Logo by teamfresh - Contribute your own Logo!

END OF AN ERA, FRACTALFORUMS.COM IS CONTINUED ON FRACTALFORUMS.ORG

it was a great time but no longer maintainable by c.Kleinhuis contact him for any data retrieval,
thanks and see you perhaps in 10 years again

this forum will stay online for reference
News: Follow us on Twitter
 
*
Welcome, Guest. Please login or register. March 28, 2024, 08:01:24 PM


Login with username, password and session length


The All New FractalForums is now in Public Beta Testing! Visit FractalForums.org and check it out!


Pages: 1 ... 3 4 [5] 6   Go Down
  Print  
Share this topic on DiggShare this topic on FacebookShare this topic on GoogleShare this topic on RedditShare this topic on StumbleUponShare this topic on Twitter
Author Topic: Amazing fractal  (Read 82946 times)
0 Members and 1 Guest are viewing this topic.
Jesse
Download Section
Fractal Schemer
*
Posts: 1013


« Reply #60 on: February 08, 2010, 09:34:50 PM »

In that case how are you calculating the DE ?
My formula has 2 methods available - two versions of my own smoothed iterations method and a version of Buddhi's method using:

                  dist = scalefix*deltamin*magn1*log(magn1)/abs(magn1-magn)

Where magn1 and magn are the magnitudes at step and step+deltamin.
This method essentially gives the same results as the smoothed iterations method.

Hmm, actually i am using also a method from Buddhi (thanks for that), using the 4 point method.
I think this method just lowers the probability to get under the stop-threshold in that unsteady regions, a lower accuracy may have done the rest.

A solution would be to change the calculation of magn to get smooth values again.
Tglad had choosen his formula carefully to this "unsteadyness problem", i guess.
So if we use one of the "bad math" formulas, we must take care of the folding and change Rold according to this special folding  huh?

But there is still so much to discover in the working formula, dont know if this so urgent.
Logged
Tglad
Fractal Molossus
**
Posts: 703


WWW
« Reply #61 on: February 09, 2010, 12:43:31 AM »

Yes, I would say that there are a lot of variations that don't tear space (have a step change), like rotating the space or offsetting it... and I suppose they are more steady.
David, thanks for info on getting close to objects, if you're using ultra fractal here are the tricks:

Set camera distance to small, like 1e-6. Place the camera by directly setting the target coords x,y,z. Note box's radius is about 6
Set the image plane distance to 0.05 and the front clip to a slightly smaller but negative number: -0.049, set the back clip to 10.
In the location tab set the centre to 0,0 and magnification to 40, and keep them fixed (this means _don't_ use ctrl+mouse drag or shift+mouse drag on the view)
Rotate the camera using the camera dir which is yaw clockwise, pitch upwards in degrees.
Leave dolly scale at 3.


Also I noticed that the occasional burnt/black areas in images are due to the ambient occlusion which you can turn off, not sure if that's a bug or just bad settings when I use it.
Logged
David Makin
Global Moderator
Fractal Senior
******
Posts: 2286



Makin' Magic Fractals
WWW
« Reply #62 on: February 09, 2010, 04:25:52 AM »

Also I noticed that the occasional burnt/black areas in images are due to the ambient occlusion which you can turn off, not sure if that's a bug or just bad settings when I use it.


The ambient occlusion method simply doesn't seem to work on the Mandelbox sad So it's definitely best to turn it off - and probably reduce the base ambient value from the default too.
Logged

The meaning and purpose of life is to give life purpose and meaning.

http://www.fractalgallery.co.uk/
"Makin' Magic Music" on Jango
David Makin
Global Moderator
Fractal Senior
******
Posts: 2286



Makin' Magic Fractals
WWW
« Reply #63 on: February 09, 2010, 04:40:49 AM »

Hmm, actually i am using also a method from Buddhi (thanks for that), using the 4 point method.
I think this method just lowers the probability to get under the stop-threshold in that unsteady regions, a lower accuracy may have done the rest.

A solution would be to change the calculation of magn to get smooth values again.
Tglad had choosen his formula carefully to this "unsteadyness problem", i guess.
So if we use one of the "bad math" formulas, we must take care of the folding and change Rold according to this special folding  huh?

