Questions about family=graphic versus family=presentation

[David Faure <faure@kde.org>]

Hello,

Here are some questions about the OASIS spec, from the maintainer of 
the KOffice presentation application, KPresenter.
(In quoted text: extracts from the spec, in reply to those: his questions)

======

> 9.2.15 Common Drawing Shape Attributes
>
> Style
>
> The draw:style-name and presentation:style-name attributes specify a style  
> for the drawing shape. If draw:style-name is used, the shape is a regular 
> graphic shape. If presentation:style-name is used, the shape is a
> presentation shape as described in section 9.6.
>
> The value of both attributes is the name of a <style:style> element. If 
> the draw:style-name attribute is used, the style must have a family value of
> graphic. If the presentation:style-name is used, the style must have a
> family value of presentation. The formatting properties of the specified
> style and its optional parent styles are used to format the shape. See 
> also section 14.13.1. 

As far as I understand this, both styles can used. The use family presentation 
is described in 9.6.

> The draw:class-names and presentation:class-names attributes take a
> whitespace separated list of either graphic or presentation style names. The
> referenced styles are applied in the order they are contained in the list.
> If both, draw:style-name and draw:class-names, or both
> presentation:style-name and presentation:class-names are present, the style 
> referenced by the style-name attribute is treated as the first style in the
> list in the class-names attribute. Conforming application should support the
> class-names attribute and also should preserve it while editing.
>
> 9.6 Presentation Shapes
>
> Presentation shapes are special text box, image, object or thumbnail drawing
> shapes contained in a presentation. Presentation shapes use styles with a
> style family value of presentation, unlike drawing shapes which use styles
> with a style family value of graphic. Presentation shapes can be empty,
> acting only as placeholders. 

Is this only true if empty or are all presentation shapes placeholders? If 
they are placeholders would that mean that is what we call templates (e.g. 
empty textboxes the user can fill, so you can have e.g. title and on text 
field or title and two columns).

> If a draw page's presentation layout (see
> section 14.15) is changed, all presentation shapes are adapted 
automatically.
> Standard drawing shapes can also be used in presentations. The 
presentation:class
> attribute distinguishes presentation shapes from drawing shapes. Unlike 
presentation shapes,
> standard drawing shapes are not adapted if the presentation page layout is 
changed.

This also describes the use of family presentation as placeholders.

>
> 9.6.1 Common Presentation Shape Attributes
>
> The attributes described in this section are common to all presentation
> shapes. 
>
> Style
>
> Presentation shapes can have styles from the style family presentation
> assigned to them. A presentation shape can be distinguished from a drawing
> shape by checking whether it has a presentation:style-name attribute. A
> drawing shape uses a draw:style-name attribute with a style from the graphic
> family, while a presentation shape uses a presentation:style-name attribute
> with a style from the presentation family. This name links to a
> <style:style> element with the family presentation. The formatting
> properties in this style and its optional parent styles are used to format
> this shape. See also section 9.2.15. 
>
> Class
>
> The presentation:class attribute classifies presentation shapes by their
> usage within a draw page (for instance as title or outline). The following
> classes are existing: 
>
> • title: Titles are standard text shapes.
> • outline: Outlines are standard text shapes.
> • subtitle: Subtitles are standard text shapes.
> • text: Presentation texts are standard text shapes.
> • graphic: Presentation graphics are standard graphic shapes
> • object: Presentation objects are standard object shapes.
> • chart: Presentation charts are standard object shapes.
> • table: Presentation tables are standard object shapes.
> • orgchart: Presentation organization charts are standard object shapes.
> • page: Presentation pages are used on notes pages.
> • notes: Presentation notes are used on notes pages.
> • handout: Presentation handouts are placeholder for the drawing page in an
> handout page. 
>
> The next four classes can be used only for drawing shapes that are contained
> in master pages. Depending on the settings of the page (see section 15.36),
> they are displayed automatically on drawing pages that use the master page.
>
> • header: The drawing shape is used as a header. Header shapes are standard
> text shapes. 
> • footer: The drawing shape is used as a footer. Footer shapes are standard
> text shapes. 
> • date-time: The drawing shape is used as a date and/or time shape. Date and
> Time shapes are standard text shapes.
> • page-number: The drawing shape is used as a page number shape. Page Number
> shapes are standard text shapes.
>
> 14.13 Graphic Styles
>
> 14.13.1 Graphic and Presentation Styles
>
> Graphic and presentation styles are <style:style> elements that have either
> the family graphic or presentation. Graphic styles with family graphic may
> occur within all kinds of applications, graphic styles with family
> presentation may occur only within presentation documents. Both kind of
> styles support the graphic properties described in section 15.17. They may
> also contain paragraph and text properties as described in sections 15.5
> and .  
>
> 14.15 Presentation Page Layouts
>
> The element <style:presentation-page-layout> is a container for
> placeholders, which define a set of empty presentation objects, for example,
> a title or outline. These placeholders are used as templates for creating
> new presentation objects and to mark the size and position of an object if
> the presentation page layout of a drawing page is changed. 
> The <style:presentation-page-layout> element has an attribute style:name. It
> defines the name of the page layout. If a drawing page has been created
> using a presentation page layout, the name of the layout is contained in the
> draw page's presentation:presentation-page-layout-name attribute. The
> optional style:display-name attribute specifies the name of the presentation
> page layout as it should appear in the user interface.
>
> 14.15.1 Presentation Placeholder
>
> The element <presentation:placeholder> specifies a placeholder for
> presentation objects for example, a title or outline.
> The element has the following attributes:
> • object: Specifies the kind of object the element is a placeholder for. The
> value equals the of the presentation:class attribute for presentation 
> shapes. See section 9.6. 
> • svg:x, svg:y, svg:width, svg:height: position and size attributes as
> specified in section 9.2.15, with the exception that percentage values are
> allowed for placeholders. 

I have seen that oo-impress uses family presentation for all objects generated 
on the masterpages. If all objects in family presentation are placeholders 
I'm not sure if this is correct.Should placeholders be shown in a 
presentation. In oo e.g. rect objects are shown but some textboxes are not. 
How do I distinguish between both?

One strange thing I noticed about oo-impress is that it uses family 
presentation forobjects created on the master page. If you now copy this 
object to a normal page it has still this property. If an object is generated 
on the normal page it has uses the family graphic. If this object is copied 
to a master page it keeps this property.

This might be a bug in oo :-).

Questions: 
1. What is the use of objects in family presentation?
2. For which objects should family presentation be used?
3. Are placeholders objects to be used as templates?
4. Are objects on a masterpage family presentation?

Here is my opinion on what the standard says. I might be totally wrong here.
1. They are used for placeholder objects like title or outline the customer 
can fill up when is creating his presentation (templates).
2. Only placeholder objects, this makes sense for text objects, but I don't 
know how a placeholder rect or other objects could be used.
3. Yes.
4. No.

I'm not sure if I described this good enough, so if I was not clear enough 
please ask and I try to specify it more clearly.

Have a nice day,

Thorsten Zachmann <t.zachmann@zagge.de>

======

-- 
David Faure, faure@kde.org, sponsored by Trolltech to work on KDE,
Konqueror (http://www.konqueror.org), and KOffice (http://www.koffice.org).