[prev in list] [next in list] [prev in thread] [next in thread] 

List:       openjdk-openjfx-dev
Subject:    Re: Need an official way to exclude parts of the SceneGraph from CSS-Processing
From:       Tom Schindl <tom.schindl () bestsolution ! at>
Date:       2017-01-24 21:07:43
Message-ID: 036c1f64-be5b-a8b1-e14c-401bd71bc8d7 () bestsolution ! at
[Download RAW message or body]

There you go - https://bugs.openjdk.java.net/browse/JDK-8173301

Tom

On 24.01.17 21:47, Jonathan Giles wrote:
> Tom,
> 
> You can do one better than dream - you can file a JBS issue where we can
> continue to discuss it :-)
> 
> -- Jonathan
> 
> On 24/01/17 10:21 PM, Tom Schindl wrote:
> > Hi Jonathan & Kevin,
> > 
> > Let's take CSS-Performance on the side for a moment.
> > 
> > I think the request I have is in itself already legal because there
> > might be situations where I as a component developer want to rule out
> > CSS-Processing for a complete SG-Area.
> > 
> > It might be performance (as it is in the case I initially mentioned) but
> > I think there are other use cases as well. Let's assume I write a
> > JavaFX-PDF-Viewer (something I really start doing just today) and I want
> > to avoid someone changing any of the SG-Objects I create (even by
> > accident).
> > 
> > A similar problem we see today with the code-editor control we
> > developed, unbound CSS-Rules have a good chance to effect the Text-Nodes
> > who make up our editor and cause performance problems because we have so
> > many Text-Nodes making up the editor!
> > 
> > Today I have no other option than to programmatically setting all sorts
> > of properties because then the CSS-Engine then skips them but this
> > eagerly creates Property-Instances which once more effects memory usage.
> > 
> > I think that I as a control/component developer HAVE TO HAVE the chance
> > to define that the complete SG below me is managed by me and CSS does
> > NOT have to be applied to it.
> > 
> > I would propose the following simple "API":
> > 
> > private boolean cssSensitive = true;
> > 
> > public boolean isCssSensitive() {
> > return cssSensitive;
> > }
> > 
> > public void setCssSensitive(boolean cssSensitive) {
> > if( this.cssSensitive != cssSensitive ) {
> > this.cssSensitive = cssSensitive;
> > if( cssSensitive ) {
> > reapplyCSS(); // or is applyCSS() not sure
> > }
> > }
> > }
> > 
> > private void doProcessCSS() {
> > if( ! cssSensitive ) {
> > return;
> > }
> > }
> > 
> > I do understand that I'm too late in JDK9 cycle to add such an API but
> > one could at least dream about such a thing.
> > 
> > Tom
> > 
> > On 24.01.17 00:15, Jonathan Giles wrote:
> > > There are two different topics here, both of which are near and dear to
> > > my heart (and also make me feel like I've been doing JavaFX for way too
> > > long!).
> > > 
> > > The specific case of TabPane doing CSS / layout on the content of all
> > > tabs is something captured here:
> > > 
> > > https://bugs.openjdk.java.net/browse/JDK-8092206
> > > 
> > > It dates back to 2012 and I remember spending considerable amount of
> > > effort with my team working through this. As can be seen in some of the
> > > comments, there were attempts to improve performance (and they were
> > > really nice), but the outcome was to back it out as we could not change
> > > the default semantics of loading and doing all work on all tabs. The
> > > second-to-last comment was a proposal for some API that would specify
> > > the policy. I really would like to pick this back up for JDK 10, as JDK
> > > 9 is locked and loaded in this regard. I have retargeted this for JDK 10
> > > just now.
> > > 
> > > As Kevin notes, improving performance is a big push I want to get
> > > underway for JDK 10. The more general comment made in your email is -
> > > how can we get better performance out of our critical paths (CSS,
> > > layout, TableView, etc). That's something we will be actively exploring.
> > > There are a lot of ideas, some will yield results and some won't. I've
> > > been running into a few of those dead-ends myself recently as I do
> > > preliminary investigations.
> > > 
> > > If anyone is interested in exploring performance-related topics in
> > > JavaFX, I've got plenty of areas to explore :-) Ping me off-list and we
> > > can discuss.
> > > 
> > > Unfortunately, again, unless there is some critical oversight these
> > > discussions and investigations into performance and additional API are
> > > by default targeted to JDK 10 rather than JDK 9.
> > > 
> > > -- Jonathan
> > > 
> > > On 20/01/17 11:43 PM, 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
> > > > 
> > 
> 


-- 
Thomas Schindl, CTO
BestSolution.at EDV Systemhaus GmbH
Eduard-Bodem-Gasse 5-7, A-6020 Innsbruck
http://www.bestsolution.at/
Reg. Nr. FN 222302s am Firmenbuchgericht Innsbruck


[prev in list] [next in list] [prev in thread] [next in thread]