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8 Jul 2024 08:37:41 EDT (-0400)
  Fractal screen (Message 11 to 20 of 20)  
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From: Anthony D  Baye
Subject: Re: Fractal screen
Date: 8 Aug 2015 19:40:02
Message: <web.55c69275771bab4d2aaea5cb0@news.povray.org>
"Samuel Benge" <stb### [at] hotmailcom> wrote:
> "Samuel Benge" <stb### [at] hotmailcom> wrote:
> > Maybe I'll get something going and upload it to glslsandbox.
>
> OK, here's something if anyone's interested: http://glslsandbox.com/e#27058.0
>
> You'll have to place the mouse in the lower left corner to properly initialize
> the layers (goofy mistake). Seeds are automatically placed under the mouse
> cursor.
>
> The effect tends to be large-scale compared with other diffusion-limited
> aggregation setups, but it can be tweaked by changing the settings.

neat. But is there a way to add constructive interference?  It could make a
great simulator for frost, if you could do that.

Regards,
A.D.B.


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From: Samuel Benge
Subject: Re: Fractal screen
Date: 8 Aug 2015 20:35:01
Message: <web.55c6a002771bab4db426f96a0@news.povray.org>
"Anthony D. Baye" <Sha### [at] spamnomorehotmailcom> wrote:
> "Samuel Benge" <stb### [at] hotmailcom> wrote:
> > "Samuel Benge" <stb### [at] hotmailcom> wrote:
> > > Maybe I'll get something going and upload it to glslsandbox.
> >
> > OK, here's something if anyone's interested: http://glslsandbox.com/e#27058.0
> >
> > You'll have to place the mouse in the lower left corner to properly initialize
> > the layers (goofy mistake). Seeds are automatically placed under the mouse
> > cursor.
> >
> > The effect tends to be large-scale compared with other diffusion-limited
> > aggregation setups, but it can be tweaked by changing the settings.
>
> neat. But is there a way to add constructive interference?  It could make a
> great simulator for frost, if you could do that.

I was thinking about another version that adds a water tank/ripples effect to
the solution... is that what you mean? It would be interesting to see how the
solid layer builds faster in areas of the solution where it's concentrated due
to CI. Hm...


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From: Anthony D  Baye
Subject: Re: Fractal screen
Date: 9 Aug 2015 00:45:00
Message: <web.55c6d99f771bab4d2aaea5cb0@news.povray.org>
"Samuel Benge" <stb### [at] hotmailcom> wrote:
> "Anthony D. Baye" <Sha### [at] spamnomorehotmailcom> wrote:
> > "Samuel Benge" <stb### [at] hotmailcom> wrote:
> > > "Samuel Benge" <stb### [at] hotmailcom> wrote:
> > > > Maybe I'll get something going and upload it to glslsandbox.
> > >
> > > OK, here's something if anyone's interested: http://glslsandbox.com/e#27058.0
> > >
> > > You'll have to place the mouse in the lower left corner to properly initialize
> > > the layers (goofy mistake). Seeds are automatically placed under the mouse
> > > cursor.
> > >
> > > The effect tends to be large-scale compared with other diffusion-limited
> > > aggregation setups, but it can be tweaked by changing the settings.
> >
> > neat. But is there a way to add constructive interference?  It could make a
> > great simulator for frost, if you could do that.
>
> I was thinking about another version that adds a water tank/ripples effect to
> the solution... is that what you mean? It would be interesting to see how the
> solid layer builds faster in areas of the solution where it's concentrated due
> to CI. Hm...

mostly, I was thinking that the end result would look less like a voronoi
diagram.

to have it really look like frost, it would have to grow in spikes that get
wider as they get longer.  I have no idea how you'd do that...

Regards,
A.D.B.


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From: Nekar Xenos
Subject: Re: Fractal screen
Date: 9 Aug 2015 01:30:13
Message: <op.x225kglqufxv4h@xena>
On Sun, 09 Aug 2015 00:49:03 +0200, Samuel Benge <stb### [at] hotmailcom>  
wrote:

> "Samuel Benge" <stb### [at] hotmailcom> wrote:
>> Maybe I'll get something going and upload it to glslsandbox.
>
> OK, here's something if anyone's interested:  
> http://glslsandbox.com/e#27058.0
>
> You'll have to place the mouse in the lower left corner to properly  
> initialize
> the layers (goofy mistake). Seeds are automatically placed under the  
> mouse
> cursor.
>
> The effect tends to be large-scale compared with other diffusion-limited
> aggregation setups, but it can be tweaked by changing the settings.
>
>
Beautiful.

It would be nice to have as a Pov-Ray texture.

-- 
-Nekar Xenos-


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From: Samuel Benge
Subject: Re: Fractal screen
Date: 9 Aug 2015 14:40:00
Message: <web.55c79e12771bab4db426f96a0@news.povray.org>
"Anthony D. Baye" <Sha### [at] spamnomorehotmailcom> wrote:
> "Samuel Benge" <stb### [at] hotmailcom> wrote:
> > I was thinking about another version that adds a water tank/ripples effect to
> > the solution... is that what you mean? It would be interesting to see how the
> > solid layer builds faster in areas of the solution where it's concentrated due
> > to CI. Hm...
>
> mostly, I was thinking that the end result would look less like a voronoi
> diagram.

