6 ms·

Making a 4K Fractal Movie with Fractal EXtreme

78 points by dmit 11y ago

tetraodonpuffer 11y ago
Like many others here I am sure, I was quite obsessed with fractals way back, fractint was awesome, and I did spend quite some time writing an integer math fractal generator in assembly on my AtariST back then (I remember enjoying just how many registers I could use on M68k compared to my friends that were working with x86 and how it made things so much simpler, I really enjoyed M68k assembly) When I first found XaoS in later years it was amazing, thinking that you could actually zoom in real time (!) and it's nice to see that some programs are still around allowing you to do fractals. It would be interesting to know which would be the fastest way to calculate them nowadays, if on the CPU or on the GPU (I think in both cases one would have to roll their own high precision math for deep zooms) (edit) found a post on the Fractal Extreme blog discussing GPU math, it is from 2012 though, I wonder if the intervening 4 years have changed the author's opinion on this. https://randomascii.wordpress.com/2012/03/28/fractal-and-crypto-performance/ https://randomascii.wordpress.com/2012/03/28/fractal-and-cry...
- RamshackleJ 11y ago
  I think it is no question that GPU's handle fractal renders significantly better than the CPU does. If you are rendering a fractal properly each pixel can be computed separately from all others, a problem that is perfect for the massive parallel multiprocessor. I would even go far to say that with current GPU hardware rendering fractals is "solved" in terms of realtime capability. see: https://www.shadertoy.com/results?query=fractal https://www.shadertoy.com/results?query=fractal I think fractals are still awesome despite being pretty simple these days. They are an excellent gateway into doing programing on the GPU. I think they are exactly the type awe inspiring programs that younger students should be shown.
  - deleted 11y ago
    [deleted]
  - ghusbands 11y ago
    A lack of arbitrary precision makes GPUs unsuitable for deeper Mandelbrot zoom levels, so "solved" is overstating it.
    - RamshackleJ 11y ago
      how many levels are you talking about? I agree the worse floating point precision of GPUs puts them at a disadvantage but they still do better for massively parallel problems like fractal renders. (http://www.bealto.com/mp-mandelbrot_benchmarks.html http://www.bealto.com/mp-mandelbrot_benchmarks.html)
      - ctdonath 11y ago
        The more interesting zooms magnify something like 10^256 times.
      - brucedawson 11y ago
        GPUs are happiest when doing float precision, which is 24 bits. Most GPUs can, at reduced speed, do double precision, which is 53 bits. The maximum precision for this zoom movie is 960 bits. So, unless you write code to compose high-precision math operations out of double-precision math then the GPU cannot even participate. And once you do that you will find that the GPU's speed advantage is mostly or entirely lost.
        Houshalter 11y ago
        CPUs can't do 960 bit operations either.
        rincebrain 11y ago
        Yes, but we have a lot more experience and existing code for solving this on more monolithic systems, whereas the massively parallel architecture of a GPU stops having so many advantages when you have heavy dependencies between operations on different "cores" (e.g. needing to compose arbitrary-precision math out of smaller operations), and thereby end up needing to synchronize rather than letting the threads compute in parallel.
ytdht 11y ago
If you plan to watch most of your movies in 4K, you probably should wait about 10 years before buying a new TV... the movie industry doesn't adapt very quickly and cable compresses everything so much that you can't even get true 1080 even if they say that they have HD
- ploxiln 11y ago
  Really, for video, 1080p is absolutely fine, if the video is not over-compressed. Even around 20mbps, 4k won't look better than 1080p, for full-motion full-color video content. Typical movie theaters use 4k today, and 2k (very close to 1080p) less than 10 years ago. For their huge screens. Of course the bitrate is very high, "up to 250 Mbit/s" (https://en.wikipedia.org/wiki/Digital_cinema#Technology_and_standards https://en.wikipedia.org/wiki/Digital_cinema#Technology_and_...) For small text and fine lines such as used in a close-up computer monitor, 4k+ can be very beneficial. But for video, it's marketing, and a costly waste.
  - ytdht 11y ago
    One good example is that most Blu-ray movie discs are just DVDs converted to take more space (quality was not increased)
    - arthurfm 11y ago
      I have rented lots of Blu-rays and never found one that was upscaled from DVD to 1080p. Can you provide more details please since I am having a hard time believing that's true.
      - ytdht 11y ago
        I did a quick Google search and found this article [1] ... I recall seeing a website that was listing Blu-ray titles with true-1080p but I can't find it right now. Cable does something similar by highly compressing HD content. 1. http://conversation.which.co.uk/technology/many-blu-rays-no-better-than-upscaled-dvds/ http://conversation.which.co.uk/technology/many-blu-rays-no-...
Animats 11y ago
Fractals in the browser, in WebGL, in real time.[1] Pan and zoom around. Much fun. [1] http://hirnsohle.de/test/fractalLab/ http://hirnsohle.de/test/fractalLab/
- exodust 11y ago
  Absolutely. And it's not obvious, but you can move around with WSAD keys, and QE for up/down. It would be nice to make rendered animations in this, I don't think that's a feature of the web app. Maybe there's some other way to make animations? Would make a great background for an alien ship flying through an alien cityscape.
Houshalter 11y ago
What's with the all the software and even file formats not supporting 4K? I mean yes it's a very uncommon resolution, but why have the number of possible resolutions fixed at all?
- brucedawson 11y ago
  An excellent question. I was surprised to realized that all three video editing programs had hard-coded limits. Odd.
pdkl95 11y ago
If you like this kind of zoom into the Mandelbrot set, check out this[1] zoom to 2^1116 from a few years ago (which is also available in 4k). The final ~2/5 of the zoom is probably the trippiest part of the Mandelbrot set I've ever seen, with a repeating "evil eye (nazar)"/"eye of sauron" motif[2] of incredible complexity. [1] https://www.youtube.com/watch?v=PbwaFQ2r2c4 https://www.youtube.com/watch?v=PbwaFQ2r2c4 [2] http://imgur.com/a/cwVHZ http://imgur.com/a/cwVHZ
- brucedawson 11y ago
  Very nice. Thanks for sharing.
kristiandupont 11y ago
It's funny, I always found fractal zooms to be deeply unsatisfying. Although I know it won't happen, I keep waiting for some kind of resolution or goal. In a philosophical way, I think I have a bit of the same feeling towards life itself.. :-)
- inDigiNeous 11y ago
  Yeah I always get the same feeling too. Traditional mandelbrot/julia whatever fractals are nice, but really boring IMO.
pantalaimon 11y ago
Ever since I've discovered 3D fractals, 2D ones simply don't cut it for me anymore. Unfortunately they are much harder to calculate. http://blog.hvidtfeldts.net/index.php/category/mandelbulb/ http://blog.hvidtfeldts.net/index.php/category/mandelbulb/

