale 1/1000
interior { ior 1.5 }
hollow
}

#macro tex( col )
pigment { rgb col }
normal { bumps .1 scale .002 }
finish { ambient .01 diffuse .4 brilliance 1.2
specular .97 roughness .02
metallic .1
reflection { .2,.9 metallic .1 fresnel on exponent 1 }
conserve_energy
}
#end

union {
plane { y 0 pigment { rgb 1 } finish { ambient .2 diffuse .6 } }
object { cup translate 0 tex( <.7,.8,1,.8,.1> ) }
object { cup translate z*.7 tex( <.9,.86,.4,.8,.1> ) }
object { cup translate z*(.7+1.3) tex( <1,.96,.84,.8,.1> ) }
object { cup translate x*.7 tex(<1,1,1,.8,.1> ) }
object { cup translate x*.7+z*.7 tex(<.96,1,.67,.8,.1> )}
object { cup translate x*.7+z*.7*2 tex(<.7,1,.7,.8,.1> ) }
object { cup translate -x*.7 tex(<1,.6,.6,.1,.8> ) }
object { cup translate -x*.7+z*(.0+1.3) tex(<.5,.5,.8,.1,.8> ) }
object { cup translate -x*.7*2+z*(-.7+1.3) tex(<.7,1,.94,.1,.8> ) }
light_source { 1.6*(4-z*8) 1.2 }

rotate -x*30
translate z*2.6-y/3+x*.1
}

light_source { -z*8 .7 shadowless }

camera { angle 55
//aperture .04 blur_samples 60 confidence 1 focal_point y/3+z*2
}

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Attachments:
Download 'multiple_cups.png' (588 KB)

Preview of image 'multiple_cups.png'

Hmm strange, why is it letting you pass a 4D vector to 'rgb'? Is the 
fourth term filter or transmit? Does rgb really behave as rgbft?

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> Hmm strange, why is it letting you pass a 4D vector to 'rgb'?

Wait, that's a 5D vector...

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z*2.6-y/3+x*.1 instead of <0.1, -1/3, 2.6>? This isn't the obfuscated 
code contest, you know :)

I'm trying to modify the scene so that the camera gets rotated, instead 
of the whole scene. And taking that lightsource outside the union. My 
final goal is a camera rotate y*360*clock that looks good. It's not 
turning out so easy...

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Nice!
Whew!
I couldn't do that. I'm lacking patience. :)
And it would last more than 40 hours with my PC. ;)
How much time would it need, when these cups would be filled with different
juices?
The final result isn't a waste of time!!

Regards
                 bluetree

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Very nice way to waste time...
Blender image has perhaps better lights, but I like a lot your cups.
;-)
Paolo

 >nemesis wrote:
> so, any free time in your hands?  want to put that quad core to stress with
> povray 3.7beta?  If you're, try the little scene below.  With +AM2 +A0.04 +J1.0
> 1024X768 on a P4 2.66, it just brought my PC to a crawl for the whole weekend!
> It all began with a challenge in a brazilian forum, when some guy claimed this
> scene:
> http://200.213.105.41/greysilica/exemplos/cjcopojateado.png
> 
> took him 48 hours to render with Blender internal renderer.
> 
> Surely something was wrong, or so I thought.  Well, in the region between the
> bottom of second row cups and the top of first row cups, render time was about
> 11 minutes a line!  It is all about refractions, normals and fresnel
> reflections.  40 hours total on a P4 2.66 with povray 3.6.1...
> 
> I'm sure it's possible to optimize it with some no_image, no_shadow trickery
> with doubles and no_reflection in the main cups, but I didn't thought of it
> beforehand!
> 
> 
> global_settings { max_trace_level 40 }
> 
> background { rgb 1 }
> 
> #local cup =
> lathe { bezier_spline
> 48, //nr points
> /* 0*/ <0, 2.8571826>, <174.28571, 2.8571826>, <197.14286,2.8571826>,
> <197.14286,2.8571826>,
> /* 1*/ <197.14286, 2.8571826>, <197.14286, 2.8571826>, <211.42857,-2.8571174>,
> <228.57143,14.285683>,
> /* 2*/ <228.57143, 14.285683>, <245.71429, 31.428583>, <242.85714,85.714283>,
> <242.85714,85.714283>,
> /* 3*/ <242.85714, 85.714283>, <242.85714, 85.714283>, <265.71429,80.000003>,
> <291.42857,105.71428>,
> /* 4*/ <291.42857, 105.71428>, <317.14286, 131.42857>, <308.57143,108.57143>,
> <308.57143,185.71428>,
> /* 5*/ <308.57143, 185.71428>, <308.57143, 262.85714>, <308.57143,742.85714>,
> <308.57143,742.85714>,
> /* 6*/ <308.57143, 742.85714>, <308.57143, 742.85714>, <317.14286,737.14285>,
> <308.57143,754.28571>,
> /* 7*/ <308.57143, 754.28571>, <300, 771.42857>, <288.57143,780>,
> <280,768.57143>,
> /* 8*/ <280, 768.57143>, <271.42857, 757.14285>, <294.28571,165.71428>,
> <277.14286,148.57143>,
> /* 9*/ <277.14286, 148.57143>, <260, 131.42857>, <231.42857,131.42857>,
> <217.14286,105.71428>,
> /* 10*/ <217.14286, 105.71428>, <202.85714, 80.000003>, <205.71429,54.285713>,
> <185.71429,45.714283>,
> /* 11*/ <185.71429, 45.714283>, <165.71429, 37.142883>, <2.8571429,2.8571826>,
> <0,2.8571826>
> 
> sturm
> scale y*.8
> scale 1/1000
> interior { ior 1.5 }
> hollow
> }
> 
> #macro tex( col )
> pigment { rgb col }
> normal { bumps .1 scale .002 }
> finish { ambient .01 diffuse .4 brilliance 1.2
> specular .97 roughness .02
> metallic .1
> reflection { .2,.9 metallic .1 fresnel on exponent 1 }
> conserve_energy
> }
> #end
> 
> union {
> plane { y 0 pigment { rgb 1 } finish { ambient .2 diffuse .6 } }
> object { cup translate 0 tex( <.7,.8,1,.8,.1> ) }
> object { cup translate z*.7 tex( <.9,.86,.4,.8,.1> ) }
> object { cup translate z*(.7+1.3) tex( <1,.96,.84,.8,.1> ) }
> object { cup translate x*.7 tex(<1,1,1,.8,.1> ) }
> object { cup translate x*.7+z*.7 tex(<.96,1,.67,.8,.1> )}
> object { cup translate x*.7+z*.7*2 tex(<.7,1,.7,.8,.1> ) }
> object { cup translate -x*.7 tex(<1,.6,.6,.1,.8> ) }
> object { cup translate -x*.7+z*(.0+1.3) tex(<.5,.5,.8,.1,.8> ) }
> object { cup translate -x*.7*2+z*(-.7+1.3) tex(<.7,1,.94,.1,.8> ) }
> light_source { 1.6*(4-z*8) 1.2 }
> 
> rotate -x*30
> translate z*2.6-y/3+x*.1
> }
> 
> light_source { -z*8 .7 shadowless }
> 
> camera { angle 55
> //aperture .04 blur_samples 60 confidence 1 focal_point y/3+z*2
> }
> 
> 
> ------------------------------------------------------------------------
>

