> I am attempting to create a pane of glass that refracts light as though it were
> a prism.
>
> Consider this attempt that didn't work.
>
> object{
>    box{<10,1/2,10>, -<10,1/2,10> }
>    texture{T_Glass3}
>    interior{ ior 1.5 dispersion 2.4 dispersion_samples 150  caustics 0.4 }
>    normal{function{0.1*z}}
>    photons{target refraction on reflection on}
> }
>
> I have tried many different settings and the problem seems to be in the normal
> statement.
>
> I want the stars on the other side of the glass to be dispersed along the z
> direction similar to this attempt http://goo.gl/i2gfS
>
> This is the closest I have gotten, using bumps in the normal statement
> http://goo.gl/OfEIq
>
> I want the faces of the pane of glass to behave as if they are pointed in a
> specific direction.... how do i do this?
>
>

The problem with your solution is that the same normal affect both faces 
of your box.
Change it as follow:

difference{
   box{<10,1/2,10>, -<10,0,10> }
   box{<10.1, 0.4,10.1><-10.1, 0.1, -10.1> pigment{rgbt 1} 
normal{function{0.1*z}}}
   pigment{rgbt 1}// Fully transparent pigment.
   interior{ ior 1.5 dispersion 2.4 dispersion_samples 150  caustics 0.4 }
   photons{target refraction on reflection on}
}

This way, one face of your box have a normal while the other don't.
I replaced the glass texture to a plain rgbt 1 pigment. We don't need 
the added highlights and reflection here.

This is not the way I'd do that.

I'd make an actual thin rism with your actual interior.

prism{4 20 <10,0><-10,-0.5><-10,0.5><10,0>
     pigment{rgbt 1}
     interior{ ior 1.5 dispersion 2.4 dispersion_samples 150}
     photons{target refraction on reflection on}
     translate -10*y
     rotate <90,90,0>
    }


it on the X-Z plane.

Reverse that rotation to have it point toward +Z.

Anyway, you should NOT use caustics in this case. It's ok to simulate 
the caustics on a pool's bottom, it's realy poor in any other situation.



Alain

Post a reply to this message