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17 Jun 2024 06:28:11 EDT (-0400)
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From: alphaQuad
Subject: Re: waste of time!
Date: 28 Jan 2008 21:40:00
Message: <web.479e918eb082306e3ffee9290@news.povray.org>
"nemesis" <nam### [at] gmailcom> wrote:

> hmm, 32 minutes at, what, 640x480?  and no supersampling antialiasing?  Besides,
> there doesn't even seem to be any shadows...
>
> I'll play with it, but first I need to come up with a better bezier curve... :)

that was [512x384, AA 0.3] from res menu / 750mhz single CPU
shadows are faint but visible

and my edits:code for previous img
(radiosity more fully explained)

#include "echo.inc"
global_settings {
  max_trace_level 10
  assumed_gamma 1.0

  adc_bailout 0.111     // larger number = faster
  // for HDR image file creation adc_bailout 1/1e6 = 0.000001

  // global setting adc_bailout keyword followed by float value to specify
  // the point at which a ray's contribution is considered insignificant
  // The default value is 1/255, or approximately 0.0039, since a change smaller
than that could not be visible in a 24 bit image.
  // Setting adc_bailout to 0 will disable ADC
#if (1)
  radiosity {
    // controls radiosity pre-trace gathering step
    pretrace_start 0.08 //default 0.08
    pretrace_end 0.01   // default 0.04
    //range 0.0 and 1.0 which specifies the size of the blocks in the
    // mosaic_preview as a percentage of the image size

    count 40 // The integer number of rays that are sent out whenever a new
radiosity value has to be calculated is given by count.
    // A value of 35 is the default, the maximum is 1600.
    // When this value is too low, the light level will tend to look a little
bit blotchy, as if the surfaces were
    // slightly warped. If this is not important to your scene (as in the case
that you have a bump map or if you have a strong texture)
    // then by all means use a lower number.

    // minimum number of old ambient values blended together to create a new
interpolated value. The total number blended will
    // vary depending on error_bound. All previous values that fit within the
specified error_bound will be used in the average.
    nearest_count 8
    // lower than 4, things can get pretty patchy. Must be no more than 20,
since that is the size of the array allocated.
    // default 5

    error_bound 1.5  // default 1.8 is good for a smooth general lighting
effect.
    // Lower values are more accurate, but will strongly increase the danger of
artifacts
    // and therefore require higher count. You can use values even lower than
0.1 but both render time and memory
    // use can become extremely high then.

    recursion_limit 3   // default 3
    // recursion levels are used to calculate the diffuse inter-reflection

    low_error_factor .5
    // The low_error_factor is a float tuning value which sets the amount that
the error bound is dropped during the preliminary image passes. If your low
error factor is 0.8 and your error bound is set to 0.4 it will really use an
error bound of 0.32 during the first passes and 0.4 on the final pass.
    // default 0.5

    gray_threshold 0.01
    // The gray_threshold float value grays it down a little, to make your scene
more believable. A value of .6 means to calculate the ambient
    // value as 60% of the equivalent gray value calculated, plus 40% of the
actual value calculated. At 0%, this feature does nothing. At 100%, you always
get white/gray ambient light, with no hue.
    // default 0.0

    minimum_reuse 0.0095
    // This sets a minimum bound for the reuse. If this value is too low, (which
it should be in theory) rendering gets slow, and inside corners can get a little
grainy.
    // If it is set too high, you do not get the natural darkening of
illumination near inside edges, since it reuses. At values higher than 2% you
start getting more just plain errors, like reusing the illumination of the open
table underneath the apple. Remember that this is a unit less ratio.
    // default 0.015.

    brightness 0.95 // default 1.0
    // specifies a float value
    // ambient_light in a non-Radiosity scene    //default <1,1,1>

    // Megapov 1.1
    // randomize on

    // Radiosity estimation affected by normals
    normal on
    media on
  }   #end
}