It could be done, of course. Not yet sure how I'd go about it though...

> to have it really look like frost, it would have to grow in spikes that get
> wider as they get longer.  I have no idea how you'd do that...

Either reduce the amount of solution consumed, increase the growth rate, or do
both.

And for water crystals, it helps if the system uses a neighborhood that tests
cells six directions from center:

..oo
ooo
oo.

The result has a six-fold symmetry but ends up skewed, so to look good the final
image would need to be transformed.


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From: Samuel Benge
Subject: Re: Fractal screen
Date: 9 Aug 2015 14:50:00
Message: <web.55c79fd4771bab4db426f96a0@news.povray.org>
"Nekar Xenos" <nek### [at] gmailcom> wrote:
> On Sun, 09 Aug 2015 00:49:03 +0200, Samuel Benge <stb### [at] hotmailcom>
> wrote:
> >
> > OK, here's something if anyone's interested:
> > http://glslsandbox.com/e#27058.0
> >
> > You'll have to place the mouse in the lower left corner to properly
> > initialize
> > the layers (goofy mistake). Seeds are automatically placed under the
> > mouse
> > cursor.
> >
> > The effect tends to be large-scale compared with other diffusion-limited
> > aggregation setups, but it can be tweaked by changing the settings.
> >
> Beautiful.

Thanks.

> It would be nice to have as a Pov-Ray texture.

You could always take a screenshot, crop out the window frame, and remove the
blue channel.

Alternatively, it can all be done procedurally in POV, if you're prepared to
render many, many frames, or endure an hours-long parse time :P


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From: scott
Subject: Re: Fractal screen
Date: 10 Aug 2015 03:02:36
Message: <55c84c8c$1@news.povray.org>
> OK, so some people around here work with LCDs...
>
> We've got a laptop at work with a cracked screen. Around where the crack
> is, the pixels are all black. Which isn't surprising. Slightly more
> interesting is the red vertical lines that seem to extend vertically
> outwards from the cracks. Why red? Why every other pixel? Why vertical?
> I have no idea.

It's more than likely due to the column drivers malfunctioning. One 
possible column driver scheme is to use only one DAC for each *pixel* 
column (not sub-pixel) and then multiplex the output between RGB 
subpixels. It saves by a factor of 3 the number of DACs needed and the 
number of wires to/on the panel. What is likely happening is that when 
each row is getting refreshed, the driver is reset as data is clocked 
in, red is likely first and it gets screwed (because all the column 
tracks are broken at the crack so the wrong capacitance and resistance 
or possibly even shorted) and it never manages to switch the output to 
the green and blue columns.

Another possibility, if the drivers are on the glass substrate itself, 
or a bare IC bonded to the glass, is that they got damaged when the 
crack was made.

> What's weirder still is that close to the cracks, the dead pixels
> exhibit a curiously fractal pattern. It looks like some kind of weird
> pixellated plant growth or something. Does anybody have any idea why?

The "growth" bit is because gradually moisture is getting in to the LC 
material through the crack. They are normally completed sealed in, I'm 
not a chemist but I know moisture+LC is bad and gives those patterns 
even without a crack. Also does the pattern move when you press around 
the crack? It's likely the cell-gap (distance between the inner two 
faces of glass) has changed due to the crack, that normally needs to be 
very accurately controlled to create a uniform image.


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From: Orchid Win7 v1
Subject: Re: Fractal screen
Date: 11 Aug 2015 13:19:59
Message: <55ca2ebf$1@news.povray.org>
On 08/08/2015 11:49 PM, Samuel Benge wrote:
> OK, here's something if anyone's interested: http://glslsandbox.com/e#27058.0

That's just trippy. Not quite as intricate as some of the 
reaction-diffusion systems I've seen, but mental none the less...


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From: Samuel Benge
Subject: Re: Fractal screen
Date: 11 Aug 2015 14:25:00
Message: <web.55ca3d6f771bab4db426f96a0@news.povray.org>
Orchid Win7 v1 <voi### [at] devnull> wrote:
> On 08/08/2015 11:49 PM, Samuel Benge wrote:
> > OK, here's something if anyone's interested: http://glslsandbox.com/e#27058.0
>
> That's just trippy. Not quite as intricate as some of the
> reaction-diffusion systems I've seen, but mental none the less...

Freudian slip? It /is/ probably more of a reaction-diffusion system than it is a
traditional DLA ;)

More detail can be added by making the following line changes:

line 28: float solSub = 10.0;
line 92: R = 1.1 * Sol;

It looks much darker, though. Also, the resolution can be changed via a pull
down menu in the upper left (the default for all shaders is 2x).


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From: Orchid Win7 v1
Subject: Re: Fractal screen
Date: 11 Aug 2015 17:25:44
Message: <55ca6858$1@news.povray.org>
On 11/08/2015 07:22 PM, Samuel Benge wrote:
> Orchid Win7 v1<voi### [at] devnull>  wrote:
>> That's just trippy. Not quite as intricate as some of the
>> reaction-diffusion systems I've seen, but mental none the less...
>
> Freudian slip? It /is/ probably more of a reaction-diffusion system than it is a
> traditional DLA ;)

It hadn't really registered that it's DLA. It looks like the type of 
organic growth you sometimes see with RD systems.

The difference, of course, is that I understand how DLA works. ;-)


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