POV-Ray : Newsgroups : povray.binaries.images : Towards Tek's Isosurface City Server Time
3 Mar 2024 18:03:16 EST (-0500)
  Towards Tek's Isosurface City (Message 1 to 6 of 6)  
From: Tor Olav Kristensen
Subject: Towards Tek's Isosurface City
Date: 27 Dec 2023 22:50:00
Message: <web.658cef0e2f5f1a9e2ba5690489db30a9@news.povray.org>
The attached image is the results of my attempts to find out how Tek made the
images he posted in this thread:

From: Tek
Subject: Isosurface City revistied (WIP-maybe)
Date: 2008-03-25 19:24:01
https://news.povray.org/povray.binaries.images/thread/%3C47e997a1%40news.povray.org%3E/

AFAIK he did not post the code anywhere in here - and his web pages seems to be
down.

I've not yet figured out what pattern he used to make the windows.

--
Tor Olav
http://subcube.com
https://github.com/t-o-k


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Attachments:
Download 'towards teks isosurface city.png' (1864 KB)

Preview of image 'towards teks isosurface city.png'
towards teks isosurface city.png


 

From: Mr
Subject: Re: Towards Tek's Isosurface City
Date: 28 Dec 2023 09:45:00
Message: <web.658d898796cac28216086ed06830a892@news.povray.org>
"Tor Olav Kristensen" <tor### [at] TOBEREMOVEDgmailcom> wrote:
> The attached image is the results of my attempts to find out how Tek made the
> images he posted in this thread:
>
> From: Tek
> Subject: Isosurface City revistied (WIP-maybe)
> Date: 2008-03-25 19:24:01
>
https://news.povray.org/povray.binaries.images/thread/%3C47e997a1%40news.povray.org%3E/
>
> AFAIK he did not post the code anywhere in here - and his web pages seems to be
> down.
>
> I've not yet figured out what pattern he used to make the windows.
>
> --
> Tor Olav
> http://subcube.com
> https://github.com/t-o-k

This looks close, but increasing the relative height of buildings compared to
their base areas gave them more orthogonal / artificial looking overall lines.

by the looks of it I'm assuming that the core of your procedural is a Crackle
pattern... If so, did you use metric 4 to give it more square appearance ? Some
metric superior to 25 would end up providing even "squarer" angled cells.

Using two planimetric components of the vector "form <x,y,z>" (depending on the
orientation of your scene) may also allow you to control the convexity of cells.

Thanks for your endeavour !

These are base on old tweaks I had tried when comparing Blender internal Voronoi
with pov's crackle procedural textures for the purpose of Blender to POV export.
(draft notes attached)


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Attachments:
Download 'blend2povvoronoi.pdf' (441 KB)

From: Bald Eagle
Subject: Re: Towards Tek's Isosurface City
Date: 28 Dec 2023 11:10:00
Message: <web.658d9cc996cac2821f9dae3025979125@news.povray.org>
"Mr" <m******r******at_hotmail_dot_fr> wrote:
> "Tor Olav Kristensen" <tor### [at] TOBEREMOVEDgmailcom> wrote:
> > The attached image is the results of my attempts to find out how Tek made the
> > images he posted in this thread:
.....
> > I've not yet figured out what pattern he used to make the windows.

Hi TOK - thanks for the recent advice!  :)
I have been rewiring my brain for the past several years, but still need to do
more to get better at functional programming. It's gonna take me a while to
unravel this one and implement it in SDL:
https://www.shadertoy.com/view/fsyyzt


Kenneth was working on a very similar building scene a while back - maybe you
may find some clues there.

http://news.povray.org/povray.binaries.images/thread/%3C59766804%40news.povray.org%3E/

> These are base on old tweaks I had tried when comparing Blender internal Voronoi
> with pov's crackle procedural textures for the purpose of Blender to POV export.
> (draft notes attached)

Hi Maurice - I'd be interested to see what work you've done with the Voronoi
pattern, and if you have a version that infinitely tiles.  I haven't fully
worked out the details of that part yet.
I did manage to work out full-color solid cells, but my colors don't tile along
with the repeating pattern for some reason.

I have also worked out many of the source-code patterns in SDL, if you're
interested in seeing my code for those.


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From: Kenneth
Subject: Re: Towards Tek's Isosurface City
Date: 29 Dec 2023 15:10:00
Message: <web.658f273996cac2829b4924336e066e29@news.povray.org>
"Tor Olav Kristensen" <tor### [at] TOBEREMOVEDgmailcom> wrote:

>
> AFAIK he did not post the code anywhere in here - and his web pages seems
> to be down.
>
> I've not yet figured out what pattern he used to make the windows.
>

Your attempt looks quite good as-is!