But there is still so much to discover in the working formula, dont know if this so urgent.

Yes using Buddhi's full 4-point method would probably explain how your algorithm avoids the problem.
I just tried adding "soilid only if iteration count > minimum value" *and* de<threshold - this seemed to fix the problem though I still have some issues to sort out - in particular I'm having a problem tracing to get the shadows.

Also I decided that I'd try an extra stepping method to get solid at maxiter based on single point smooth iteration values using:

  Iteration distance estimate = @scale*(atan(1.0/smoothiteration) - atan(1.0/#maxiter))^@fudge

For normal z^p+c formulas the correct value of @fudge appears to be approx. 1+3*log2(p).

Logged

The meaning and purpose of life is to give life purpose and meaning.

http://www.fractalgallery.co.uk/
"Makin' Magic Music" on Jango
Jesse
Download Section
Fractal Schemer
*
Posts: 1013


« Reply #64 on: February 09, 2010, 10:37:16 AM »

Also I decided that I'd try an extra stepping method to get solid at maxiter based on single point smooth iteration values using:

  Iteration distance estimate = @scale*(atan(1.0/smoothiteration) - atan(1.0/#maxiter))^@fudge

For normal z^p+c formulas the correct value of @fudge appears to be approx. 1+3*log2(p).

I still have to try out all the different DE methods, but one idea that i used with steps in smoothed Iterations:

For example, when using the delta DE method and the estimated step is lower than StopThreshold, then calculate again with negated delta and if this value is much bigger you are on a step and have to use the bigger value.
Logged
David Makin
Global Moderator
Fractal Senior
******
Posts: 2286



Makin' Magic Fractals
WWW
« Reply #65 on: February 09, 2010, 03:47:02 PM »

Also I decided that I'd try an extra stepping method to get solid at maxiter based on single point smooth iteration values using:

  Iteration distance estimate = @scale*(atan(1.0/smoothiteration) - atan(1.0/#maxiter))^@fudge

For normal z^p+c formulas the correct value of @fudge appears to be approx. 1+3*log2(p).

I still have to try out all the different DE methods, but one idea that i used with steps in smoothed Iterations:

For example, when using the delta DE method and the estimated step is lower than StopThreshold, then calculate again with negated delta and if this value is much bigger you are on a step and have to use the bigger value.

Very good idea ! Or check the DE value calculated from the values at step+delta and step+2*delta smiley
Logged

The meaning and purpose of life is to give life purpose and meaning.

http://www.fractalgallery.co.uk/
"Makin' Magic Music" on Jango
Jesse
Download Section
Fractal Schemer
*
Posts: 1013


« Reply #66 on: February 09, 2010, 09:02:27 PM »

Or simpler, if the steps are only on different non-smoothed iteration counts:
Check these for equality and step one delta forward if not.

I tried out your 1 point method but it was hard to find good values, fudge=1 gave some results on a testimage, but tiny changes of the stop threshold (because of FOV settings and depth) was leading to great changes in the DE.
Higher fudge values seems to behave somewhat better, but i had to multiply the DE by 100 (fudge=2) or even more.
Maybe i have done something wrong.

Before i used the 4 point method, i had also a 1 point method based on smoothed iteration and maximum iteration only, but i dunno had lost this piece of code  sad
Logged
Tglad
Fractal Molossus
**
Posts: 703


WWW
« Reply #67 on: February 10, 2010, 12:56:08 AM »

David (or anyone who knows) do you know how I could try out a new colouring scheme? The scheme I would like to try is below, I think it might give more precise colouring. I can't see quite how to add this into the UF code though. Thanks for any help!

