POV-Ray : Newsgroups : povray.unofficial.patches : Calling all uv experts... : Re: Calling all uv experts... Server Time
2 Sep 2024 18:18:41 EDT (-0400)
  Re: Calling all uv experts...  
From: Cliff Bowman
Date: 24 Aug 1999 21:19:13
Message: <37c342ac.21033067@news.povray.org>
[snip]

>Getting the uv data to map on to the figures is very hard. I've played with
>both rotation( have you tried that Cliff, Both Giles and I found that it was
>necessary to turn the uv map upside down!) and scaling with little success.
>
[snip]

I think I'm probably going to have to switch to the "mesh" syntax
(instead of mesh2). I've tried the following 2 examples, which I think
should look identical - but they don't. They're wildly different here
(with regard to uv mapping):

mesh2
{
  vertex_vectors
   {
    4,
    <-0.5,-0.5,-0.5>,
    <-0.5,0.5,-0.5>,
    <0.5,0.5,-0.5>,
    <0.5,-0.5,-0.5>
  }
  uv_vectors
  {
    4,
    <0,0>,<0,1>,<1,1>,<1,0>
  }
  texture_list
  {
    1,
    texture { OBJuvPOV_Texture },
  }
  face_indices
  {
    2,
    <0, 1, 2>, 0,
    <0, 2, 3>, 0
  }
}

Doesn't appear the same as:

mesh {

	smooth_triangle {
		<-0.5, -0.5, -0.5> <0,0,1> // Normals just faked
		<-0.5, 0.5, -0.5> <0,0,1>  // Normals just faked
		<0.5, 0.5, -0.5> <0,0,1>   // Normals just faked
		uv_vectors
			<0,0>, <0,1>, <1,1>
	}
	smooth_triangle {
		<-0.5, -0.5, -0.5> <0,0,1> // Normals just faked
		<0.5, 0.5, -0.5> <0,0,1>   // Normals just faked
		<0.5, -0.5, -0.5> <0,0,1>  // Normals just faked
		uv_vectors
			<0,0>, <1,1>, <1,0>
	}
	uv_mapping
	texture { OBJuvPOV_Texture }
}


What's more - the second example renders differently in uvPov (alpha
5) than it does in SuperPatch POV. No - really, it does. It renders
*exactly* as I'd hoped they both would...

Methinks if nothing else I've spotted a problem with SuperPatch
POV...?


Cheers,

Cliff Bowman
Why not pay my 3D Dr Who site a visit at http://www.who3d.cwc.net/


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