Plasma::Svg and performance

[Jamboarder]

> From: Aaron J. Seigo <aseigo at kde.org>
> one outstanding issue will be clearing the disk and parameter caches when the 
> theme is updated on disk but not changed in the config.
> 
> before i go any further with this approach: any thoughts, ideas, inspirations?
> 
It might be useful in general to scope out all the "persistent stores" of SVG related information and when they need to be cleared/refreshed. As far as I can tell, these "stores" currently include:
- Plasma::Svg QPixmapCache
- Plasma::Svg renderers (the shared svg renderer hash)
- Plasma::PanelSvg QPixmapCache
- this new Plasma::Svg cache(s) for the hint and element parameters.
Are there others?

The events that trigger a clear/refresh include:
themeChanged (if the theme image path is different)
colorsChanged (for svgs that have the apply colors hint)
setImagePath (if the path is different that the current one)

Should a clear/refresh be triggered if the path hasn't changed but the actual file has?  
Are there other events that should trigger a refresh?  
Is it worth consolidating the clearing/refresh of these "persistent stores" in one place (at least for Plasma:Svg)?

Hope this is helpful,
Andrew (Jamboarder) Lake