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nemesis nous apporta ses lumieres en ce 2008/01/27 20:20:
> so, any free time in your hands?  want to put that quad core to stress with
> povray 3.7beta?  If you're, try the little scene below.  With +AM2 +A0.04 +J1.0
> 1024X768 on a P4 2.66, it just brought my PC to a crawl for the whole weekend!
> It all began with a challenge in a brazilian forum, when some guy claimed this
> scene:
> http://200.213.105.41/greysilica/exemplos/cjcopojateado.png
> 
> took him 48 hours to render with Blender internal renderer.
> 
> Surely something was wrong, or so I thought.  Well, in the region between the
> bottom of second row cups and the top of first row cups, render time was about
> 11 minutes a line!  It is all about refractions, normals and fresnel
> reflections.  40 hours total on a P4 2.66 with povray 3.6.1...
> 
> I'm sure it's possible to optimize it with some no_image, no_shadow trickery
> with doubles and no_reflection in the main cups, but I didn't thought of it
> beforehand!
> 
You have multiple reflections and refractions. That mean that you have tons of 
rays to compute. Add the aa and the small bumps, you need lot of subsampling = 
lot of time.
Try adding adc_bailout 0.01 in the global_settings.
It will cause a small decrease in quality that can go unnoticed, but will 
accelerate things as the ray tracing will often stop much earlier.

-- 
Alain
-------------------------------------------------
The strongest reason for the people to retain the right to keep and bear
arms is, as a last resort, to protect themselves against tyranny in
government.
Thomas Jefferson

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seemingly, yes.  It gives a "suspicious" warning at the console output. 
It's rgbft.  I think I should've put some more transmit and a little less 
filter.  Hmm, I suppose 1 filter and 1 transmit do not work right:  the 
color became quite bizarre when I tried...  I also think the original 
image had a lot more diffuse and ambient as well...

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Attachments:
Download 'us-ascii' (1 KB)

> 
> seemingly, yes.  It gives a "suspicious" warning at the console output. 
>  It's rgbft.  I think I should've put some more transmit and a little 
> less filter.  Hmm, I suppose 1 filter and 1 transmit do not work right: 
>  the color became quite bizarre when I tried...  I also think the 
> original image had a lot more diffuse and ambient as well...

I heard (filter + transmit) should be <= 1 for things to look correctly.

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Alain escribió:
> You have multiple reflections and refractions. That mean that you have 
> tons of rays to compute. Add the aa and the small bumps, you need lot of 
> subsampling = lot of time.
> Try adding adc_bailout 0.01 in the global_settings.
> It will cause a small decrease in quality that can go unnoticed, but 
> will accelerate things as the ray tracing will often stop much earlier.
> 

He also has focal blur (commented out on the scene, but looks like the 
image has it).

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