Re: [office] Re: [xml-dev] A few questions about the file format.

[Michael Brauer <michael.brauer@sun.com>]

Hi David,

David Faure wrote:
> (Forwarding on oasis a rather old discussion I started on xml-dev with Daniel)
> 
> 
>>>>3.10.8/9/11  What is the difference between fo:font-family and style:font-name?
>>
>>The style:font-name attribute refers to a <style:font-decl>.
>>
>>Basically, the font-decl mechanism adds a level f indirection so you 
>>don't have to write the same information (font-family, font-pitch, etc.) 
>>over and over again. You _can_ supply that information in the style 
>>directly, but you can also ccollect it in the font-decl, and then refer 
>>to it using style:font-name.
> 
>  
> And style:font-style-name is a similar indirection, but which points to
> a character style defined by the user, right?

The name of many fonts as they are installed on a certain system does 
not only consist of the font family name (like "Arial" or "Times"), but 
also includes attributes like "Black", "Bold" or "Italic". The 
"style:font-style-name" attribute can contain such attribute names and 
can be used to improve the font matching of an application that in most 
cases only knows the family name.

However, the CSS2/SVG font-face declaration has the same purpose but 
offers more powerfull font description. So I suggest we adopt it and 
leave the "style:font-style-name" in the specification only for 
compatibility reasons.


>  
> 
>>>>3.10.4    What is style:use-window-font-color? I can't make sense of the description.
>>
>>When people change background colors (e.g. to highlight something, or 
>>for artistic reasons), they usually want their text to remain readable. 
>>To support this, we support an 'automatic' text color (this is what the 
>>UI calls it): On dark background this is white, and on a light 
>>background this is some default color. This is encoded by the 
>>style:use-window-font-color attribute. It's the OOo default behaviour 
>>for text color.
> 
> 
> Seems very difficult for another application to implement this, if the choice
> of the color (depending on the bg color) isn't better specified. I suggest that
> the actual algorithm to determine the text color from the bg color be part
> of the file format documentation...
> 

The style:use-window-font-color specifies that the document window's 
text color should be used. It can be specified either by the operating 
system or the office application, but it is not document specific and 
can vary from system to system. Since this can result in unreadable 
documents if the font and the background color both are very dark or 
very light, black is used on very light background colors and dark on 
very bright colors. Ony may include the actual algorithm for this, but 
I'm not sure whether this is realy required, because there will be no 
guarentee that a certain color is used anyway, and whatever color is 
used, it is correct.

Best regards

Michael