POV-Ray : Newsgroups : povray.general : Can't rotate texture? : Re: Can't rotate texture? Server Time
4 Nov 2024 16:09:24 EST (-0500)
  Re: Can't rotate texture?  
From: Vincent LE CHEVALIER
Date: 24 May 2004 06:05:54
Message: <40b1c902$1@news.povray.org>
gonzo wrote:
> I created a texture to put lighter edges on an object using the slope
> pattern. Applied the texture at the origin, but when I rotate the object
> into position the texture doesn't rotate with it. Can't create the texture
> already rotated because I will have many instances of the object in
> different positions.
> 
> Is this normal behavior for slope pattern?  I thought that once applied a
> texture transforms with the object, no?
> 

I think the slope pattern is indeed rotated, but it does not produce the 
effect you expected. No matter the transform applied to it, slope always 
compute the value returned with the dot product of the object's normal 
and the direction specified. The problem is that the slope's direction 
vector does not get transformed. And thus the color repartition after 
the transformation does change. This is what is needed most of the time, 
when you use slope to mimic a layer deposed on the object, such as snow 
on heightfield,...
Even if you rotate the texture at its creation, the results will be the 
same.
The only way I can think of, to get the effect you want, would be to 
turn your whole texture statement into a macro, with the direction of 
the slope as an argument. Then for each object, you could pass a 
different direction to this macro, depending on the object's transform.
I have not tested it though, so I cannot assure you it works fine...

Hope this will help

-- 
Vincent


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