POV-Ray : Newsgroups : povray.newusers : Re: Noob: Texture rendering as a single color : Noob: Texture rendering as a single color Server Time
30 Jul 2024 04:18:05 EDT (-0400)
  Noob: Texture rendering as a single color  
From: Mike Williams
Date: 22 Oct 2004 04:48:38
Message: <Y6DqgCALkMeBFwOR@econym.demon.co.uk>
Wasn't it Barton Bosch who wrote:
>
>Ok, I'll breach etiqutte and reply to my own post, <g>.  I've been doing
>some serious RtFMing for the last couple of days and I managed to figure
>this one out.
>
>The problem here is that it is impossible to use textures more complex than
>simple colors without a UV map

That is not the case.

I can believe that adding UV mapping solved your problem, but it
certainly is possible to apply complex textures without a UV map.

My first guess would be that somehow you ended up with the "uv_mapping"
keyword in your something_pov.inc file without any "uv_vectors" or
"uv_indices". This would tell POV to use UV mapping but all the points
would be uv_mapped to <0,0>.

My second guess would be that it's a problem of scale. Some 3d programs
tend to work with very large or very small object scales. When PoseRay
converts such files it positions the camera at a distance that
corresponds to the scale. You may not realize that your car is, say,
0.01 pov-units long because your camera is placed 0.03 pov units away
from it. Over such a small scale, the Rusty_Iron texture looks like a
single colour, so you have to apply texture {Rusty_Iron scale 0.01}
See this example of unscaled Rusty_Iron, and then see what happens when
you scale the texture or change the value of R.

global_settings {assumed_gamma 1.0}
light_source {<-30, 100, -300> color rgb 1}
#include "textures.inc"
                         
#declare R=0.01;                         
                         
camera {location -z*R*3 look_at <0,0,0>}
sphere {0,R
  texture {Rusty_Iron scale 1}
}

-- 
Mike Williams
Gentleman of Leisure


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