78 points by dmit 11y ago

Like many others here I am sure, I was quite obsessed with fractals way back, fractint was awesome, and I did spend quite some time writing an integer math fractal generator in assembly on my AtariST back then (I remember enjoying just how many registers I could use on M68k compared to my friends that were working with x86 and how it made things so much simpler, I really enjoyed M68k assembly) When I first found XaoS in later years it was amazing, thinking that you could actually zoom in real time (!) and it's nice to see that some programs are still around allowing you to do fractals. It would be interesting to know which would be the fastest way to calculate them nowadays, if on the CPU or on the GPU (I think in both cases one would have to roll their own high precision math for deep zooms) (edit) found a post on the Fractal Extreme blog discussing GPU math, it is from 2012 though, I wonder if the intervening 4 years have changed the author's opinion on this. https://randomascii.wordpress.com/2012/03/28/fractal-and-crypto-performance/ https://randomascii.wordpress.com/2012/03/28/fractal-and-cry...

RamshackleJ 11y ago
I think it is no question that GPU's handle fractal renders significantly better than the CPU does. If you are rendering a fractal properly each pixel can be computed separately from all others, a problem that is perfect for the massive parallel multiprocessor. I would even go far to say that with current GPU hardware rendering fractals is "solved" in terms of realtime capability. see: https://www.shadertoy.com/results?query=fractal https://www.shadertoy.com/results?query=fractal I think fractals are still awesome despite being pretty simple these days. They are an excellent gateway into doing programing on the GPU. I think they are exactly the type awe inspiring programs that younger students should be shown.
- deleted 11y ago
  [deleted]
- ghusbands 11y ago
  A lack of arbitrary precision makes GPUs unsuitable for deeper Mandelbrot zoom levels, so "solved" is overstating it.
  - RamshackleJ 11y ago
    how many levels are you talking about? I agree the worse floating point precision of GPUs puts them at a disadvantage but they still do better for massively parallel problems like fractal renders. (http://www.bealto.com/mp-mandelbrot_benchmarks.html http://www.bealto.com/mp-mandelbrot_benchmarks.html)
    - ctdonath 11y ago
      The more interesting zooms magnify something like 10^256 times.
    - brucedawson 11y ago
      GPUs are happiest when doing float precision, which is 24 bits. Most GPUs can, at reduced speed, do double precision, which is 53 bits. The maximum precision for this zoom movie is 960 bits. So, unless you write code to compose high-precision math operations out of double-precision math then the GPU cannot even participate. And once you do that you will find that the GPU's speed advantage is mostly or entirely lost.
      - Houshalter 11y ago
        CPUs can't do 960 bit operations either.
        rincebrain 11y ago
        Yes, but we have a lot more experience and existing code for solving this on more monolithic systems, whereas the massively parallel architecture of a GPU stops having so many advantages when you have heavy dependencies between operations on different "cores" (e.g. needing to compose arbitrary-precision math out of smaller operations), and thereby end up needing to synchronize rather than letting the threads compute in parallel.

