I would like to make with POV a non-traditional spherical chess board. I
already have the 1-parametric description of the lines that play the role of
sides of the squares. The intersections of such lines are the corners of the
squares, for which I would like to use two different patterns, of course.

I have some idea about how to do it, but does not seem very practical. Any
suggestions?


Thanks in advance.


--


Universidad Complutense de Madrid


Avda. Complutense s/n
28040 Madrid
Tlf. 91 394 44 11

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The easiest way to do that depends a bit upon the exact geometry of your 
squares. So you should precise a bit.

Until some specialist answers you, I can give some tracks:
- You can combine a radial and gradient textures.
- You can use UV mapping I think, but I don't know much on how to use it.
- You can generate your sphere as a mesh and assign the proper texture 
to each triangle.

I would go with the first one, it is probably the easiest and more 
efficient solution. Let me know if you need more clues,

JC

Miguel Garcia wrote:
> I would like to make with POV a non-traditional spherical chess board. I
> already have the 1-parametric description of the lines that play the role of
> sides of the squares. The intersections of such lines are the corners of the
> squares, for which I would like to use two different patterns, of course.
> 
> I have some idea about how to do it, but does not seem very practical. Any
> suggestions?
> 
> 
> Thanks in advance.
> 
> 
> --


> Universidad Complutense de Madrid
> 

> Avda. Complutense s/n
> 28040 Madrid
> Tlf. 91 394 44 11
> 
>

Post a reply to this message

Is that what you want ?

#declare T_G1=texture {
   pigment {
     gradient y
     color_map {
       [0.0 rgb 1.0]
       [0.5 rgb 1.0]
       [0.5 rgb 0.0]
       [1.0 rgb 0.0]
     }
     scale 1/4
   }
}

#declare T_G2=texture {
   T_G1
   translate <0,1/8,0>
}

sphere {
   <0,1,0>, 1
   texture {
     radial
     frequency 4
     texture_map {
       [0.0 T_G1]
       [0.5 T_G1]
       [0.5 T_G2]
       [1.0 T_G2]
     }
   }
}


Miguel Garcia wrote:
> I would like to make with POV a non-traditional spherical chess board. I
> already have the 1-parametric description of the lines that play the role of
> sides of the squares. The intersections of such lines are the corners of the
> squares, for which I would like to use two different patterns, of course.
> 
> I have some idea about how to do it, but does not seem very practical. Any
> suggestions?
> 
> 
> Thanks in advance.
> 
> 
> --


> Universidad Complutense de Madrid
> 

> Avda. Complutense s/n
> 28040 Madrid
> Tlf. 91 394 44 11
> 
>

Post a reply to this message

"JC (Exether)" <no### [at] spamfr> wrote in message
news:3f66c5f6@news.povray.org...
> The easiest way to do that depends a bit upon the exact geometry of your
> squares. So you should precise a bit.
>
> Until some specialist answers you, I can give some tracks:
> - You can combine a radial and gradient textures.
> - You can use UV mapping I think, but I don't know much on how to use it.

I never heard about it, so I will take a look at it.

> - You can generate your sphere as a mesh and assign the proper texture
> to each triangle.

You are right, I did not think about it. But this is the last thing that I
will try.

Thanks a lot for your ideas.

--

http://www.telefonica.net/web/miguelgdz/index.html

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"JC (Exether)" <no### [at] spamfr> wrote in message
news:3f66c7ba@news.povray.org...
> Is that what you want ?
>
> #declare T_G1=texture {
>    pigment {
>      gradient y
>      color_map {
>        [0.0 rgb 1.0]
>        [0.5 rgb 1.0]
>        [0.5 rgb 0.0]
>        [1.0 rgb 0.0]
>      }
>      scale 1/4
>    }
> }
>
> #declare T_G2=texture {
>    T_G1
>    translate <0,1/8,0>
> }
>
> sphere {
>    <0,1,0>, 1
>    texture {
>      radial
>      frequency 4
>      texture_map {
>        [0.0 T_G1]
>        [0.5 T_G1]
>        [0.5 T_G2]
>        [1.0 T_G2]
>      }
>    }
> }
>
>

Well, no. This is a traditional spherical squared board. I have a different
geometry in mind, where the sides of the squares are not the classical
meridians and paralels. I have the equations of such lines, but nothing
else.

Thanks again.

--

http://www.telefonica.net/web/miguelgdz/index.html

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