[OS X TeX] How to split horizontally the PDF preview in TeXshop

[Vincent Verfaille]

On 8-Oct-09, at 9:25 AM, Herbert Schulz wrote:
> I'm a bit confused by your description. I'd think a ``horizontal  
> split'' would put the panes above each other, etc. In any case, If  
> you want to see two adjacent pages at once does Preview->Display  
> Format->Double Page or Double MultiPage do what you want?

Oups... I've always been confused about what is horizontal ;-)
(confusion between the fact that the window is split in 2 shorter  
vertical segments, with a horizontal line between the two that you can  
move to resize the 2 segments).

So I mean vertical split, where the window has a vertical bar to split  
between left and right, in order to display 2 different and NON  
successive pages (as for the other already implement split, with the  
rightmost button).
For instance, when editing section III of a document (1 page is  
displayed on the left) and using some previously given information in  
section I (displayed on the right).
Any hints?

I remember somone asked a similar question question, on another list,  
but could not find the message anymore.
He said something like "I finally edited the nib files", which may  
mean he was able to do it by hacking the sources, which I am not able  
to.

Best,

Vincent