Wasn't it Richard who wrote:

>Thanks for the suggestion.  But uv_mapping doesn't seem to work for
>cylinders!

It works for me.

#declare SCALE=<3,2.5,3>;

cylinder { <0, -1, 0>, <0 1 0>, 1
  open
  uv_mapping
  texture {
    pigment {
      image_map {
        gif "myimage.gif"
        interpolate 2
      }
    }
    finish { ambient 1.0 }
    scale SCALE*2  // make texture map isotropic on surface
                   // needed because both inside and outside of cylinder
                   // are painted
  }
  scale SCALE // radius 3, height 5
  translate  <6,2.5,0>
}

>I tried a "sor" object, but couldn't get it to work.  I don't understand
>what the first and last values do in the sor.  Does anyone know how to
>draw a cylinder, without end covers?

The start and end points of a SOR are a bit like the extra points you
need for a cubic_spline. I don't think that it's documented what sort of
spline is actually used for generating a SOR, but it's definitely not a
linear spline. To create the appearance of a linear spline with a SOR,
you can simply double up the end points.

To remove the end covers, use the "open" keyword, just like with
"cylinder".

sor {
  4, <3, 0>,<3, 0>,<3, 5>,<3, 5> open   // radius 3, height 5
  uv_mapping
  texture {
    pigment {
      image_map {
        gif "myimage.gif"
        interpolate 2
      }
    }
    finish { ambient 1.0 }
    scale <0.50, 1.0>  // make texture map isotropic on surface
                  // needed because both inside and outside of cylinder
                  // are painted
  }
}

-- 
Mike Williams
Gentleman of Leisure

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