POV-Ray : Newsgroups : povray.binaries.images : Spiral Server Time
9 Oct 2026 12:48:46 EDT (-0400)
  Spiral (Message 1 to 26 of 26)  
From: m@b
Subject: Spiral
Date: 2 Feb 2022 06:19:54
Message: <61fa68da@news.povray.org>
I saw this 
<https://publicdomainreview.org/collection/mellan-sudarium-of-saint-veronica> 

And I made this:


Post a reply to this message


Attachments:
Download 'spiral 01a.png' (165 KB)

Preview of image 'spiral 01a.png'
spiral 01a.png


 

From: Mr
Subject: Re: Spiral
Date: 2 Feb 2022 08:40:01
Message: <web.61fa895fc95e657516086ed06830a892@news.povray.org>
"m@b" <sai### [at] googlemailcom> wrote:
> I saw this
> <https://publicdomainreview.org/collection/mellan-sudarium-of-saint-veronica>
>
> And I made this:

Hmm if I had to do that, I wouldn't know where to start from... is it a sphere
sweep?


Post a reply to this message

From: Dave Blandston
Subject: Re: Spiral
Date: 2 Feb 2022 16:00:00
Message: <web.61faf04cc95e65752636f1af607c1b34@news.povray.org>
"m@b" <sai### [at] googlemailcom> wrote:
> I saw this
> <https://publicdomainreview.org/collection/mellan-sudarium-of-saint-veronica>
>
> And I made this:


That's awesome! Is there a limitation to increasing the tightness of the spiral?
An animated version might be very interesting.

I'm going to guess sphere_sweep too with the radii based on the brightness of
samples from a source image.

Kind regards,
Dave Blandston


Post a reply to this message

From: Thomas de Groot
Subject: Re: Spiral
Date: 3 Feb 2022 02:41:25
Message: <61fb8725$1@news.povray.org>
Op 02/02/2022 om 12:19 schreef m@b:
> I saw this 
> <https://publicdomainreview.org/collection/mellan-sudarium-of-saint-veronica> 
> 
> And I made this:
> 
> 
Well done indeed; now for an even finer line ;-)

Not the same, but this reminds me of Kenneth's airbrush technique (2008, 
iirc). I am unable to find the exact post here.

-- 
Thomas


Post a reply to this message

From: m@b
Subject: Re: Spiral
Date: 3 Feb 2022 07:07:48
Message: <61fbc594$1@news.povray.org>
On 03/02/2022 4:57 am, Dave Blandston wrote:
> "m@b" <sai### [at] googlemailcom> wrote:
>> I saw this
>> <https://publicdomainreview.org/collection/mellan-sudarium-of-saint-veronica>
>>
>> And I made this:
> 
> 
> That's awesome! Is there a limitation to increasing the tightness of the spiral?


No limits - everything is adjustable.
> An animated version might be very interesting.

Here you go <https://youtu.be/NBIKgOxd9l0>
(In YouTube you can right-click and chose loop)

> 
> I'm going to guess sphere_sweep too with the radii based on the brightness of
> samples from a source image.


Close - it's a chain of cylinders. The problem with sphere sweeps is 
that you need to know the number of spheres before you can call it :-)


Post a reply to this message

From: Cousin Ricky
Subject: Re: Spiral
Date: 3 Feb 2022 08:36:28
Message: <61fbda5c$1@news.povray.org>
On 2022-02-03 08:07 (-4), m@b wrote:
> On 03/02/2022 4:57 am, Dave Blandston wrote:
>>
>> I'm going to guess sphere_sweep too with the radii based on the
>> brightness of
>> samples from a source image.
> 
> 
> Close - it's a chain of cylinders. The problem with sphere sweeps is
> that you need to know the number of spheres before you can call it :-)

A clear violation of /The Elements of Programming Style./  As the book
says, computers are better at counting than people are.

The experimental spline feature doesn't make you count; I suppose this
reflects the maturation of the development team over time.


Post a reply to this message

From: Cousin Ricky
Subject: Re: Spiral
Date: 3 Feb 2022 10:19:58
Message: <61fbf29e$1@news.povray.org>
On 2022-02-02 07:19 (-4), m@b wrote:
> I saw this
> <https://publicdomainreview.org/collection/mellan-sudarium-of-saint-veronica>
> 
> And I made this:

Still tuning the macro, but it's essentially done.  This image is made
with spheres and cylinders, but it can easily be switched to a sphere_sweep.