; initialise before iterating
colourScale = 1
totalColour = black

; each iteration choose colour based on the choice of folds for that position
int numOutside = 0
if x>1 || x<-1
 numOutside = numOutside+1
endif
if y>1 || y<-1
 numOutside = numOutside+1
endif
if z>1 ||  z<-1
 numOutside = numOutside+1
endif
if numOutside==3
  colour = red
elseif numOutside==2
  colour = blue
elseif numOutside==1
  colour = green
else
  float lengthSqr = MagnitudeSquared()
  if lengthSqr < minRadiusSqr
    colour = yellow
  elseif lengthSqr < fixedRadiusSqr
    colour = brown
  else
    colour = purple
  endif
endif
; reduce the amount geometrically each iteration, so each point converges on an exact colour
colourScale = colourScale*0.5
; accumulate the colour so each iteration we mix in a small amount of the new colour
totalColour = totalColour + colourScale*colour
« Last Edit: February 10, 2010, 12:58:31 AM by Tglad » Logged
David Makin
Global Moderator
Fractal Senior
******
Posts: 2286



Makin' Magic Fractals
WWW
« Reply #68 on: February 12, 2010, 01:05:52 AM »

Hmm, actually i am using also a method from Buddhi (thanks for that), using the 4 point method.
I think this method just lowers the probability to get under the stop-threshold in that unsteady regions, a lower accuracy may have done the rest.

A solution would be to change the calculation of magn to get smooth values again.
Tglad had choosen his formula carefully to this "unsteadyness problem", i guess.
So if we use one of the "bad math" formulas, we must take care of the folding and change Rold according to this special folding  huh?

But there is still so much to discover in the working formula, dont know if this so urgent.

Yes using Buddhi's full 4-point method would probably explain how your algorithm avoids the problem.
I just tried adding "soilid only if iteration count > minimum value" *and* de<threshold - this seemed to fix the problem though I still have some issues to sort out - in particular I'm having a problem tracing to get the shadows.

Also I decided that I'd try an extra stepping method to get solid at maxiter based on single point smooth iteration values using:

  Iteration distance estimate = @scale*(atan(1.0/smoothiteration) - atan(1.0/#maxiter))^@fudge

For normal z^p+c formulas the correct value of @fudge appears to be approx. 1+3*log2(p).



Much better method for using single-point smooth iteration for the DE:

  Iteration distance estimate = @scale*(atan(1.0/log(1+smoothiteration)) - atan(1.0/log(1+#maxiter)))^@fudge

I haven't finished investigating the correct values for @scale and @fudge yet but using 4 for @fudge looks pretty good on z^2+c smiley

Logged

The meaning and purpose of life is to give life purpose and meaning.

http://www.fractalgallery.co.uk/
"Makin' Magic Music" on Jango
David Makin
Global Moderator
Fractal Senior
******
Posts: 2286



Makin' Magic Fractals
WWW
« Reply #69 on: February 12, 2010, 04:03:54 AM »

I just updated my wip 3D formula for Ultra Fractal to include the Mandelbox - see here:

http://www.fractalforums.com/mandelbulb-implementation/update-to-the-mmf-wip-formula-for-ultra-fractal/

The implimentation includes Jesse's suggested fix for when negation of the triplex is enabled when the spherical inversions are applied.

Here's an example from using such negation when the magnitude is less than the maximum radius but greater than the minimum:

"Architectural Breakdown"



If no image above then look here:

http://makinmagic.deviantart.com/art/Architectural-Breakdown-153629028

Two more using the default settings for the Mandelbox:

"The God in Moties' Eyes"



If no image above then look here:

http://makinmagic.deviantart.com/art/The-God-in-Moties-Eyes-153629972

"After the earthquake"



If no image above then look here:

http://makinmagic.deviantart.com/art/After-the-earthquake-153744734
Logged

The meaning and purpose of life is to give life purpose and meaning.

http://www.fractalgallery.co.uk/
"Makin' Magic Music" on Jango
David Makin
Global Moderator
Fractal Senior
******
Posts: 2286



Makin' Magic Fractals
WWW
« Reply #70 on: February 12, 2010, 04:36:41 AM »

David (or anyone who knows) do you know how I could try out a new colouring scheme? The scheme I would like to try is below, I think it might give more precise colouring. I can't see quite how to add this into the UF code though. Thanks for any help!


