Alain <aze### [at] qwertyorg> wrote:
> Stone1 is the closest to your intended result.
> You may need to change your light's position to get optimum result.
> Your camera may not be located correctly.
> Any gem have an ior, diamond's ior is close to 2.5.
> A gem also have variable reflection. That reflection follows the fresnel
> model.
> There are some specular highlights.
> You need some environment. It can be as simple or complicated as you want.
> You may need to adjust max_trace_level. 5 is probably way to small.
> Some times, you want to see the light_source... it looks_like{...}
> Very low to zero ambient and low diffuse value.
> Try to add some dispersion. Stay just a little over 1.
> Take a look at glass.inc to get some ideas.
> When things are looking good, please use anti aliasing.
>
>
> Alain

Here is the texture and material that I am using for all of the triangles and
the mesh (material for mesh, texture for triangles).
#declare Diamond_Tex = texture
{
  pigment { rgbf <1, 1, 1, 1> }

  finish
  {
    ambient 0
    diffuse 0
    brilliance 0.5
    specular 0.9
    roughness 0.05

    reflection
    {
      colour rgb <1, 1, 1>
      0.1
      fresnel on
    }

    conserve_energy
  }
}

#declare Diamond_Mat = material
{
  texture { Diamond_Tex }

  interior
  {
    ior 2.417
    caustics 1
    dispersion Diamond_Dispersion     // Defined in consts.inc
    dispersion_samples 7
    fade_power 2                      // Used because POV-Ray complained about
me using refraction in the finish, said I should use fade_power and
fade_distance instead.
    fade_distance 1
    fade_colour colour White
  }
}

I added a sphere of radius 5 centered at the origin as an evironment (just added
it) to no effect, I still get the same results as I did. I coloured it white. If
I use rgb <1, 1, 1> with a radius of 10 everything vomes up grey, with a radius
of 5 the whole screen is a complete white-wash, using rgbf/t<1, 1, 1, 1> gives
me the same results as Stone1.bmp (both with a radius of 5 or 10). If I specify
no colour the whole picture is black (can't see the gem at all). Am I doing the
right thing here for an environment?

I had already changed max_trace_level from 5 to 10 (was getting warnings about
it, 10 removed the warnings). However I further changed it to 50 and then 100,
the only change that made was that the top of the gem got brigther and at 100 it
was nearly completely white.

I ran through all the finishes and interioirs in glass.inc. All the finishes
gave results close to that of Stone3.bmp, so i kept my finish. All the interiors
gave little to no change to the one I already had.

One thing that I am noticing is that it spends a lot of time rendering the top
of the gem (the part with the most clarity in Stone1.bmp) and then it chops
through the last part in less than a second (total rendering time is 17
seconds).

Regards
Bidski

Post a reply to this message