Post a reply to this message


Attachments:
Download 'rsocp-spiral.jpg' (160 KB)

Preview of image 'rsocp-spiral.jpg'
rsocp-spiral.jpg


 

From: Cousin Ricky
Subject: Re: Spiral
Date: 3 Feb 2022 14:04:29
Message: <61fc273d@news.povray.org>
On 2022-02-03 11:19 (-4), Cousin Ricky wrote:
> On 2022-02-02 07:19 (-4), m@b wrote:
>> I saw this
>> <https://publicdomainreview.org/collection/mellan-sudarium-of-saint-veronica>
>>
>> And I made this:
> 
> Still tuning the macro, but it's essentially done.  This image is made
> with spheres and cylinders, but it can easily be switched to a sphere_sweep.

Another, plus color channel renders.  And my hair appears to be thinning.


Post a reply to this message


Attachments:
Download 'me-pats-spiral.jpg' (222 KB) Download 'me-pats-spiral1.png' (163 KB) Download 'me-pats-spiral2.png' (164 KB) Download 'me-pats-spiral3.png' (163 KB)

Preview of image 'me-pats-spiral.jpg'
me-pats-spiral.jpg

Preview of image 'me-pats-spiral1.png'
me-pats-spiral1.png

Preview of image 'me-pats-spiral2.png'
me-pats-spiral2.png

Preview of image 'me-pats-spiral3.png'
me-pats-spiral3.png


 

From: Dave Blandston
Subject: Re: Spiral
Date: 3 Feb 2022 15:25:00
Message: <web.61fc3a0cc95e65752636f1af607c1b34@news.povray.org>
"m@b" <sai### [at] googlemailcom> wrote:
> No limits - everything is adjustable.
> > An animated version might be very interesting.
>
> Here you go <https://youtu.be/NBIKgOxd9l0>
> (In YouTube you can right-click and chose loop)
>
> >
> > I'm going to guess sphere_sweep too with the radii based on the brightness of
> > samples from a source image.
>
>
> Close - it's a chain of cylinders. The problem with sphere sweeps is
> that you need to know the number of spheres before you can call it :-)


Spectacular!


Post a reply to this message

From: William F Pokorny
Subject: Re: Spiral
Date: 3 Feb 2022 15:59:53
Message: <61fc4249$1@news.povray.org>
On 2/3/22 14:04, Cousin Ricky wrote:
> Another, plus color channel renders.  And my hair appears to be thinning.

Cool.

You're better off than me. :-) I've taken to wearing toboggan hats 
inside and out during the colder months. My head gets cold otherwise. 
One of a few clues I've no longer got enough blood circulation to my brain.

Freezing rain, sleet & wet snow falling outside here. Yuck. :-(

Bill P.


Post a reply to this message

From: Jörg "Yadgar" Bleimann
Subject: Re: Spiral
Date: 5 Feb 2022 10:57:49
Message: <61fe9e7d@news.povray.org>
Hi(gh)!

On 03.02.22 08:41, Thomas de Groot wrote:

> Not the same, but this reminds me of Kenneth's airbrush technique (2008, 
> iirc). I am unable to find the exact post here.

Did you mean this:


Post a reply to this message


Attachments:
Download '2008-05-12 fuzzy logic (kenneth).jpg' (413 KB)

Preview of image '2008-05-12 fuzzy logic (kenneth).jpg'
2008-05-12 fuzzy logic (kenneth).jpg


 

From: Jörg "Yadgar" Bleimann
Subject: Re: Spiral
Date: 5 Feb 2022 11:07:03
Message: <61fea0a7$1@news.povray.org>
Hi(gh)!

On 03.02.22 21:59, William F Pokorny wrote:

> Freezing rain, sleet & wet snow falling outside here. Yuck. :-(

Df and Cf climates close to D suck! I prefer Csa... and, luckily, global 
warming will bring the Mediterranean to Cologne!

See you in Khyberspace!

