"Chris B" <nom### [at] nomailcom> wrote:
> "zeycus" <mig### [at] onocom> wrote in message
> news:web.47a44adec0e4bb1b5f201c20@news.povray.org...
> > Hi everybody,
> >
> > I have a bitmap I want to project onto the surface of a sphere. I want to
> > use
> > spherical projection, so that the image is not distorted. The problem is
> > that I
> > want to control the angle covered (measured from the center of the
> > sphere). One
> > solution would be to increase the bitmap size with nothing around, but
> > that is
> > ugly. What is the correct way to do this?
> >
>
> Hi,
>
> Use the 'once' keyword and scale in 'x'  to get a segment (or scale in 'y'
> and translate in 'y' to get a ring around the middle of the sphere).
>
> light_source { <-15,7.5,-15>, rgb 2}
> camera {location <0,3,0> look_at <0,0,0>}
>
> sphere {0,1
>   texture {
>     pigment {
>       image_map {sys "ngtest11.bmp" once}
>       scale 0.6*x
>       rotate x*90
>       warp {spherical
>         orientation y
>         dist_exp 1
>       }
>     }
>   }
> }
>

Thank you, this is exactly what I was looking for. I did not know the warp
command, that was my problem.

>
> > Another question: I am using a bitmap obtained from a postscript file I
> > have,
> > because I did not find the way to use the PS directly. Is it possible?
> >
>
> No. The valid bitmap types are "gif | tga | iff | ppm | pgm | png | jpeg |
> tiff | sys".
> No vector graphics formats are supported.
>

A pitty. Maybe not many people would use it, I don't know, but for me it would
be useful!

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