"clipka" <nomail@nomail> wrote:
> an additional operation, a so-called warp (more precisely, a repeat warp in this
> case; you probably need two of them). See "3.5.12.6.2  Repeat Warp" in the POV
> 3.6 documentation.

Dang, I completely forgot about repeat warps. Looks like I reinvented the wheel
again... ;-)

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> Dang, I completely forgot about repeat warps. Looks like I reinvented the
> wheel again... ;-)

  I always thought that POV-Ray was specially crafted for people who like to
reinvent the 3D wheel... :)

--
Jaime

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Jaime Vives Piqueres <jai### [at] ignoranciaorg> wrote:

> > Dang, I completely forgot about repeat warps. Looks like I reinvented the
> > wheel again... ;-)
>
>   I always thought that POV-Ray was specially crafted for people who like to
> reinvent the 3D wheel... :)

It's often quicker to do so than go hunting through docs and resources...!

I was making some textures the other day by drawing pictures with spherical and
boxed pigments, then tessellating them. Because I was using pigment functions
to combine the various shapes, it seemed obvious to call them as

fn(x-floor(x), 0, z-floor(z)).x

to get the repetition...

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"Bill Pragnell" <bil### [at] hotmailcom> wrote:
> >   I always thought that POV-Ray was specially crafted for people who like to
> > reinvent the 3D wheel... :)
>
> It's often quicker to do so than go hunting through docs and resources...!
>
> I was making some textures the other day by drawing pictures with spherical and
> boxed pigments, then tessellating them. Because I was using pigment functions
> to combine the various shapes, it seemed obvious to call them as
>
> fn(x-floor(x), 0, z-floor(z)).x
>
> to get the repetition...

Yeah. It seems that most things are actually quite trivial in POV - at least in
the original latin sense, literally meaning "having three ways" ;)

In this case, another one would be to use the pattern as a function image (see
3.5.11.16) without the "once" keyword ;) (didn't test it, but I guess it should
tile like any proper image would)


You know you've been raytracing too long when...
    ... you know every little trick the POV SDL has to offer ;)

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Jaime Vives Piqueres wrote:
>  I always thought that POV-Ray was specially crafted for people who like to
> reinvent the 3D wheel... :)

Or at least the sphere.

-- 
   Darren New, San Diego CA, USA (PST)
   My fortune cookie said, "You will soon be
   unable to read this, even at arm's length."

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Darren New <dne### [at] sanrrcom> wrote:
> Jaime Vives Piqueres wrote:
> >  I always thought that POV-Ray was specially crafted for people who like to
> > reinvent the 3D wheel... :)
>
> Or at least the sphere.

Yeah, those are "tri-vial" as well: You can use POV's standard sphere{}, but
occasionally you are better off with a sperical blob element. And occasionally
you may have reason to model it as an isosurface - or a mesh, for that
matter...

Using bicubic patches to approximate a sphere seems to be a bit difficult
though...

;)

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<yaz### [at] gmxde> wrote:

> While playing around with procedurally generated countries' flags, I
> tried to use them in patterns... and to make it simple in the beginning,
> I started with a checker pattern containing the flags of Palau and
> Trinidad and Tobago:

Here are some procedurally-generated flags I was experimenting with a year  
and a half ago.  The first 3 are:
   - U.S. Virgins Islands, where I live;
   - United States of America, my country of citizenship;
   - Maryland, USA, where I was staying when I made these flags.

I didn't make a Trinidad and Tobago; not enough of a challenge, I guess.   
Instead I submit nearby countries Barbados and St. Vincent and the  
Grenadines.  (I have flags languishing of even closer countries, Venezuela  
(which is a good swim from Trinidad) and Grenada, as well as T&T itself.  
However, they are from my pre-POV-Ray days.)

The colors may seem a bit coolish; the monitor I was using at the time was  
damaged and didn't illuminate properly.

-- 
<Insert witty .sig here>

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Attachments:
Download 'usvi-flag.png' (22 KB) Download 'usa-flag.png' (11 KB) Download 'maryland-flag.png' (4 KB) Download 'barbados-flag.png' (2 KB) Download 'st_vincent-flag.png' (3 KB)

Preview of image 'usvi-flag.png'

Preview of image 'usa-flag.png'

Preview of image 'maryland-flag.png'

Preview of image 'barbados-flag.png'

Preview of image 'st_vincent-flag.png'

"clipka" <nomail@nomail> wrote:

> In this case, another one would be to use the pattern as a function image (see
> 3.5.11.16) without the "once" keyword ;) (didn't test it, but I guess it should
> tile like any proper image would)

Yes indeed; I use that technique quite a bit.

The only problem with a function image is the really odd 'upside-down mirror
image' behavior of the resulting pattern 'slice' (at least when it's used to
make a HF, anyway.) Try making a function image from an image_map to see what I
mean.  This behavior seems to be intrinsic to using a function with *any*
pattern (although, since POV patterns like bozo and such are
random-looking anyway, it's difficult to see this effect.) Awhile ago, I posted
something about all this, with a fix (and I've since found a slightly simpler
fix, but the posted one will do it)...

http://news.povray.org/povray.advanced-users/thread/%3Cweb.47f304325a8bc21378dcad930%40news.povray.org%3E/

KW

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news:49c98018$1@news.povray.org...
> High!
>
> I started with a checker pattern containing the flags of Palau and
> Trinidad and Tobago:
>

Hi Yadgar and CR,

If you code these in a way that's compatible with the 23 already in the 
Object Collection at 
http://lib.povray.org/searchcollection/index2.php?objectName=Flags&contributorTag=chrisb
then we could build a pretty comprehensive set (each is simply defined in 
it's own macro which sets the Flags_Texture identifier using a texture 
scaled to fit a unit square.

It currently contains procedural textures for "Olympic", "UnionJack", 
"UnionFlag1606", "StGeorgesCross", "StAndrewsCross", 
"StPatricksCross","Wales", "Canada", "USA", "Australia", "New Zealand", 
"Ireland", "France", "Belgium", "Italy", "Germany", "Austria", "Luxembourg", 
"Netherlands", "Hungary", "Armenia", "Peru", "Nigeria".

I'd be happy to help put that together if that's something you'd like to do.

Regards,
then Chris B.

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Since we're on pbi:

Chris B.

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Attachments:
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