Yadgar


Post a reply to this message

From: Thomas de Groot
Subject: Re: Spiral
Date: 6 Feb 2022 02:20:23
Message: <61ff76b7@news.povray.org>
Op 05/02/2022 om 16:57 schreef Jörg "Yadgar" Bleimann:
> Hi(gh)!
> 
> On 03.02.22 08:41, Thomas de Groot wrote:
> 
>> Not the same, but this reminds me of Kenneth's airbrush technique 
>> (2008, iirc). I am unable to find the exact post here.
> 
> Did you mean this:
> 

I was thinking this:


-- 
Thomas


Post a reply to this message


Attachments:
Download 'kenneth airbrush.png' (93 KB) Download 'kenneth airbrush_linear.png' (139 KB)

Preview of image 'kenneth airbrush.png'
kenneth airbrush.png

Preview of image 'kenneth airbrush_linear.png'
kenneth airbrush_linear.png


 

From: Thomas de Groot
Subject: Re: Spiral
Date: 6 Feb 2022 02:23:45
Message: <61ff7781@news.povray.org>
Op 06/02/2022 om 08:20 schreef Thomas de Groot:
> Op 05/02/2022 om 16:57 schreef Jörg "Yadgar" Bleimann:
>> Hi(gh)!
>>
>> On 03.02.22 08:41, Thomas de Groot wrote:
>>
>>> Not the same, but this reminds me of Kenneth's airbrush technique 
>>> (2008, iirc). I am unable to find the exact post here.
>>
>> Did you mean this:
>>
> 
> I was thinking this:
> 
or this:



-- 
Thomas


Post a reply to this message


Attachments:
Download 'airbrush.png' (205 KB)

Preview of image 'airbrush.png'
airbrush.png


 

From: David Buck
Subject: Re: Spiral
Date: 6 Feb 2022 10:22:44
Message: <61ffe7c4$1@news.povray.org>
This makes me wonder if you could get the illusion of a full-color image 
by having three spirals - one red, one green and one blue - that are 
separate but which spiral out together.

David

On 2022-02-03 2:04 p.m., Cousin Ricky wrote:
> On 2022-02-03 11:19 (-4), Cousin Ricky wrote:
>> On 2022-02-02 07:19 (-4), m@b wrote:
>>> I saw this
>>> <https://publicdomainreview.org/collection/mellan-sudarium-of-saint-veronica>
>>>
>>> And I made this:
>>
>> Still tuning the macro, but it's essentially done.  This image is made
>> with spheres and cylinders, but it can easily be switched to a sphere_sweep.
> 
> Another, plus color channel renders.  And my hair appears to be thinning.


Post a reply to this message

From: Cousin Ricky
Subject: Re: Spiral
Date: 6 Feb 2022 12:54:37
Message: <62000b5d$1@news.povray.org>
On 2022-02-06 11:22 (-4), David Buck wrote:
> This makes me wonder if you could get the illusion of a full-color image
> by having three spirals - one red, one green and one blue - that are
> separate but which spiral out together.

I'm sure it's possible, although it would need some sort of value
inversion somewhere.  A naive application would have, say, redder
(lighter) areas with a thicker (darker) line.  One quick, if somewhat
goth, fix would be to just have a black background.

> On 2022-02-03 2:04 p.m., Cousin Ricky wrote:
>>
>> Another, plus color channel renders.  And my hair appears to be thinning.

P.S. I believe this is our first direct communication, so let me take
this opportunity to thank you for DKBTrace and POV-Ray.


Post a reply to this message

From: David Buck
Subject: Re: Spiral
Date: 6 Feb 2022 16:07:21
Message: <62003889$1@news.povray.org>
I'm happy that I've been able to play a part in this project.  It's been 
a fun ride and still a source of pride for me.

David

On 2022-02-06 12:54 p.m., Cousin Ricky wrote:
> P.S. I believe this is our first direct communication, so let me take
> this opportunity to thank you for DKBTrace and POV-Ray.


Post a reply to this message

From: Cousin Ricky
Subject: Re: Spiral
Date: 8 Feb 2022 16:40:50
Message: <6202e362$1@news.povray.org>
On 2022-02-03 11:19 (-4), Cousin Ricky wrote:
> 
> Still tuning the macro, but it's essentially done.  This image is made
> with spheres and cylinders, but it can easily be switched to a sphere_sweep.

