Hi folks,

I recently came across Paul Nylander's website at http://www.bugman123.com.
Marvellous images of 3D fractals rendered with Mathematica.
Exceptional rendering times and amazing images!
He also published some code to render Mandelbulbs in Povray.

Here is SDL for one of the Mandelbulbs:

// Mandelbulb - power 4 - Believe me the power 6 is a vision of hell!

// Adapted from original function for power 8 by Paul Nylander at
http://www.bugman123.com;
// Trace time on an AMD Ryzen7 Eight Core using 16 threads: 7 h 54 min with
max_gradient 1000
// Trace time on an AMD Ryzen7 Eight Core using 16 threads: 2 h 34 min with
max_gradient 200
-------------------------------------------------------
#version 3.7;
global_settings { assumed_gamma 2.2 }

// #include "colors.inc"
// #include "textures.inc"
// #include "math.inc"

camera{
 location <1.75,4,-5.5>
 look_at <0.0, 0.0, 0.0>
 up y
 sky y
 angle 25
}


light_source{<-20.00, 30.00, -20.00> color rgb < 1.0, 0.498039, 0.0 >} // color
Coral
light_source{<20.00, -30.00, 0.00> color rgb < 0.847059, 0.847059, 0.74902 >} //
color Wheat

#declare n=4;

#declare f=function(i,x,y,z,xc,yc,zc) {select(i>0 & x*x+y*y+z*z<4, 0,
sqrt(x*x+y*y+z*z),

f(i-1,pow(x*x+y*y+z*z,n/2)*cos(n*atan2(y,x))*cos(n*atan2(z,sqrt(x*x+y*y)))+xc,
        pow(x*x+y*y+z*z,n/2)*sin(n*atan2(y,x))*cos(n*atan2(z,sqrt(x*x+y*y)))+yc,
        -pow(x*x+y*y+z*z,n/2)*sin(n*atan2(z,sqrt(x*x+y*y)))+zc,xc,yc,zc))};

isosurface{
 function{f(24,0,0,0,x,y,z)}
 threshold 2
 max_gradient 200 // found by Povray: 33566
 contained_by{sphere{0,1.5}}
 pigment{rgb 1}
}
//end
----------------------------------------------------------------
But a word of warning before you start:
DO NOT ACTIVATE any INC-FILE! When I did Povray crashes as soon as I start
rendering!

Has anyone an idea why Povray crashes?

There is only a warning in the Message Window that says something like
'iterations are not allowed in this function'.

Happy tracing - and when you do: grab a big snack and a big mug of coffee before
you do!

Droj

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Attachments:
Download 'mandelbulb_power4.png' (1117 KB)

Preview of image 'mandelbulb_power4.png'

On 07/05/2024 23:41, Droj wrote:
> 
> // Adapted from original function for power 8 by Paul Nylander at
> http://www.bugman123.com;
> // Trace time on an AMD Ryzen7 Eight Core using 16 threads: 7 h 54 min with
> max_gradient 1000
> // Trace time on an AMD Ryzen7 Eight Core using 16 threads: 2 h 34 min with
> max_gradient 200
> -------------------------------------------------------

Hi, Droj !

Very interesting - thanks for sharing.
I've rendered this 800x600 image with max_gradient=1000 (No other
parameters was changed) on Intel(R) Xeon(R) CPU E5-2690 v2 @ 3.00GHz
(40 cores) for 2 min 19 sec and can't figure out how to get make it more
detailed.

Any suggestions, please !
--
YB

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Attachments:
Download 'fract_01.png' (288 KB)

Preview of image 'fract_01.png'

On 07/05/2024 23:41, Droj wrote:
> 
> // Adapted from original function for power 8 by Paul Nylander at
> http://www.bugman123.com;
> // Trace time on an AMD Ryzen7 Eight Core using 16 threads: 7 h 54 min with
> max_gradient 1000
> // Trace time on an AMD Ryzen7 Eight Core using 16 threads: 2 h 34 min with
> max_gradient 200
> -------------------------------------------------------

Hi, Droj !

Very interesting - thanks for sharing.
I've rendered this 800x600 image with max_gradient=1000 (No other
parameters was changed) on Intel(R) Xeon(R) CPU E5-2690 v2 @ 3.00GHz
(40 cores) for 2 min 19 sec and can't figure out how to make it more
detailed.

Any suggestions, please !
-- 
YB

Post a reply to this message

Attachments:
Download 'fract_01.png' (288 KB)

Preview of image 'fract_01.png'

On 07/05/2024 23:41, Droj wrote:
> // Mandelbulb - power 4 - Believe me the power 6 is a vision of hell!

