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Edward Coffey wrote:
> The trouble with rendering it as a solid object is that you have no more
> information than the location of each point - other than simple
> proximity there is no way of knowing whether two points should be
> connected forming part of a surface, or whether there is a gap between
> them that should not be filled. In the end you either just plot so many
> points that it looks like a single surface, or use a guessing algorithm
> designed to form a surface from a collection of points.
i don't think you need a guessing algorithm. maybe you could simply keep
the last three points in memory and create a triangle for a mesh with
it. then find the next point and create a triangle that uses two points
from the last one and the new point. if i am wrong here, just tell me
why, i don't know much about attractors...
bye,
Marc
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> No they are not, which is interesting because they often look 3D.
> For further examples see
> http://astronomy.swin.edu.au/~pbourke/fractals/peterdejong/
> http://astronomy.swin.edu.au/~pbourke/fractals/clifford/
> http://astronomy.swin.edu.au/~pbourke/fractals/lyapunov/
Hi
As you are the one I got the idea from, how do you generate your attractors?
How much points, what program, memory usage, runtime...
Thanks a lot for your scc entry (which brought me to attractors), I really have
a lot of fun playing with these.
Manuel
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Marc Roth wrote:
...
> i don't think you need a guessing algorithm. maybe you could simply keep
> the last three points in memory and create a triangle for a mesh with
> it. then find the next point and create a triangle that uses two points
> from the last one and the new point. if i am wrong here, just tell me
> why, i don't know much about attractors...
These attractors are generated by starting at some initial point in
space, then applying a function to that point to generate the next
point, repeating for as many iterations as you care to plot. The really
interesting thing about them (well, for me at-least) is that though the
points end up forming complex and intricate surfaces in three
dimensions, they aren't generated in a nice progressive sequence from
one end of the surface to the other. Instead they appear in a chaotic
pattern, jumping in a seemingly random sequence from one place to the next.
Put simply, you can't use the order of generation to decide how to
approximate the surface because while for any given point, n, it is
possible that point n+1 is right next to it, it is just as likely to be
over the other side of the object.
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Edward Coffey wrote:
> Put simply, you can't use the order of generation to decide how to
> approximate the surface because while for any given point, n, it is
> possible that point n+1 is right next to it, it is just as likely to be
> over the other side of the object.
ah, i didn't know that. instead of a guessing-algorithm one could also
use several steps to create a surface:
1) create all points and store them in a file
2) create triangles from them by taking one point and finding the 2
closest point
step two would be very cpu-time-consuming, as far as i know, so it's not
a very efficient way.
ciao,
Marc
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pdb### [at] swin edu au news:pdb_NOSPAM-
26E623.17592116032004@news.povray.org
> http://astronomy.swin.edu.au/~pbourke/fractals/peterdejong/
> http://astronomy.swin.edu.au/~pbourke/fractals/clifford/
> http://astronomy.swin.edu.au/~pbourke/fractals/lyapunov/
Realy, realy, nice :)
--
http://www.raf256.com/3d/
Rafal Maj 'Raf256', home page - http://www.raf256.com/me/
Computer Graphics
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Just in case anyone is interested in a free online versions of a book
about "Strange Attractors":
http://sprott.physics.wisc.edu/sa.htm
"Strange Attractors: Creating Patterns in Chaos (ISBN 1-55851-298-5)"
by Julien C. Sprott
--
Tor Olav
http://subcube.com
http://subcube.net
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Hi,
I had a lot of fun during the last days, playing with strange attractors.
I have put some of the most interesting ones here:
http://home.arcor.de/mad_onion/attractors/
My Java program which generated these is available here:
http://madonion.homeip.net/attractors/
Have fun!
Manuel
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> > No they are not, which is interesting because they often look 3D.
> > For further examples see
> > http://astronomy.swin.edu.au/~pbourke/fractals/peterdejong/
> > http://astronomy.swin.edu.au/~pbourke/fractals/clifford/
> > http://astronomy.swin.edu.au/~pbourke/fractals/lyapunov/
> As you are the one I got the idea from, how do you generate your attractors?
> How much points, what program, memory usage, runtime...
Since these aren't 3D I simply draw points on an image plane with
my own custom software. To get the nice grey/misty look I render
to a very large image, say 4k square and then scale it down with
antialiasing. I render millions, billions, ..... points, there is
no penalty except time because I don't need to keep anything in
memory except the final image which "evolves".
> Thanks a lot for your scc entry (which brought me to attractors), I really
> have a lot of fun playing with these.
There is something about them.....too bad no one voting in the scc3
thought much of my entry. :-)
--
Paul Bourke
pdb_NOSPAMswin.edu.au
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Manuel Kasten wrote:
>>each time using the previous frame as a background image_map
>>for the current frame. The result looks nice.
>>
How did you do that? I know it's an animation topic, but I've been
trying to do that unsuccessfully for a while.
Please help.
Bill
>
>
>
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> "Strange Attractors: Creating Patterns in Chaos (ISBN 1-55851-298-5)"
> by Julien C. Sprott
Excellent Tor! I've started reading this at my job (in secret since I
shouldn't use the internet for personnal use!) and I found it extremely
interesting...
Actually, I decided to try to create a PHP script that will render one
of these Chaotic attractors and I will try to work toward a more fractal
attractor. Eventually, I guess it will be pretty easy to port this PHP
code to OpenGL and have an interactive animation of it. I could even
add a function that would output a povray code to render it...
Now, I haven't read much of the book, but I wonder if it's possible to
make nice looking strange att. in 3D? Then POV-Ray will come handy to
make nice stereographs of the object.
Thanks,
Simon
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