what is interfering with what?
It has been said many times already; the circular pattern is interfering with the pixel sampling grid. At the center of the ball, the frequency of the circular patterns are low and do not alias when you sample it at the discrete pixel locations. At the higher frequencies, the circular patterns do alias becuase you cannot capture the high frequency details with the low sampling frequency. That is where the interference patterns are coming from.
what is interfering with what?
It has been said many times already; the circular pattern is interfering with the pixel sampling grid. At the center of the ball, the frequency of the circular patterns are low and do not alias when you sample it at the discrete pixel locations. At the higher frequencies, the circular patterns do alias becuase you cannot capture the high frequency details with the low sampling frequency. That is where the interference patterns are coming from.
this is not dependant at grid resolution if you will have many times larger grid of pixels you will see a wide waves of color, grid is not more important for visualisation here as with normal bitmap thing - it does not produce the effect only downsamples it - so i still not see where is interference here i do not see it, the image isa an effect of colouring not
intefrerention (image as i said is 'downsampled' but this is the same like when for example mandelbrot set visualization or raytracing images visualisation)
I am impressed with the patience shown here. It's a Moire pattern.
I am impressed with the patience shown here. It's a Moire pattern.
For me it seem s that moire is some broad class of visuals, and this one kind is some specyfic type of fractal - maybe deserves its own name (i dont know, im not sure). For me it is interesting object maybe i will do a little explorer of it later..
See:
On any of those pictures:
Since the TV that I use with my computer has a resolution that doesn't quite match up with the natural resolution of the graphic card, I get Moire patterns exactly like yours when I have zoomed completely out. When I zoom in, the pattern disappear. The pictures are static. (CTRL + mouse scroll on Mac to zoom, or what you have configured. Not sure how to activate on Windows any more.)
You will probably not see the same result, unless you pick a resolution that does not quite match up with the resolution on the screen, but the reason is the same: ALIASING. Aliasing makes Moire patterns.
Aliasing happens when you show high frequency data on a low(er) frequency medium.
Have a look here: http://www.svi.nl/AliasingArtifacts
Even TV / video producers avoid having certain clothes to avoid aliasing effects. You don't often see clothes with high contrast horizontal stripes, for instance: http://www.assetmediagroup.com/what-to-wear-for-video-shoot.html
i dont know how to count a dimension do you know how to count this based on that picture?
Fractals are not pretty pictures: They are subsets of R^n with certain self-similarity properties. So you have to start by defining a subset of R^n in some way. A picture doesn't help much.
See:
On any of those pictures:
Since the TV that I use with my computer has a resolution that doesn't quite match up with the natural resolution of the graphic card, I get Moire patterns exactly like yours when I have zoomed completely out. When I zoom in, the pattern disappear. The pictures are static. (CTRL + mouse scroll on Mac to zoom, or what you have configured. Not sure how to activate on Windows any more.)
You will probably not see the same result, unless you pick a resolution that does not quite match up with the resolution on the screen, but the reason is the same: ALIASING. Aliasing makes Moire patterns.
Aliasing happens when you show high frequency data on a low(er) frequency medium.
Have a look here: http://www.svi.nl/AliasingArtifacts
Even TV / video producers avoid having certain clothes to avoid aliasing effects. You don't often see clothes with high contrast horizontal stripes, for instance: http://www.assetmediagroup.com/what-to-wear-for-video-shoot.html
so, explain me - you think that underlaying image is something 'less
fractal' and only presenting it on the pixelgrid makes it looking fractal-like?
I do not see the reason to belive that underlying image is something much simpler that the thing you see on the grid (for hihg frequenzy palette I think it is more complex than the thing you see)
so if this is not true i do not get why to force me to belive in this.;\
I am going to give it another try:
And lastly similar to your effect:
Unfortunately it is poor quality, but you get the point.
I am going to give it another try:
Unfortunately it is poor quality, but you get the point.
the last didnt work, the third was interesting
what point? the difference of opinions was on the topics if
1) this is a fractal
2) if this is a result of an interference (related to 'presentation artifact')
above with such moire there was two drawings interfering, in my example algorithm i just calculate the pixel color with given not
complex function then set pixel and i just doubt (and tend to disagree)
if the resulting 'fractal pattern' comes from the discretization to grid values, imo it seems that underlying 'fluid' function has it implied
it may be related to some "inner" interferency of parts of its math formula
but probably is not related to screen presentation artifacts
but do not matter i doubt this is worth talking to much, i was interested
more if this specyfic ball fractal-like moire - like object has a specyfic name
(as to moire i was not denying that it may be somewhat related but i said that moire seem to be a whole family not the specyfic one, and maybe there is some specyfic name,
as to being a fractal i am not seeing if this is a worse object to
being fractal that for example
http://en.wikipedia.org/wiki/Sierpinski_carpet
which seem to be somewhat resemblin this ball i was talking about here)
As everyone suspected, it's just a Moiré pattern. Here's my attempt at producing it:
#include <cstdio>
#include <cmath>
int main() {
std::puts("# ImageMagick pixel enumeration: 800,800,255,srgb");
for (int j=0; j<800; ++j) {
double y = (400.0 - j) / 360.0;
for (int i=0; i<800; ++i) {
double x = (i - 400.0) / 360.0;
double z2 = 1.0 - x * x - y * y;
double distance = (z2 >= 0.0) ? std::sqrt(z2) : 0.0;
double color = std::fmod(1000.0*distance, 1.0);
int r = 256 * color;
int g = 256 * color;
int b = 256 * (1.0 - color);
r = r > 255 ? 255 : r < 0 ? 0 : r;
g = g > 255 ? 255 : g < 0 ? 0 : g;
b = b > 255 ? 255 : b < 0 ? 0 : b;
std::printf("%d,%d: (%d,%d,%d) #%02X%02X%02X srgb(%d,%d,%d)\n",
i, j,
r, g, b,
r, g, b,
r, g, b);
}
}
}
I compiled that code and then executed it, passing the output through `| convert TXT:- output.png' (`convert' is a command-line utility, part of ImageMagick). The output is this:
[EDIT: If you replace 1000.0 with something like 250.0, you'll get an image much closer to the original in this thread.]
