documentation on QMLSceneGraph internals

[Marco Martin]

On Tuesday 03 September 2013, Marco Martin wrote:
> that is also another of the many advantages of using standardized
> components and sticking with it: for instance we have clip enabled only on
> PlasmaExtras.ScrollArea and that's it (and plasmoids should normally never
> have to touch that, we have to ensure tough that default plasmoids are
> written with a certain amount of discipline)
> 
> what i am more concerned about, that may be worth benchmarking and
> optimizing is limiting as much as possible the number of objects created,
> having in qml as less elements declared as possible and having as much as
> possible created on demand only when needed, that will impact a lot on
> both startup time and memory usage, real and perceived

on this, i made and experiment, now in the window-list plasmoid:
it uses a ConditionalLoader to wrap most of the ui, so that it gets actually 
created only the first time the popup is actually opened.

It's pretty noticeable the difference in startup time (and the fact that the 
memory usage goes up when a popup is opened for the first time and only the 
first time)

since the "average" case will have quite some popupapplets in the panel 
(mostly in the systray) that may take hours before the user opens them, if at 
all

the downside is that isn't exactly intuitive how is written: has quite some 
boilerplate and easy to get wrong...
we could either try to make it more automagic (but will always require some 
level of understanding) or just make it right the most used applets in a 
default setup, that would already give quite an edge in the average use case

-- 
Marco Martin