ytdht 11y ago

If you plan to watch most of your movies in 4K, you probably should wait about 10 years before buying a new TV... the movie industry doesn't adapt very quickly and cable compresses everything so much that you can't even get true 1080 even if they say that they have HD

ploxiln 11y ago
Really, for video, 1080p is absolutely fine, if the video is not over-compressed. Even around 20mbps, 4k won't look better than 1080p, for full-motion full-color video content. Typical movie theaters use 4k today, and 2k (very close to 1080p) less than 10 years ago. For their huge screens. Of course the bitrate is very high, "up to 250 Mbit/s" (https://en.wikipedia.org/wiki/Digital_cinema#Technology_and_standards https://en.wikipedia.org/wiki/Digital_cinema#Technology_and_...) For small text and fine lines such as used in a close-up computer monitor, 4k+ can be very beneficial. But for video, it's marketing, and a costly waste.
- ytdht 11y ago
  One good example is that most Blu-ray movie discs are just DVDs converted to take more space (quality was not increased)
  - arthurfm 11y ago
    I have rented lots of Blu-rays and never found one that was upscaled from DVD to 1080p. Can you provide more details please since I am having a hard time believing that's true.
    - ytdht 11y ago
      I did a quick Google search and found this article [1] ... I recall seeing a website that was listing Blu-ray titles with true-1080p but I can't find it right now. Cable does something similar by highly compressing HD content. 1. http://conversation.which.co.uk/technology/many-blu-rays-no-better-than-upscaled-dvds/ http://conversation.which.co.uk/technology/many-blu-rays-no-...

Animats 11y ago

Fractals in the browser, in WebGL, in real time.[1] Pan and zoom around. Much fun. [1] http://hirnsohle.de/test/fractalLab/ http://hirnsohle.de/test/fractalLab/

exodust 11y ago
Absolutely. And it's not obvious, but you can move around with WSAD keys, and QE for up/down. It would be nice to make rendered animations in this, I don't think that's a feature of the web app. Maybe there's some other way to make animations? Would make a great background for an alien ship flying through an alien cityscape.

Houshalter 11y ago

What's with the all the software and even file formats not supporting 4K? I mean yes it's a very uncommon resolution, but why have the number of possible resolutions fixed at all?

brucedawson 11y ago
An excellent question. I was surprised to realized that all three video editing programs had hard-coded limits. Odd.

pdkl95 11y ago

If you like this kind of zoom into the Mandelbrot set, check out this[1] zoom to 2^1116 from a few years ago (which is also available in 4k). The final ~2/5 of the zoom is probably the trippiest part of the Mandelbrot set I've ever seen, with a repeating "evil eye (nazar)"/"eye of sauron" motif[2] of incredible complexity. [1] https://www.youtube.com/watch?v=PbwaFQ2r2c4 https://www.youtube.com/watch?v=PbwaFQ2r2c4 [2] http://imgur.com/a/cwVHZ http://imgur.com/a/cwVHZ

brucedawson 11y ago
Very nice. Thanks for sharing.

kristiandupont 11y ago

It's funny, I always found fractal zooms to be deeply unsatisfying. Although I know it won't happen, I keep waiting for some kind of resolution or goal. In a philosophical way, I think I have a bit of the same feeling towards life itself.. :-)

inDigiNeous 11y ago
Yeah I always get the same feeling too. Traditional mandelbrot/julia whatever fractals are nice, but really boring IMO.

pantalaimon 11y ago

Ever since I've discovered 3D fractals, 2D ones simply don't cut it for me anymore. Unfortunately they are much harder to calculate. http://blog.hvidtfeldts.net/index.php/category/mandelbulb/ http://blog.hvidtfeldts.net/index.php/category/mandelbulb/