Questions about "presentation:background-visible"

[Regina Henschel <regina.henschel@libreoffice.org>]

Hi all,

I try to solve some layer and background bugs for LibreOffice. Thereby I 
have come across attributes "20.224 
presentation:background-objects-visible" and "20.225 
presentation:background-visible". But the specification leaves some 
questions unanswered.

1
The attributes belong to the <style:drawing-page-properties> element. 
Such can be child of a <style:style> element or <style:default-style> 
element of family "drawing-page". And that can be referenced from a 
<draw:page> and from a <style:master-page> element by the 
draw:style-name attribute.

Are the attributes "background-objects-visible" and "background-visible" 
usable with ordinary pages and with master-pages as well?


2
The attributes have the prefix "presentation". Does that mean, that they 
are only applicable in a presentation document?



The description in section 20.224 is e.g. "false: objects in background 
of a master page should not be displayed when displaying a presentation 
page." and in 20.225 e.g "false: background of a master page should not 
be displayed when displaying a presentation page"

3
What situations are covered by "displaying a presentation page"?
Edit mode of a page/slide
Show mode of a slide
Printing of a page/slide
Export to a different format like PDF or PNG
Thumbnails used e.g. in Handout, Notes pages, Slide sorter

4
Is "a presentation page" intended as restriction ? (see question 2)

5
Why "should not" ?

6
What is "background of a master page"?  I thought a master page _is_ a 
common background for drawing pages. And if I take the filling given in 
<style:page-layout-properties> element or in the 
<style:drawing-page-properties> element as "background", then the 
wording "objects in background of a master page" makes no sense. Perhaps 
"objects of a master page"?

7
16.9 <style:master-page> lists a lot of child elements. Which are 
considered to be "objects" that are hidden by the 
"background-objects-visible" attribute?

8
There exists other means to specify visibility, e.g. the draw:display 
attribute of a <draw:layer> element, or draw:fill="none" and 
draw:opacity="0%", or presentation:display-footer or similar attributes. 
How does this interact with "background-visible" and 
"background-objects-visible"?

Kind regards
Regina