So I have a bicubic patch and I'm trying to apply two marble pattern
textures to it with uv mapping, one rotated 90 degrees from the other.
Unfortunately the rotation causes the pattern to become stretched instead
of being rotated.  Anyone know why and/or how to fix this?

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Wasn't it Mienai who wrote:
>So I have a bicubic patch and I'm trying to apply two marble pattern
>textures to it with uv mapping, one rotated 90 degrees from the other.
>Unfortunately the rotation causes the pattern to become stretched instead
>of being rotated.  Anyone know why and/or how to fix this?

You have to rotate around the z axis only.

(I suppose, theoretically, as a UV mapped texture you ought to rotate
around the W axis, but there isn't one.)

I used 


  uv_mapping
  
  texture {pigment {marble 
    scale 0.1 
    colour_map {[0.5 rgb 1][0.5 rgb x]}
    rotate z*90
  }}
  texture {pigment {marble
    scale 0.1 
    colour_map {[0.5 rgbt 1][0.5 rgb x]}
  }}



-- 
Mike Williams
Gentleman of Leisure

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Mike Williams <nos### [at] econymdemoncouk> wrote:
> You have to rotate around the z axis only.
>
> (I suppose, theoretically, as a UV mapped texture you ought to rotate
> around the W axis, but there isn't one.)
>
> I used
>
>
>   uv_mapping
>
>   texture {pigment {marble
>     scale 0.1
>     colour_map {[0.5 rgb 1][0.5 rgb x]}
>     rotate z*90
>   }}
>   texture {pigment {marble
>     scale 0.1
>     colour_map {[0.5 rgbt 1][0.5 rgb x]}
>   }}
>
>
>
> --
> Mike Williams
> Gentleman of Leisure

Thanks, that was exactly what I was looking for.

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hello,

i want to model cable with 2 parts : cylindrical and part of torus.

for cylindrical, i have no problem. code i use is :

#declare p1 = 8;    // number of helixes 
#declare p2 = 0.25; // number of turns per unit length 
#declare p3 = 1.75; // minor radius
#declare p4 = 1.50; // major radius
#declare p5 = 1.00; // shape parameter
#declare p6 = 1;    // cross section type -> circle
#declare p7 = 0;    // cross section rotation angle

#declare containerSize = 3.20;
#declare maxGradiantValue = 10;

#declare cableFunction = function { f_helix1(x, y, z, p1, p2, p3, p4, 
p5, p6, p7) }

#declare cableCyl = isosurface {
  function { cableFunction(x,y,z) }
  contained_by { 
    box { <+containerSize, 0.00, +containerSize> <-containerSize, 
-cableLen, -containerSize>   }
    }
  max_gradient maxGradiantValue
  }


for "torus part", i do this code :

#declare cableTorus = isosurface {
  function { cableFunction(f_r(x,y,z)-MajorRadius, y, f_th(x,y,z)) }
  contained_by { 
    sphere { 0,*MajorRadius1.2 }
    }
  max_gradient maxGradiantValue
  rotate 90*x 
  }
with MajorRadius = 80.00


... but all the thing a get is a plain torus !!!

anyone can help me ?
thanks

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