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Title: jcube formula question
Post by: jamesbradleym on January 20, 2017, 09:20:02 PM

Hello!

I'm working through Houdini and I've managed to get a semblance of the mandelbulb in 3d through use of it's 3d forumla - now I'm trying to determine what the fomula is for the JCube 3 set inside mandelbulb3d v 191.

I tried to find it through the .m3f file but all it says is

Code:

"[OPTIONS]
.Version = 4
.DEscale = 0.2
.DEoption = 2
.RStop = 1024
.DReci2 Alpha = .41421356
.Double Cx1 = 0
.Double Cy1 = 1
.Double Cz1 = 1
.Double Cx2 = 1
.Double Cy2 = 1
.Double Cz2 = 1
.Double GScale (test) = 3
[CODE]
558BEC535689C38B75088B7630B8FFFFFF7F2141042142042143049083C4B0DD
46B0D9E8D8E9D9C9D9E0DD5C2418DC46F0DD1424DC4EE8DD542408D9E8DEF1DD
542410DC4C2418D9E8DEC1DD5C241890DD01DD02DD03D8D1DFE0D0EC7202D9C9
D8D2DFE0D0EC7302D9CAD9C9D8D2DFE0D0EC7202D9CA90D9C0DD442410DED9DF
E0D0EC765290D9C0DC442418D9C2DED9DFE0D0EC764190DD46E0DCE9DDD8DD46
D8DCEADDD8DD46D0DCEBDDD8DD442408DCCBDCCADCC9DD4108DEC9DD5908DD46
E0DCC1DDD8DD46D8DCC2DDD8DD46D0DCC3DDD890EB3E90DD46C8DCE9DDD8DD46
C0DCEADDD8DD46B8DCEBDDD8DD042490DCCBDCCADCC9DD4108DEC9DD5908DD46
C8DCC1DDD8DD46C0DCC2DDD8DD46B8DCC3DDD89090DD1BDD1ADD1989D883C450
5E5B5DC20800
[END]

A brute-force IFS formula, that tries to replicate the "Jerusalem Cube" fractal.
It is discontinue, but it's the best known approximation of the formula.
Warning; GScale parameter may help to obtain more effects but discontinuities become more evident!"

Which is helpful to some extent but the formula isn't shown at all..

Anyone have any ideas on how to either parse the code and decompile it or maybe who know's the jcube formula used in v 191?

Thanks!

James[/code]

Title: Re: jcube formula question
Post by: DarkBeam on January 20, 2017, 09:31:43 PM

Formula is in the forums. No need to decompile! :)
I don't remember where but search for Jerusalem Cube
http://www.fractalforums.com/sierpinski-gasket/jerusalem-cube-can-be-made-via-kifs/

Title: Re: jcube formula question
Post by: jamesbradleym on January 20, 2017, 09:35:32 PM

Thanks so much!!

Title: Re: jcube formula question
Post by: DarkBeam on January 20, 2017, 09:48:51 PM

Formulas can be decompiled but it is very hard to interpret the results.
Sometimes it is even obscure to me
You are welcome :beer:
Luca

Title: Re: jcube formula question
Post by: jamesbradleym on January 20, 2017, 09:53:32 PM

Quote from: DarkBeam on January 20, 2017, 09:31:43 PM

Formula is in the forums. No need to decompile! :)
I don't remember where but search for Jerusalem Cube
http://www.fractalforums.com/sierpinski-gasket/jerusalem-cube-can-be-made-via-kifs/

So I just went through that link to the forums, I couldn't find an equation set that incorporated the 8 variables shown in the formulas tab (Alpha, Cx1, Cy1, Cz1, Cx2, Cy2, Cz2, GScale (test)).

Looking through each of the posts that searching Jerusalem cube pulls up..

Title: Re: jcube formula question
Post by: jamesbradleym on January 20, 2017, 10:27:25 PM

After closer inspection and a (attempted) reading of your discourse it may be that this:

Code:

JC4(x,y,z,alpha,beta){
   t=beta-1;
   scl=(alpha+t);
   scl1=scl/alpha;
   a=1/scl1;
   r=x*x+y*y+z*z;dd=1;
   for(i=0;i<MI && r<100;i++){
      x=abs(x);y=abs(y);z=abs(z);
      if(x<y){t=x;x=y;y=t;}
      if(z<x){t=z;z=x;x=t;}
      if(x<y){t=x;x=y;y=t;}

      if(y<a && x>1-beta*a+y){
         x-=1;z-=1;
         x*=scl1;y*=scl1;z*=scl1;dd*=scl1;
         x+=1;z+=1;
      }else{
         x-=1;y-=1;z-=1;
         x*=scl;y*=scl;z*=scl;dd*=scl;
         x+=1;y+=1;z+=1;
      }
      r=x*x+y*y+z*z;
   }
   (sqrt(r)-1.75)/dd
}

Is the jcube3 formula used inside mandelbulb3d v 1.91. However, I'm still uncertain as to which variables are Cx2, Cy2, Cz2, or Gscale. and for that matter I'm a bit stumped on Cx1, Cy1, and Cz1 - they aren't labeled as such in the actual code so I'm cautious to label them as x = Cx1 etc...

Title: Re: jcube formula question
Post by: DarkBeam on January 21, 2017, 08:39:25 PM

I no longer remember.
Cx,Cy,Cz should be some replacement to the x+=1 ... etc but ... do not remember much else!

Title: Re: jcube formula question
Post by: jamesbradleym on January 25, 2017, 08:13:53 PM

Ahh well, it's okay.. Still trying to figure it out but not having much luck just yet..

How do the multiple equation fractals work? I have _y2 reciprocal as the first equation with jcube following - not sure how they relate to form the fractal though.

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Fractal Software => Mandelbulb 3d => Topic started by: jamesbradleym on January 20, 2017, 09:20:02 PM