Warp wrote:
> Bryan Heit <bjh### [at] nospamucalgaryca> wrote:
>> If I had to guess, povray probably assigns integer values (i.e. 
>> x = 4 units, y = 3 units) when you use the default aspect ratio, but 
>> stores the decimal values (i.e. x = 1.33333 units, y = 1 unit) when you 
>> enter the aspect ratio manually.
> 
>   That can't be. POV-Ray calculates the result of "4/3" before it does
> anything with that value.
> 

It was a guess on my part, but I think I wasn't clear in my description. 
    There is a difference in the bmp headers if you add "right x*(4/3)" 
to the camera code vs the "default" header you get when you don't 
declare "right".  The difference appears to be in the part of the BMP 
header which sets the physical size of the file.  Without a proper 
header reader I cannot tell exactly what is going on.

What I suspect is going on is that povray may enter the x&y size of the 
image to be 4 and 3 when the right statement is not added to the camera 
  (BMP's don't store aspect ratios, but rather store the x and y size of 
the picture in units of length [mm, cm, or something]).  But I suspect 
that when you enter the "right" code into the camera povray calculates 
the 1.333, and enters that as the physical side (i.e. x=1.333, y=1). 
Either should give the proper aspect ratio, but as I mentioned, the 
older version of the software I was using did not read the default 
povray aspect ratio properly.

The main thing here is that it was my software, not povray, making the 
mistake.  Long story short - if you're going to use virtualdub to 
convert your bmp's to avi's, make sure you get a version newer then 1.1.

Bryan

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