Nice idea - it's basically the same as a colouring method often implimented for escape-time IFS, I'll see if I can get it added in an update this weekend smiley
Logged

The meaning and purpose of life is to give life purpose and meaning.

http://www.fractalgallery.co.uk/
"Makin' Magic Music" on Jango
Timeroot
Fractal Fertilizer
*****
Posts: 362


The pwnge.


WWW
« Reply #71 on: February 12, 2010, 04:43:27 AM »

Could you by any chance give a upr? I'm getting loads of noise... more than I prefer...
Logged

Someday, man will understand primary theory; how every aspect of our universe has come about. Then we will describe all of physics, build a complete understanding of genetic engineering, catalog all planets, and find intelligent life. And then we'll just puzzle over fractals for eternity.
David Makin
Global Moderator
Fractal Senior
******
Posts: 2286



Makin' Magic Fractals
WWW
« Reply #72 on: February 12, 2010, 04:49:47 AM »

Could you by any chance give a upr? I'm getting loads of noise... more than I prefer...

Code:
MMF-AmongstTheAsteroids {
; Copyright © 2010 by David Makin.
::Tohqugn2Nm1SPuNOS47BI/HM0pZQSbLqXWeWwDJpzCMAJTyuJADweYDolos10Siaokb32/6n
  q4DJKZ3OtPxis4H/YxiVxSuQyy6ZV/2rf1iF9l9Vcq3n/8/exdLeXtoZXX/i+98FvrrnLFl5
  deLOWm3vnmE5vYPvc3+eaUq/iK2JusjSQQyk88y+Oq39sHLzX8Z2DlN/rgVkgVB+EfvX/Kly
  q1Lj12XKaoevnl9wOp4QTu3CRLLrs/El47vom3vXkTrPU1X2y66W0LZNdtMJvpnei396XVza
  bLb2phD6lLp+LJpphJp+xJpxruzfZQg/GYtDT3EvomtrhGsMej/a/okX/qChEQnpmfN7pSEA
  i/iWuMbPP7BqooYRRZFvhVrtMHLbDvvhfc5hiavFwKKPR9+zf/rh3H7hg0+jDd8eZ5OajAE6
  5dgVV3+RwGhbXySCI1tXcsspQo3H4ErFPCmuueQhowNxJxGtw9lkj6BdUoPv6P1C8J8ew+2k
  zr2KF9mlv4Q+OOAh/oyv/Q1W6fuH2cr+jTV4EkGd1jHeP17TijcLYin8gBbrO0pJusFOPRO/
  EYiQo1zGlIgx0X1usheHZoNhenegTmpYaq0XP9TOT5k7UOPOlzOLxZr+6pf2dKbbPKpBoNss
  B9AQTHMVpBmG+uu29cwI2I0zeoHieL2lxAX/7CHNKRgR5/cgBOENwh2iz//g3kZMxdiqyc69
  fc1vDjyQXY8kWyaN+refVU20jOrtemROLLp+rMUX1xf9A2BIJkbL7VOeJaWraH5r2XsyKxBw
  jwPIyux76ZyeNcWpBs0SgBAFyENdoiwVA/4V+LT1zX1NMD8mxKHNxphHytgnAYMV4Vj21UlO
  5lg/L4ZFM4lf/Hpe/vFPyqOw780dFHQM+psssDgh8ENSfqods53Fa81LbUbTfdbt5XfYpazq
  qsAdoXgTub4sD1vn3SJf8uYjInB3Xpxf8O0ECuw9MaM/OcpVXjV3AtTurjnbwGY8WwpaQAgq
  o8JtHB0QDkSCGEJy4l1/+QZ2DNQ0DWVnjLkuHzOBpNL/vOg7c9Rrm32TSJvoin1PGpYwJ1Ib
  iGEgbEwvoD8JPjNb2Vxh2+2DUhMHFVaxRt8e6tne753eEPWKbQPI7uY7D7GsFQ7sKwVLYdKZ
  jvfKCQ/TnQ3HjjR/5jWnJWtmN4OJXUVdiGa3HZQ0H4moPEhX5dDSjQAxqh4N0vCB/ahNL4Fh
