Need an official way to exclude parts of the SceneGraph from CSS-Processing

[Kevin Rushforth]

Improving CSS performance is a big goal for JDK 10. It is very likely 
too late to do anything about this for JDK 9, but Jonathan might be able 
to comment further.

-- Kevin


Tom Schindl wrote:
> Hi,
>
> One of the biggest problems when working with JavaFX is that if you
> reparent a big portion of the SceneGraph is that a full CSS-Pass is
> applied on all reparented SG-Nodes even if those nodes are currently not
> visible (eg. because they are part of a TabPane).
>
> I general I think it is ok to also applyCSS changes on currently not
> visible nodes (eg they still have an influence on layout-bounds) but
> there are situations like the above mentioned example of TabPane that it
> is unnecessary overhead to apply applyCSS changes on those parts of the
> SG until they get visible.
>
> I would not mind if the CSS-Pass on JavaFX would be as performant as the
> one from current browsers but unfortunately it isn't so I'd like to
> discuss the possibility of a API to *temporarily* exclude portions of
> the SG from CSS-Passes.
>
> In JavaFX8 i was able to hack that in by overwriting impl_processCSS in
> a subclass who changed to doProcessCSS who now is private so my hack
> does not work anymore.
>
> To give you an impression on what performance gains we are talking about
> just look at the video I recorded -
> https://tomsondev.bestsolution.at/2016/11/25/improving-minmax-performance-in-e4-on-javafx-applications/
>
> Tom
>
>