In the newsgroups, this is what I have found. I already had links to a few of
these:

his early renders  and code, March 2002... "the power of crackle"...
https://news.povray.org/povray.binaries.images/thread/%3C3C8C6B5A.A940E282%40gmx.de%3E/

and

https://news.povray.org/povray.binaries.scene-files/thread/%3C3c8bf694%40news.povray.org%3E/?ttop=442431&toff=950

Another render from March 18 2002...
https://news.povray.org/povray.binaries.images/thread/%3C3c97ab74%241%40news.povray.org%3E/

and his code, March 19 2002-- he called it 'Crackle City'...
https://news.povray.org/povray.binaries.scene-files/thread/%3C3c96f0bc%40news.povray.org%3E/?ttop=442431&toff=950

from August 2009... something he called 'Greeble City'...
https://news.povray.org/povray.binaries.scene-files/thread/%3C4a78a444%40news.povray.org%3E/?ttop=442431&toff=300

and renders of same...
https://news.povray.org/povray.binaries.images/thread/%3C4a78a486%40news.povray.org%3E/

----------------------
Another from March 2002...
https://news.povray.org/povray.binaries.images/thread/%3C3c96585e%40news.povray.org%3E/

from July 2008...
https://news.povray.org/povray.binaries.images/thread/%3C488e5300%40news.povray.org%3E/?mtop=280940&moff=20


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From: Tor Olav Kristensen
Subject: Re: Towards Tek's Isosurface City
Date: 29 Dec 2023 21:50:00
Message: <web.658f852e96cac282c342de0989db30a9@news.povray.org>
"Mr" <m******r******at_hotmail_dot_fr> wrote:
> "Tor Olav Kristensen" <tor### [at] TOBEREMOVEDgmailcom> wrote:
> > The attached image is the results of my attempts to find out how Tek made the
> > images he posted in this thread:
> >
> > From: Tek
> > Subject: Isosurface City revistied (WIP-maybe)
> > Date: 2008-03-25 19:24:01
> >
https://news.povray.org/povray.binaries.images/thread/%3C47e997a1%40news.povray.org%3E/
> >
> > AFAIK he did not post the code anywhere in here - and his web pages seems to be
> > down.
> >
> > I've not yet figured out what pattern he used to make the windows.
> >
> > --
> > Tor Olav
> > http://subcube.com
> > https://github.com/t-o-k
>
> This looks close, but increasing the relative height of buildings compared to
> their base areas gave them more orthogonal / artificial looking overall lines.

I'm struggling a bit to compare the height to base ratio of buildings in
Tek's an my renders.

I'll decrease the building heights in future renders.


> by the looks of it I'm assuming that the core of your procedural is a Crackle
> pattern... If so, did you use metric 4 to give it more square appearance ?

Yes, it's a crackle pattern, but with metric 1, as Tek mentioned,

For the buildings I'm using form <-1, 0, +1> and for the ground I'm using
form <-1, +1, 0>.


> metric superior to 25 would end up providing even "squarer" angled cells.
>
> Using two planimetric components of the vector "form <x,y,z>" (depending on the
> orientation of your scene) may also allow you to control the convexity of cells.

This sounds interesting. I did not know that it was possible to make the
crackle cells more "squarer".

I know very little about crackle patterns. I tried to read about crackle
in the POV-Ray documentation, but the explanation of the parameters where
to cryptic for me.

I'll experiment with those metric values.


> Thanks for your endeavour !

No problem. It's an interesting challenge to try to find out how Tek might
have made his latest city images.


> These are base on old tweaks I had tried when comparing Blender internal Voronoi
> with pov's crackle procedural textures for the purpose of Blender to POV export.
> (draft notes attached)

Thank you. I'll have a look at your notes.

I remember now that I once read a little about Voronoi diagrams and that
they are related to crackle patterns.

--
Tor Olav
http://subcube.com
https://github.com/t-o-k


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From: Tor Olav Kristensen
Subject: Re: Towards Tek's Isosurface City
Date: 2 Jan 2024 20:50:00
Message: <web.6594bc6c96cac2824238d36c89db30a9@news.povray.org>
"Kenneth" <kdw### [at] gmailcom> wrote:
> "Tor Olav Kristensen" <tor### [at] TOBEREMOVEDgmailcom> wrote:
>
> >
> > AFAIK he did not post the code anywhere in here - and his web pages seems
> > to be down.
> >
> > I've not yet figured out what pattern he used to make the windows.
> >
>
> Your attempt looks quite good as-is!
>
> In the newsgroups, this is what I have found. I already had links to a few of
> these:
>
> his early renders  and code, March 2002... "the power of crackle"...
>...

Thank you for all those links Kenneth. I must have done a poor job when looking
for relevant code.

--
Tor Olav
http://subcube.com
https://github.com/t-o-k


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