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 .6 } finish { ambient 0 diffuse 1 } }
//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,.4,.4,.95,.1> ) }
object { cup translate -x*.7+z*(.0+1.3) tex(<.3,.3,.9,.8,.1> ) }
object { cup translate -x*.7*2+z*(-.7+1.3) tex(<.7,1,.94,.8,.1> ) }
translate -z*0.8
}

light_source {
   <0,0,10>
   4.5
   area_light
   x,y,4,4
   circular orient jitter
}
camera {
   location <0,5,-9>
   look_at <-0.3,.6,0>
   angle 20
}


streamlined way to see a value in message pane:
echo(str) / echof(float) / echov(3d_vector)
%%%%%%%%%%%%%%%%%%%%%%%%%%%% echo.inc %%%%%%%%%%%%%%%%%%%%%%%%
#macro echo(Str)
    #if (1)
        #debug Str
    #end
#end
#macro echof(f)
echo(concat("\n*********** ",str(f,2,5)," *********** "))
#end
#macro echov(V)
echo(concat("\n********** <",str(V.x,2,5),",",str(V.y,2,5),",",str(V.z,2,5),">
***********"))
#end


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From: alphaQuad
Subject: Re: waste of time!
Date: 28 Jan 2008 21:50:00
Message: <web.479e9430b082306e3ffee9290@news.povray.org>
I should add:

want to know that value before rendering is done?

do it twice:
echov(<1,1,1>)
echov(<1,1,1>)

strange kwirk in #debug


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From: nemesis
Subject: Re: waste of time!
Date: 28 Jan 2008 22:40:01
Message: <web.479e9f59b082306e6dd25c20@news.povray.org>
"alphaQuad" <alp### [at] earthlinknet> wrote:
> that was [512x384, AA 0.3] from res menu / 750mhz single CPU

AA 0.3 is not supersampling AA, which is the best.  command-line:  +AM2 +A0.04
or lower...

> shadows are faint but visible

hmm, you put the standard radiosity there.  Given the white background, it
almost made the shadows disappear...


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From: alphaQuad
Subject: Re: waste of time!
Date: 29 Jan 2008 00:10:01
Message: <web.479eb4d1b082306ec29b7d970@news.povray.org>
"nemesis" <nam### [at] gmailcom> wrote:
> "alphaQuad" <alp### [at] earthlinknet> wrote:
> > that was [512x384, AA 0.3] from res menu / 750mhz single CPU
>
> AA 0.3 is not supersampling AA, which is the best.  command-line:  +AM2 +A0.04
> or lower...
>
> > shadows are faint but visible
>
> hmm, you put the standard radiosity there.  Given the white background, it
> almost made the shadows disappear...


with command line +AM2 +A0.04 looking like 40 minutes for one cup
(hard pressed to see a difference without)

here: 12 minute cup (+AM2 +A0.04 NOT USED)

adjusted in this manner (except cup back to orig color filter 1)
object { cup translate -x*.7 tex(<1,.6,.6,1,.1> ) }

one cup 'til effects acheived:



plane { y 0 pigment { rgb .7 } finish { ambient 0 diffuse 1 } }

background { rgb .2 }
#declare lv = <-5,5,-5>; // <0,1,0> cant work here
#declare arraylen = 1;

#declare _x = vnormalize(vcross(y,lv))*arraylen;
#declare _y = vnormalize(vcross(lv,_x))*arraylen;
light_source {
   lv
   1
   area_light
   _x,_y,4,4
   circular orient jitter

}
camera {
   location <0,5,-9>
   look_at <-0.3,.6,0>
   angle 20
}


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Attachments:
Download 'glasses5.png' (38 KB)

Preview of image 'glasses5.png'
glasses5.png


 

From: alphaQuad
Subject: Re: waste of time!
Date: 29 Jan 2008 03:35:01
Message: <web.479ee489b082306ec29b7d970@news.povray.org>
Type 2, adaptive and recursive, and a threshold of .04 has super-sampled the
bumps right out, with a render time diff of 3.5 hours.

