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26 Nov 2024 09:18:43 EST (-0500)
  A Question regarding output (Message 1 to 4 of 4)  
From: Anthony D  Baye
Subject: A Question regarding output
Date: 14 Jan 2011 02:40:01
Message: <web.4d2ffd01e15d90971a86e02e0@news.povray.org>
Often I find it more convenient to scale by a single vector component (e.g.
scale 4.0*x)

the problem is that when I go to render, I get massive numbers of parse
warnings, especially if I do this in a loop.

Is it really necessary to warn the user that scale assumes a value of 1 for any
undefined component?

Regards,

A.D.B.


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From: Jim Holsenback
Subject: Re: A Question regarding output
Date: 14 Jan 2011 04:18:20
Message: <4d3014dc$1@news.povray.org>
On 01/14/2011 03:36 AM, Anthony D. Baye wrote:
> Often I find it more convenient to scale by a single vector component (e.g.
> scale 4.0*x)
> 
> the problem is that when I go to render, I get massive numbers of parse
> warnings, especially if I do this in a loop.
> 
> Is it really necessary to warn the user that scale assumes a value of 1 for any
> undefined component?
> 
> Regards,
> 
> A.D.B.
> 
> 
you could turn off the warnings stream:
http://wiki.povray.org/content/Documentation:Reference_Section_1.3#Text_Streams

or a macro:


#macro SFx (SF)
  #local SF = <SF,0,0> + <0,1,1>;
  scale SF
#end

box {<-1,-1,-1>, <1,1,1>
  pigment {rgb <1,0,0>}
  SFx (4)
  }


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From: scott
Subject: Re: A Question regarding output
Date: 14 Jan 2011 04:34:16
Message: <4d301898$1@news.povray.org>
> Is it really necessary to warn the user that scale assumes a value of 1 for any
> undefined component?

What makes you think they are undefined?  4*x means <4,0,0> throughout 
POV (anything else doesn't make sense).  If you don't like using a 
vector for the scale function then you can always set up macros as 
already suggested.


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From: Zeger Knaepen
Subject: Re: A Question regarding output
Date: 14 Jan 2011 05:05:29
Message: <4d301fe9$1@news.povray.org>
On 14/01/2011 8:36, Anthony D. Baye wrote:
> Often I find it more convenient to scale by a single vector component (e.g.
> scale 4.0*x)
>
> the problem is that when I go to render, I get massive numbers of parse
> warnings, especially if I do this in a loop.
>
> Is it really necessary to warn the user that scale assumes a value of 1 for any
> undefined component?

it's not undefined, it's 0.
"scale 4.0*x" is exactly the same as "scale 4.0*<1,0,0>" or "scale 
<4.0,0,0>", so you're actively telling pov-ray to scale it infinitely 
thin in the y- and z-direction. It just assumes you meant to keep the 
dimensions in those directions, but it could just have assumed you 
really meant 0 and scale it as small as computationally possible.

At least, that's how I understand it :)


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