POV-Ray : Newsgroups : povray.binaries.images : UV-coordinate pigment - 1 attachment Server Time: 17 Feb 2019 22:41:38 GMT
  UV-coordinate pigment - 1 attachment (Message 1 to 3 of 3)  
From: Tor Olav Kristensen
Subject: UV-coordinate pigment - 1 attachment
Date: 26 Mar 2003 12:40:08
Message: <Xns934A8B380763Dtorolavkhotmailcom@204.213.191.226>
Of course I had to try ABX' suggestion to make one's
own XYZ to UV mapping functions:

http://news.povray.org/povray.advanced-users/30962/

And after having played around for a while with that
technique, I thought that maybe one could define a
pigment that shows the uv-coordinates "projected"
onto the surface of the shape one are working with.

The attached image shows the result.

A macro; UVcoordPigment() builds this pigment.
Here is how it was called:

object {
  ParametricMesh( ... )
  texture {
    uv_mapping
    UVcoordPigment()
  }
}


Any suggestions or comments ?


Tor Olav


Post a reply to this message


Attachments:
Download 'B-Splines03_09_03.jpg' (103 KB)

Preview of image 'B-Splines03_09_03.jpg'
B-Splines03_09_03.jpg


 

From: ABX
Subject: Re: UV-coordinate pigment - 1 attachment
Date: 26 Mar 2003 13:11:00
Message: <bf938v0ve50rka8b3sovjbtbdmjhl7qike@4ax.com>
On 26 Mar 2003 07:40:08 -0500, Tor Olav Kristensen <tor_olav_kCURLYAhotmail.com>
wrote:
> Of course I had to try ABX' suggestion to make one's
> own XYZ to UV mapping functions:

I have used that idea in my 'random' isosurface maze:
http://news.povray.org/search/advanced/?s=maze&g=povray.binaries.images

> And after having played around for a while with that
> technique, I thought that maybe one could define a
> pigment that shows the uv-coordinates "projected"
> onto the surface of the shape one are working with.

Interesting, you mean red is u, green is v and blue is nothing ?

> Any suggestions or comments ?

Since it is mesh, isn't that already posible with 'traditional' uv_mapping ?

ABX


Post a reply to this message

From: Tor Olav Kristensen
Subject: Re: UV-coordinate pigment - 1 attachment
Date: 26 Mar 2003 13:36:58
Message: <Xns934A94E359AD1torolavkhotmailcom@204.213.191.226>
ABX <abx### [at] abxartpl> wrote in
news:bf938v0ve50rka8b3sovjbtbdmjhl7qike@4ax.com: 

> On 26 Mar 2003 07:40:08 -0500, Tor Olav Kristensen
> <tor_olav_kCURLYAhotmail.com> wrote:
>> Of course I had to try ABX' suggestion to make one's
>> own XYZ to UV mapping functions:
> 
> I have used that idea in my 'random' isosurface maze:
> http://news.povray.org/search/advanced/?s=maze&g=povray.binaries.images

I did not realise that back then. Hmmm... Maybe I could
use this in some of my own isosurfaces.


>> And after having played around for a while with that
>> technique, I thought that maybe one could define a
>> pigment that shows the uv-coordinates "projected"
>> onto the surface of the shape one are working with.
> 
> Interesting, you mean red is u, green is v and blue is nothing ?

Yes.


>> Any suggestions or comments ?
> 
> Since it is mesh, isn't that already posible with 'traditional'
> uv_mapping ? 

It _is_ traditional UV-mapping. Maybe I was a little
unclear about that: No user defined functions are used
to build or map the pigment. It is POV-ray itselt that
does the mapping. My macro just builds the pigment.

(The ParametricMesh() macro defines, as usual, the UV
coordinates for each mesh triangle vertice.)


Tor Olav


Post a reply to this message

Copyright 2003-2008 Persistence of Vision Raytracer Pty. Ltd.