  cCsC411isKopBmtKhAsfsl5mpqZhUAR8131VdsFyY4IHMsnUSV8CXtDkqMVjdEOCd42+6xYS
  qe6FtuLlKU772CX6P0ztdiWpVDqcG3vjIQUWgxhFySMh1YPRjrf0E4HxIayKEd2eMgCThPSy
  yLhQ1T2EZiawzGAuJX5hARRkQeSIOPaKgWLezihoXeqJJH3E4VT9VS/lbI4lsKlTG9kCs6Ww
  B7NFwy8Ld/ts/XOBxGh4j/6vqiPW8jzFN0ycYLbuDUJyofSkZjUmdofkQFvv2kL691Uv66il
  QyqfDS0+j3V1D95pHa5j/YHvhLLzUPMw2HoPkLsYb94lKcgaROkd8+yHXQSsA0xhr9kgwo4E
  TPSdSNsJGzH2rr9XTcQhVCp9bHUiBBAZQEw/QdH30Zp6NHfCs1Mppr8yMO1Bn8D11no+DcT2
  u3EiBE5PNuA7Y11sBPZlyQeGd2MUqScEjeYF3DHlwlnlJD/WPOzK+jcIyUqd3DvjAerU34CX
  Ux25bfUhxE4fhNQ25Pu/rbdEagZ77gFZM2oFOiBuBsIuYRcxCSyDvKzZ6AiBzYXwc4CchLw1
  kDICyQkzYH8CnhX4c8CnARNEmwhhh0wwlrdxLaGeRXx6F5SxIX8AhklpTAM+STY8cOG7CYsL
  gx0wNLDXPzImMjkJzBMxFwkZGxEaQ6SyEr46ZAueOgrnZFX7Sy104lJTwLdGepXxKmqebnBv
  UnbEAipUymlJTNkbu0QuZON34i5mpYuhGmsMG45UbJZ+9Fi/Fe4+uwqGPeiFF6KFee/E6SIz
  x9ybOEa0ErqSlAHODdEEvMc6hFJ4K3Kv4eE0TkDyBKknya42E8A0pnck5XoIhX5sD6M1BcUF
  yEeDXsgsMzsIRXh3RXwb8OkD2oC+JzpeEkZMdmZJeOzjvGzhbUuHmoO+hTJfM86JoeTF5x8a
  uZRBZn0mVmEv0PAlSKZv5LQh1y38t9scxxO74QGGT6Fbq8uhE/PaaVI2B60w1N1ZSBWsJaTy
  6gNx6ux0RQ2uhkiidFYHrtIoT1ofmaLUkrx/XVLiiJuv2W3xQVVaR9cZ1bhBC1tkGGCN3NaG
  AptjDUZamXCLq5B/w7CNNrU1xNMVUkgJ81F5VhP6z8yJMxsqZl9hKI7Ge1i5yyuBZc+uCw7Z
  17j/LvWofXHAJW3GdoSLoHoAKD0aBbFlapdTk26IhbJ4WkpYzD61S/eDVTy46+YZX52KOxYY
  qI4aO8cGlodVVC7cF2OIg1eS/SRRHvXJrf/oFkzQttGFxXPGFvKULBk1cXoqbPxiGSxADF1Q
  YYZgllBGWabPRYnrwWnNTwMWGM8K3qgRKGYoYiWyQRDEd7DcZZ4FGyQLFDdoYoliGUCdZZor
  hMcGFDHpYomiWImwywJGyQXKGdBFjGvdUF5wyIXDZkLFjcpYkDFtoMyyoRDZ0EKGNhiROWDk
  lxXwyYrhM2hixuUM2SRDOxusMemhMekixjUMegiWMmwyYXDZyFUMxSxkpXaScZZirhMxliJz
  oYykLNJjsMZihMZCFT0rbZTHUzj+7oiflyCIUeDEm+1vCK/eYIoqoO1X3EzdPoXlYnzXZEKq
  Ja5hsKV1UmvwIUQU027sFvdfpEKl2z9bKOUlnoBKNfI4t+DSNUxiu6fr90WNgw052SWnNGmo
  ypkqmMaltCnrH4+QhJR0Qd4jlc+teWTOTmrqszK8jvgpa+uEqJxb2MuoWP3Rw2KYhhuy8wah
  BT2t0Sb1BLC1DKltW0o4FykvbHx7ZnzUudL1GXmfiiH64yXsy4nO8Fqs+7Ma/o4rehaifE6u
  LPFvQ7cZZR/LBWzn27npGcBT99Bo+vUNVfLtf+y/A/4LTrXGeM1Xx6y9T3eG+F5vuvO6c9NU
  B1HG27qz9Ge92xVMVtOE/nxgCH1X3rmL9euZ8S8pVaNsE/U1afRqCP9UyZ55Eq/NU4mOQOoE
  Qv1KVcoJT5fpDkdL0E4Xt9mkC04FwKNOBPPOstX7mm+jX98OSfGG/DViOe3leS4cvhjkZY1f
  VBuKX5wZmKHL733vHOE2Lqyv6h5wgmyRHHCCsp/nSucPOEf+G7zPY05e8ro3kx9eOQut/rjW
  qoc3IzwgqqD33f67D7NcHYztoyj3VLEwTHwHBU2kzfiGGvQNdKJN20VyGTXxk4NkEb3b0/Np
  aljDijCC2YGiElaHIhQCDXHZRfzmhBWvedABqx18Hl6SHILuWf/h/G1gYQ1/BcoQ7aI=
}
Logged

