Hi everybody !

	I'm posting here a message I've sent to Nathan himself
about 10 days ago, but for which I had no answer... Maybe it's
just that this problem is not so important ;-) Anyway here it
is, slightly modified though:


I'm updating a conversion tool (devoted to scientific visualization)
to add a MegaPOV support using the mesh2 object, where triangles
have a different color (texture) at each vertex. Unfortunately, when
transforming the object in space (rotation/translation...), the
textures are not transformed as well, sometimes leading to a completely
invisible object. Of course, applying the same transformation to every
textures definitions does not correct the thing...

Here is an example (derived from the demos):


//      Persistence of Vision Ray Tracer Scene Description File
//      File: smooth_color_triangle.pov
//      Date: 15/11/99
//      Demo showing a triangle with different colors at each vertex.
        
#version unofficial MegaPov 0.5;

camera {
        location <0.0, 0.5, -4>
        angle 30
        look_at <0.0, 0.0, 0.0>
}

light_source {
        <30, 30, -100>
        color rgb <1.0, 1.0, 1.0> 
}
light_source { <0.0, 0.0, -50> rgb 0.3 }

mesh2 {
 vertex_vectors { 3,
<-0.8,-0.5,0.0>,<0.0,0.5,0.0>,<0.8,-0.5,0.0>
 }
 normal_vectors { 3,
<0.0,0.0,-1>,<0.0,0.0,-1>,<0.0,0.0,-1>
 }
 texture_list { 3,
texture{pigment{rgb<1,0,0>}},
texture{pigment{rgb<0,1,0>}},
texture{pigment{rgb<0,0,1>}}
 }
 face_indices{ 1,
<0,1,2>,0,1,2
 }
// rotate z*90  // uncomment to see the difference
// translate x  // or this one
}


Added in this post:
The problem seems to be the same for triangles using a texture_list.

I hope this will be fixed soon, as MegaPOV offers an interesting answer
to memory requirements of such objects... especially if this will be
part of the next POV-Ray 3.5 !

Thanks Nathan =)


*** Nicolas Calimet
*** http://altern.org/pov4grasp

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