[wdmmg-dev] Separation of visual styles from data and code

[Gregor Aisch]

Just thought it would be a good idea to join the WDMMG dev list, since I'm currently working on a new visualization for OpenSpendings. So, hello to all :-)

Just talked to Friedrich and Carsten about how to store and maintain visual properties like colours and icons in the future.

By now the colours are defined somewhere inside the database and the flash bubble viz contains some hardcoded icons. In general, I find it a bad idea to store visualization specific properties like colours in the database. Colours, icons and the like are core parts of the visualization (and not the data). A different visualization might want to use different colours and will definitely need a different set of icons than the ones used in the bubble chart.

So what we need is a clear separation of data, code and visual styles. The data defines the budget items, the visual style defines how the items will look like and the code renders the items in a certain way. Some visual properties like colours might be re-used across different visualizations, others must be defined each time we introduce a new visualization or classification. Of course we can use fallbacks like random colours or default icons to reduce the amount of work a bit. In case of hierarchical classifications inheritance of visual properties might also be a good idea.

We will develop a proposal for the visual style format while working on the new bubble charts. I think a JSON dict is a good starting point.

Any comments?

Gregor
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.okfn.org/pipermail/openspending-dev/attachments/20110428/08249987/attachment.html>