The meaning and purpose of life is to give life purpose and meaning.

http://www.fractalgallery.co.uk/
"Makin' Magic Music" on Jango
David Makin
Global Moderator
Fractal Senior
******
Posts: 2286



Makin' Magic Fractals
WWW
« Reply #73 on: February 12, 2010, 04:51:23 AM »

Could you by any chance give a upr? I'm getting loads of noise... more than I prefer...

I should have added that when using the "negation" options on the Mandelbox then you should usually enable "Double check for solid" in the Render settings section.
Logged

The meaning and purpose of life is to give life purpose and meaning.

http://www.fractalgallery.co.uk/
"Makin' Magic Music" on Jango
David Makin
Global Moderator
Fractal Senior
******
Posts: 2286



Makin' Magic Fractals
WWW
« Reply #74 on: February 12, 2010, 09:55:59 PM »

For anyone having problems getting a decent render of the default Mandelbox using my UF formula - you should note that the default Mandelbox is approximately a cube centred at the origin with sides of length around 12 units i.e. it is considerably larger than the default viewing settings are set for.
So from the default to view the Mandelbox change the "Camera distance" to 11 and the "Back clip" to 23 and you will get a better view.
Also because of the difference in scale to the Mandelbulbs, change the "Solid Threshold" to say 1e-2 instead of 1e-3.
Logged

The meaning and purpose of life is to give life purpose and meaning.

http://www.fractalgallery.co.uk/
"Makin' Magic Music" on Jango
Pages: 1 ... 3 4 [5] 6   Go Down
  Print  
 
Jump to:  

Related Topics
Subject Started by Replies Views Last post
My Amazing Fractal! Mandelbulb 3d Weber 3 3788 Last post March 15, 2012, 01:03:06 AM
by Weber
Amazing fractal bulb - 3D print Mandelbulb3D Gallery bib 2 2355 Last post March 06, 2013, 07:49:07 AM
by jehovajah
Amazing Fuid Sea Creature, Fractal for sure Fluid Dynamics, Turbulence & Weather Prediction LMarkoya 4 5250 Last post March 28, 2015, 09:44:31 PM
by Cyclops
Fractal Death Valley - An Amazing Box Platinum landscape Movies Showcase (Rate My Movie) schizo 4 4831 Last post January 13, 2014, 09:12:15 PM
by schizo
Amazing discovery...Fractal DNA Images Showcase (Rate My Fractal) thom 0 1571 Last post March 23, 2016, 01:22:04 AM
by thom

Powered by MySQL Powered by PHP Powered by SMF 1.1.21 | SMF © 2015, Simple Machines

Valid XHTML 1.0! Valid CSS! Dilber MC Theme by HarzeM
Page created in 0.551 seconds with 25 queries. (Pretty URLs adds 0.011s, 2q)