[OS X TeX] texshop and preview

[Herbert Schulz]

On Oct 9, 2009, at 10:16 AM, Doris Wagner wrote:

>
>> Howdy,
> also howdy,
>>
>> TeXShop doesn't use Preview to display the pdf but it's own pdf  
>> display which uses the same PDFKit framework as Preview.
>
> oh! I didn't know this! what is a PDFKit framework? what exactly is  
> the difference between the two Previews then? ...

Howdy,

I'm not much of a programmer but let me take a stab at this. The  
PDFKit framework is a large group of underlying, relatively high level  
functions (and objects) supplied by Apple that provides the ability to  
display, search, etc., pdf files. It makes it relatively easy to  
implement a pdf viewer within an application. E.g., Mail.app can  
easily display pdf files from within the application. Preview.app is a  
standalone application that uses PDFKit to display pdf files (plus  
lots of other stuff). Another fairly popular stand alone viewer that  
uses PDFKit is Skim.

The advantage is that when you write a new application you don't have  
to re-invent the wheel every time. The disadvantage is that a bug in  
PDFKit will then show up in any application that uses that framework.  
There have been several bugs in PDFKit that were discovered by TeX  
folk and even a bug in several TeX programs and fonts that were  
exposed by PDFKit.

Good Luck,

Herb Schulz
(herbs at wideopenwest dot com)