> Hi,
>
> I have a 3D mesh .inc file, including thousands of triangles like this:
>
> }
>    smooth_triangle { // #763945
>      <1.35632e-019, 1.35632e-019, 1.35632e-019>, <0.0147179, 0.999892,
> 0.000199087>,
>      <1.35632e-019, 1.35632e-019, 1.35632e-019>, <0.0147179, 0.999892,
> 0.000199087>,
>      <0.000173748, 1.35632e-019, 3.35076e+012>, <1.93994e-005, 0.992192,
> 0.124723>
>    }
>
>
> , I know what should I expect by rendering it in POV-ray, but somthing strange
> is observed, maybe just 2 or3 triangles.
> Could anybody please show me how I can render a mesh in povray?
> Do I need to use Mesh in the script in povray?
> How I have to decide about the position of camera and light source??
> Thanks!
> Vincent
>
>

The format for a smooth triangle is vertex1, normal1, vertex2, normal2, 
vertex3, normal3.

If the inc file start with mesh{ and have a } at it's end, there should 
be no problem.

Let see, this triangle have 2 identical points making it a degenerate 
triangle. Degenerate triangles are not rendered. If I remenmber 
correctly, 1e-19 is smaller than the epsilon value, whitch is a 
thresshold value to truncate to zero.
Next, you have a point at 3.35e12, whitch is an extremely large value 
(3.35 millions of millions). This can cause the mesh to appear as been 
infinite even if it's not the case, and most of it's triangle degenerate 
and not rendered.

If even one point of a triangle is to far away, it will probably not be 
rendered. Christian proposed scaling your mesh down by 10, 100,... In 
this particular case, you may need to scale down by 1e-7 to 1e-9 to have 
anything... This will make many triangles become sub-pixel in size, even 
if rendered at 16000 by 12000 pixels.

Your range of values going from 1e-19 to 1e12 is extreeme with a 
variation of 31 orders of magnitude. You just can't render such a scene 
without busting the floating point precision limits. Try keeping the 
range of values in your scene within 6 orders of magnitude or less.

Next, when a finite object surround the camera, it often register as 
infinite, as in unboundable. Try rendering this and look at the statistics:
sphere{0, 30 pigment{bozo} finish{ambient 1}}
//no camera so use the default one siting at the origin pointing toward +Z.

Try rendering with +q0 on the command line. This will make all texture 
ambient 1 and turn off any light. It's a good debuging tool and rather 
fast. It will make any part shadowed by other to become visible.





Alain

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