Re: Chart Data Label Positions

[David Faure <faure@kde.org>]

On Monday 20 August 2007, Bjoern Milcke wrote:
> Hi David,
> 
> thanks for your revised proposal.
> 
> > <define name="labelPositions">
> >     <choice>
> >         <value>auto</value>
> >         <value>center</value>
> >         <value>north</value>
> >         <value>north-west</value>
> >         <value>west</value>
> >         <value>south-west</value>
> >         <value>south</value>
> >         <value>south-east</value>
> >         <value>east</value>
> >         <value>north-east</value>
> >         <value>inside</value>
> >         <value>outside</value>
> >         </choice>
> > </define>
> > <define name="style-chart-properties-attlist" combine="interleave">
> >     <optional>
> >         <attribute name="chart:label-position">
> >             <ref name="labelPositions">
> >         </attribute>
> >     </optional>
> > </define>
> >   
> 
> Maybe a good idea to define a separate name for the positions.
You mean the fact that I separated labelPositions into its own define? This was necessary
anyway, for reuse from label-position-negative. I don't like duplicating code :)

> > This attribute defines the position of the labels in the chart.
> > The values inside and outside are only meaningful for pie charts,
> > the other values are only meaningful for other types of charts than pie charts.
> 
> Why have you added this section? inside and outside make also sense for 
> net-charts (radar) and also for bar/column charts. I had some 
> screen-shots of those in my proposal. I would suggest to remove the 
> second sentence of this paragraph.

Agreed.

> I noticed that you dropped "near-origin". What is the suggestion to 
> replace this? Using "south" for positive and "north" for negative values 
> would work for a column chart, but once you switch to bar this would no 
> longer match. I would suggest to re-add "near-origin" again. An implementation can do 
> the same as for (+south,-north) or (+west,-east) depending on the chart 
> type. The advantage of having this additional value is that it is 
> chart-type-independent.
Hmm. This could be said to be a GUI issue rather than a file format issue; 
the file format as I suggest it -can- express the right thing for horizontal bars
by using east and west, so the application could switch from south/north to
west/east when choosing some "near origin" setting in the GUI.

However if you cannot live without it I am ok with re-adding near-origin as long
as it is clearly defined as "a shortcut for +south,-north for vertically-oriented chart types
and for +west,-east for horizontally-oriented chart types). If we make the file format
redundant (two ways to express the same thing) then we must make that redundancy
explicit and define it precisely.

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