Spheres and cones, actually.  My macro calls SphereSweep from the Object
Collection, and on the quoted post I wasn't thinking about how
SphereSweep did its job.

I was planning to wean my macro off SphereSweep, but then it occurred to
me that a sudden change in color might be too drastic a change in sphere
sizes to connect with a cone.  I'm talking degenerate cone and square
root of a negative number parse errors here.  SphereSweep handles these
complications automatically, so I'm just going to keep it as a prerequisite.


Post a reply to this message


Attachments:
Download 'spiral_cones-pbi.jpg' (19 KB)

Preview of image 'spiral_cones-pbi.jpg'
spiral_cones-pbi.jpg


 

From: Kenneth
Subject: Re: Spiral
Date: 10 Feb 2022 13:35:00
Message: <web.620559d3c95e65754cef624e6e066e29@news.povray.org>
Thomas de Groot <tho### [at] degrootorg> wrote:
>
> Not the same, but this reminds me of Kenneth's airbrush technique
> (2008, iirc). I am unable to find the exact post here.
> ...
> I was thinking this:
>

Sorry for not posting here earlier; I was totally absorbed in running camera
'normal' experiments.

Hmm, I don't remember posting those images, although they look like the
experiments you and I did in my long-ago post (the one that Yadgar referenced).
Perhaps from a different 'Kenneth'? I searched all of the image posts for 2008
and didn't see another fellow by that name. TWO users named Kenneth??
Impossible! :-P

Anyway...I really like these spiral experiments. I was thinking about the
earlier suggestion of somehow using the technique to reproduce a full-color
photo-- perhaps by making separate spirals of the image's 3 separate color
channels (with the spirals colored red/green/blue), but having different
spacings or gaps between the spirals so that they sort of 'blend together' in
the viewer's eye. I haven't thought this through in detail, though. By using
different spiral 'frequencies? Maybe it's not possible geometrically.


Post a reply to this message

From: m@b
Subject: Re: Spiral
Date: 11 Feb 2022 02:20:29
Message: <62060e3d@news.povray.org>
On 06/02/2022 11:22 pm, David Buck wrote:
> This makes me wonder if you could get the illusion of a full-color image 
> by having three spirals - one red, one green and one blue - that are 
> separate but which spiral out together.
> 
> David

It's quick and dirty, but here it is, 3 spirals, one red, one green and 
one blue:


Post a reply to this message


Attachments:
Download 'spiral 04a.png' (143 KB) Download 'spiral 04b.png' (116 KB)

Preview of image 'spiral 04a.png'
spiral 04a.png

Preview of image 'spiral 04b.png'
spiral 04b.png


 

From: Thomas de Groot
Subject: Re: Spiral
Date: 11 Feb 2022 02:36:47
Message: <6206120f$1@news.povray.org>
Op 10/02/2022 om 19:31 schreef Kenneth:
> Thomas de Groot <tho### [at] degrootorg> wrote:
>>
>> Not the same, but this reminds me of Kenneth's airbrush technique
>> (2008, iirc). I am unable to find the exact post here.
>> ...
>> I was thinking this:
>>
> 
> Sorry for not posting here earlier; I was totally absorbed in running camera
> 'normal' experiments.
> 
> Hmm, I don't remember posting those images, although they look like the
> experiments you and I did in my long-ago post (the one that Yadgar referenced).
> Perhaps from a different 'Kenneth'? I searched all of the image posts for 2008
> and didn't see another fellow by that name. TWO users named Kenneth??
> Impossible! :-P
> 
Sorry, a little misunderstanding here. The images were by me; the 
technique was yours ;-)

Probably what Yadgar mentioned. Must have been around July 2008...

> Anyway...I really like these spiral experiments. I was thinking about the
> earlier suggestion of somehow using the technique to reproduce a full-color
> photo-- perhaps by making separate spirals of the image's 3 separate color
> channels (with the spirals colored red/green/blue), but having different
> spacings or gaps between the spirals so that they sort of 'blend together' in
> the viewer's eye. I haven't thought this through in detail, though. By using
> different spiral 'frequencies? Maybe it's not possible geometrically.
> 

By using eval_pigment perhaps, or a pigment function, to evaluate the 
colour, then using the result to change the colour of the individual 
cones in the spiral...?

