Am 08.12.2010 09:40, schrieb scott:

>> If you create a scene using a specific aspect ratio and publish it,
>> then it's not ok anymore.
>
> The problem is though the alternative is also not ok (but in a different
> way). In extreme cases it's obvious, but if someone renders a 1280x1024
> desktop wallpaper at 1600x1200 it might not be obvious things are a
> little distorted. Currently as scene-author you need to decide which
> behaviour you prefer when your scene gets rendered at a different aspect
> ratio (even if you're rendering it yourself, eg for different monitors).

This topic has been discussed over and over and over again - so rather 
than discuss what is the best approach to solve the issue with the tools 
available, I propose to fast-forward the discussion to the point where 
POV-Ray's current toolbox for handling aspect ratio issues is found to 
be incomplete.

See http://bugs.povray.org/task/85 for information on feature proposals 
to mitigate this issue.

For the time being, my personal recommendation for people like me who 
don't want to bother much about aspect ratio is to use the famous 
image_width/image_height approach, irregardless of what that 
equally-famous but somewhat outdated FAQ recommends - because chances 
are they won't be rendering to non-square-pixel targets, nor be too 
outraged if someone happened to render their scene at a "wrong" aspect 
ratio.

For all those who want their scenes to be "aspect-ratio safe", I'd 
suggest to use a simple workaround like:

#define AspectRatio = 4/3;
camera {
   up    y/AspectRatio
   right x
   #if (image_width/image_height <> AspectRatio)
     #warning "Unexpected aspect ratio.\n"
     #error "Comment out this line if you know what you are doing.\n"
   #end
}

And finally, for people who want to be constructive about this issue, 
I'd suggest picking up the glove to write a macro library to help 
dealing with aspect ratio.

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