Hi,

making nice colormaps can easily become a cumbersome task - especially in the
case of fractal images, where the harmonious arrangement of colors is essential.

Recently I stumbled across a nice little macro of Christophe Bouffartique
(Insects and... Spiderman -
http://www.irtc.org/ftp/pub/stills/2001-06-30/cbspider.zip). He used a photo to
get colormap entries for a wood texture.

With some tweaking this macro takes an image containing 1250 stripes of colors
and returns colormaps with up to 256 entries. The order of the entries can be
turned upside down too.

Ideas came from design, fashion, advertising, cosmetics, fabrics, furnishing,
website layouts, color palette collections, art, graphics, photos (e.g. sunsets
or tropic fishs) etc.

Shown are two examples together with the corresponding colormap.

I posted a similar test scene to pbsf
(http://news.povray.org/povray.binaries.scene-files/thread/%3Cweb.560285cd3b3e676746db0c30%40news.povray.org%3E/
).

Norbert Kern

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Attachments:
Download 'easy_colormapping.jpg' (883 KB)

Preview of image 'easy_colormapping.jpg'

That's very very nice indeed! Gorgeous examples. I shall certainly try 
that out.
-- 
Thomas

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Am 23.09.2015 um 13:02 schrieb Norbert Kern:

> With some tweaking this macro takes an image containing 1250 stripes of colors
> and returns colormaps with up to 256 entries. The order of the entries can be
> turned upside down too.

Fun fact to know: POV-Ray (post-3.7.0) should be fine with more than 256
entries in a whatever_map.

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Thomas de Groot <tho### [at] degrootorg> wrote:
> That's very very nice indeed! Gorgeous examples. I shall certainly try
> that out.
> --
> Thomas

Thank you very much!

Norbert

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clipka <ano### [at] anonymousorg> wrote:

> Fun fact to know: POV-Ray (post-3.7.0) should be fine with more than 256
> entries in a whatever_map.

Good to know - but besides UberPOV, when we'll see an official version?

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Am 23.09.2015 um 17:14 schrieb Norbert Kern:
> clipka <ano### [at] anonymousorg> wrote:
> 
>> Fun fact to know: POV-Ray (post-3.7.0) should be fine with more than 256
>> entries in a whatever_map.
> 
> Good to know - but besides UberPOV, when we'll see an official version?

You mean an official /release/ version?

Can't say. That'll be up to Chris Cason.

I for one consider POV-Ray an ongoing work in progress anyway, now that
it's on GitHub. Whatever is in the "master" branch should be good enough
to go.

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"Norbert Kern" <nor### [at] t-onlinede> wrote:
> Hi,
>
> making nice colormaps can easily become a cumbersome task - especially in the
> case of fractal images, where the harmonious arrangement of colors is essential.
>
> Recently I stumbled across a nice little macro of Christophe Bouffartique
> (Insects and... Spiderman -
> http://www.irtc.org/ftp/pub/stills/2001-06-30/cbspider.zip). He used a photo to
> get colormap entries for a wood texture.
>
> With some tweaking this macro takes an image containing 1250 stripes of colors
> and returns colormaps with up to 256 entries. The order of the entries can be
> turned upside down too.

you, sir, are as amazing as Bouffartique and other greats from the povray
legendarium :thumbsup:

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"nemesis" <nam### [at] gmailcom> wrote:

> you, sir, are as amazing as Bouffartique and other greats from the povray
> legendarium :thumbsup:




Thanx - it's a great compliment.

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By the way, you can avoid the warning messages by deleting 'rgb' before 
eval_pigment () in the macro.

Thomas

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Thomas de Groot <tho### [at] degrootorg> wrote:
> By the way, you can avoid the warning messages by deleting 'rgb' before
> eval_pigment () in the macro.
>
> Thomas


Thanx for the tip!

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