-- 
Thomas


Post a reply to this message

From: Thomas de Groot
Subject: Re: Spiral
Date: 11 Feb 2022 02:40:58
Message: <6206130a$1@news.povray.org>
Op 11/02/2022 om 08:20 schreef m@b:
> On 06/02/2022 11:22 pm, David Buck wrote:
>> This makes me wonder if you could get the illusion of a full-color 
>> image by having three spirals - one red, one green and one blue - that 
>> are separate but which spiral out together.
>>
>> David
> 
> It's quick and dirty, but here it is, 3 spirals, one red, one green and 
> one blue:

Yes! Excellent!

I wondered earlier, in my answer to Kenneth here, if it would be 
possible to tint differently individual cones in a spiral? That way only 
one spiral would be needed, but I guess that is not allowed.

-- 
Thomas


Post a reply to this message

From: Kenneth
Subject: Re: Spiral
Date: 11 Feb 2022 11:35:00
Message: <web.62068ffac95e65754cef624e6e066e29@news.povray.org>
"m@b" <sai### [at] googlemailcom> wrote:
> On 06/02/2022 11:22 pm, David Buck wrote:
> > This makes me wonder if you could get the illusion of a full-color image
> > by having three spirals - one red, one green and one blue - that are
> > separate but which spiral out together.
> >
> > David
>
> It's quick and dirty, but here it is, 3 spirals, one red, one green and
> one blue:

It worked! That is really cool.

I half-thought that the solution might be to simply scale each successive spiral
slightly larger. But instead, it looks like each spiral begins (in the center)
at 120-degree rotations from each other. Great! I imagine that *more* than 3
colors could be used with the same technique, by simply dividing-up the
rotations differently (and making the spirals appropriately thinner, maybe.)
Like, 6 spirals-colors would use 360/6 rotation adjustments.


Post a reply to this message

From: David Buck
Subject: Re: Spiral
Date: 11 Feb 2022 20:01:27
Message: <620706e7$1@news.povray.org>
Wow.  I think that works really well.  If you look closely, you just see 
red, green and blue but an overall glance gives you subtle shades of 
color.  Cool!

David Buck

On 2022-02-11 2:20 a.m., m@b wrote:
> On 06/02/2022 11:22 pm, David Buck wrote:
>> This makes me wonder if you could get the illusion of a full-color 
>> image by having three spirals - one red, one green and one blue - that 
>> are separate but which spiral out together.
>>
>> David
> 
> It's quick and dirty, but here it is, 3 spirals, one red, one green and 
> one blue:


Post a reply to this message

From: Bald Eagle
Subject: Re: Spiral
Date: 12 Feb 2022 10:40:00
Message: <web.6207d45fc95e65751f9dae3025979125@news.povray.org>
David Buck <dav### [at] simberoncom> wrote:
> Wow.  I think that works really well.  If you look closely, you just see
> red, green and blue but an overall glance gives you subtle shades of
> color.  Cool!


Right, I saw this effect a while ago, and hadn't gotten around to posting it.
Now it seems like it might have some utility to inspire some experimentation.
:)

https://petapixel.com/2019/07/31/this-black-and-white-photo-uses-color-grid-lines-to-trick-your-brain/

Pretty cool effect / illusion.

I wonder if all 3 spirals could be coincident or layered with rgbf pigments.

Also wondering what a single spiral of closely arranged spheres would look like
with full rgb pigmentation of each individual sphere...


Post a reply to this message

From: Cousin Ricky
Subject: Re: Spiral
Date: 12 Feb 2022 16:56:18
Message: <62082d02@news.povray.org>
On 2022-02-06 11:22 (-4), David Buck wrote:
> This makes me wonder if you could get the illusion of a full-color image
> by having three spirals - one red, one green and one blue - that are
> separate but which spiral out together.

Turns out it wasn't so difficult.

The file sizes for these things are tricky.  Quite often, the PNGs are
smaller than the JPEGs, though I can /sometimes/ get the JPEGs smaller
by using compression 75.


Post a reply to this message


Attachments:
Download 'me-pats-cspiral.png' (240 KB)

Preview of image 'me-pats-cspiral.png'
me-pats-cspiral.png


 

Copyright 2003-2023 Persistence of Vision Raytracer Pty. Ltd.