I was thinking about resetting bailout to 24bit (from .111 to 1/256) next to see
if there is a visible difference, but if bumps should be kept, it should be
compared glasses5.png as opposed to this one, 6.

Maybe bigger bumps are needed with super-sampling? or removed from tex() for
additional speed.

>I'll play with it, but first I need to come up with a better bezier curve... :)
hope I get to see it.


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Attachments:
Download 'glasses6.png' (36 KB)

Preview of image 'glasses6.png'
glasses6.png


 

From: Christian Froeschlin
Subject: Re: waste of time!
Date: 29 Jan 2008 08:37:24
Message: <479f2c14@news.povray.org>
Jan Dvorak wrote:

> Nicolas Alvarez napsal(a):
>>
>> I heard (filter + transmit) should be <= 1 for things to look correctly.
> 
> f+t <= 1
> f   >  0
> t   >  0
> 
> Did I forget something?

Reflection would also play into the equations.

The keyword "conserve_energy" can be useful.


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From: Alain
Subject: Re: waste of time!
Date: 29 Jan 2008 09:29:05
Message: <479f3831$1@news.povray.org>
Alain nous apporta ses lumieres en ce 2008/01/28 15:06:
> 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!
>>
> Just rendered here with 3.7.
> LOT faster with +am2 +a0.3 at 1360*1024 AMD Athlon TBird 1400MHz.
> Added adc_bailout 0.013.
> Render time: 1:48:15.
> Only thing, your glasses look much darker.
> 
New render with +a0.1. Render time of 8:54:55 with nothing else changed. 
Imperceptible difference.

So, what's killing you is the aa with the micro normals.
Increasing the resolution will have the benefit of reducing the aa work, 
increasing the chance that adjacent pixels difference to be under the aa treshold.

-- 
Alain
-------------------------------------------------
A clear conscience is usually the sign of a bad memory.


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From: nemesis
Subject: Re: waste of time!
Date: 29 Jan 2008 09:56:54
Message: <479f3eb6$1@news.povray.org>
alphaQuad wrote:
> Maybe bigger bumps are needed with super-sampling? or removed from tex() for
> additional speed.

so thinks Alain in a message below.

>> I'll play with it, but first I need to come up with a better bezier curve... :)
> hope I get to see it.

for some reason, my bezier curves are not getting as smooth as I 
expected.  I'll update the scene when I get a smooth curve... you guys 
of course can play with it at will... I'm actually putting various 
speed/parameter variables all around...


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From: Alain
Subject: Re: waste of time!
Date: 29 Jan 2008 10:00:24
Message: <479f3f88$1@news.povray.org>
Christian Froeschlin nous apporta ses lumieres en ce 2008/01/29 08:40:
> Jan Dvorak wrote:
> 
>> Nicolas Alvarez napsal(a):
>>>
>>> I heard (filter + transmit) should be <= 1 for things to look correctly.
>>
>> f+t <= 1
>> f   >  0
>> t   >  0
>>
>> Did I forget something?
> 
> Reflection would also play into the equations.
> 
> The keyword "conserve_energy" can be useful.
 From the original scene: (plus my comments)
#macro tex( col )
pigment { rgb col }// this generate a "suspicious expression after rgb" warning
normal { bumps .1 scale .002 }// micro normal. Killer with high aa settings.
finish { ambient 0 diffuse .4 brilliance 1.2
specular .97 roughness .02
metallic .1
reflection { .2,.9 metallic .1 fresnel on exponent 1 }
conserve_energy
}
#end

conserve_energy is there.

-- 
Alain
-------------------------------------------------
Grandchildren are God's reward for not killing your own.


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From: nemesis
Subject: Re: waste of time!
Date: 29 Jan 2008 10:47:34
Message: <479f4a96$1@news.povray.org>
Christian Froeschlin wrote:
> The keyword "conserve_energy" can be useful.

it's there.  And taking it away seems to produce a far more brighter 
picture, although as unrealistic as the original...


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