Agree with you - sometimes it looks horrible ...
--------------------------------------------------------------------
camera{location <-2.5,5,5> look_at <-0.5,0,0.3> up z sky z angle 25}
light_source{20*z,1}

#declare f=function(i,x,y,z,xc,yc,zc) {select(i>0 & x*x+y*y+z*z<4, 0, 
sqrt(x*x+y*y+z*z), 
f(i-1,(x*x-y*y)*(1-z*z/(x*x+y*y))+xc,2*x*y*(1-z*z/(x*x+y*y))+yc,-2*z*sqrt(x*x+y*y)+zc,xc,yc,zc))};

isosurface{function{f(24,x,y,z,x,y,z)} threshold 0.5 max_gradient 1000 
contained_by{sphere{<-0.5,0,0>,2}} pigment{rgb 1}}
--------------------------------------------------------------------

--
YB.

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Attachments:
Download 'fract_02.png' (163 KB) Download 'fract_02_1.png' (117 KB)

Preview of image 'fract_02.png'

Preview of image 'fract_02_1.png'

yesbird <sya### [at] gmailcom> wrote:

>
> Very interesting - thanks for sharing.
> I've rendered this 800x600 image with max_gradient=1000 (No other
> parameters was changed) on Intel(R) Xeon(R) CPU E5-2690 v2 @ 3.00GHz
> (40 cores) for 2 min 19 sec and can't figure out how to get make it more
> detailed.
>
> Any suggestions, please !
> --
> YB

Hi yesbird

as I can see you have no problem with the rendering time as I have.

You can increase max_gradient.
When I rendered it the max_gradient Povray found was 33566.

So give it a go.

Droj

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On 09/05/2024 16:23, Droj wrote:
> So give it a go.

Hi, Droj.

Thank you, I will try.
--
YB

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On 09/05/2024 16:23, Droj wrote:
> When I rendered it the max_gradient Povray found was 33566.

It took 15m59,185s for rendering with max_gradient=33566, and n=6,
but I see, that your image looks more smooth and pretty.
What's the secret ? Antialiasing, maybe ... Could you please post
all rendering parameters ?

> // Mandelbulb - power 4 - Believe me the power 6 is a vision of hell!

This teddy bear don't looks like real daemon, but some sort of inferno
is present, no doubt ...
--
YB

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Attachments:
Download 'mand_pow_6_1600x1200.png' (1117 KB)

Preview of image 'mand_pow_6_1600x1200.png'

yesbird <sya### [at] gmailcom> wrote:

> It took 15m59,185s for rendering with max_gradient=33566, and n=6,
> but I see, that your image looks more smooth and pretty.
> What's the secret ? Antialiasing, maybe ... Could you please post
> all rendering parameters ?

Hi YB
Oh man you make me weep! 16 min with max_gradient=33566 ... if I try my image
will be finished next week.
Here are the settings of the ini-file I use:
-----------------
Width = 1600
Height = 1200
Antialias = On
Sampling_Method = 1
Antialias_Threshold = 0.0010
Jitter = Off
Antialias_Depth = 9
Output_To_File = On
Output_File_Type = N
Display = On
Verbose = Off
Quality = 11
Input_File_Name =
Output_File_Name =
Initial_Frame = 0
Final_Frame = 0
Subset_Start_Frame = 0
Subset_End_Frame = 0
Test_Abort = On
Test_Abort_Count = 100
--------------------------
>
> > // Mandelbulb - power 4 - Believe me the power 6 is a vision of hell!
>
> This teddy bear don't looks like real daemon, but some sort of inferno
> is present, no doubt ...

Have you ever seen Edvard Munk's painting 'The Scream'? It's disturbing but
Mandelbulb power 6 is worse.

Hope the ini settings will help.

Droj

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On 10/05/2024 01:04, Droj wrote:> Oh man you make me weep! 16 min with 
max_gradient=33566 ... if I try my image
> will be finished next week.
Hi, Droj.

Please, don't cry: I noticed, that your setting are too 'aggressive':
; Antialias_Depth = 9
; Antialias_Threshold = 0.0010
See: https://www.povray.org/documentation/view/3.6.1/223/

making less depth and threshold can seriously improve performance with
almost the same quality.

> Hope the ini settings will help.
Thanks for setting, you've saved a lot of time for me.

> Have you ever seen Edvard Munk's painting 'The Scream'?Yes, sure, this is a famous
painting, but I see something close to
Francisco Goya. :)

Happy poving,
--
YB

Post a reply to this message

Attachments:
Download 'fract_03_800x600.png' (95 KB)

Preview of image 'fract_03_800x600.png'

On 10/05/2024 01:04, Droj wrote:
>> Oh man you make me weep! 16 min with max_gradient=33566 ...

Hi, Droj.

Please, don't cry: I noticed, that your setting are too 'aggressive':
; Antialias_Depth = 9
; Antialias_Threshold = 0.0010
See: https://www.povray.org/documentation/view/3.6.1/223/

making less depth and threshold can seriously improve performance with
almost the same quality.

>> Hope the ini settings will help.

Thanks for setting, you've saved a lot of time for me.

>> Have you ever seen Edvard Munk's painting 'The Scream'?

Yes, sure, this is a famous painting, but I see something close to
Francisco Goya. 🙂

Happy poving,
-- 
YB

Post a reply to this message

Attachments:
Download 'fract_03_800x600.png' (95 KB)

Preview of image 'fract_03_800x600.png'