Graphics2D.drawPolyline performance on JDK 8 vs. JDK 11 (repost)

[Peter Hull]

Thanks Kevin and Dalibor.
I've filed a Java bug (first time for everything!)
and will post to 2d-dev also.
Pete

On Tue, 9 Oct 2018 at 12:09 Kevin Rushforth <kevin.rushforth at oracle.com>
wrote:

> I suggest posting this on the 2d-dev at openjdk.java.net mailing list.
>
> -- Kevin
>
> On 10/9/2018 2:00 AM, Peter Hull wrote:
> > I've recently started using Java 11 and noticed that drawPolyline is
> > much slower on my PC than it was on Java 8.
> > Example, simplified code:
> >      @Override
> >      protected void paintComponent(Graphics g) {
> >          super.paintComponent(g);
> >          Graphics2D graphics = (Graphics2D) g;
> >          long starttime = System.nanoTime();
> >          graphics.drawPolyline(xs, ys, xs.length);
> >          long endtime = System.nanoTime();
> >          Logger.getLogger(this.getClass().getName()).log(Level.INFO,
> > "Paint Time: {0}s", (double)(endtime-starttime) / 1.0e9);
> >      }
> > where xs[] and ys[] are large (65536 points) integer arrays. On
> > OpenJDK8_x64_Win_jdk8u172-b11 I get a paint time of 0.025s and on
> > openjdk-11+28_windows-x64 it is 25s, i.e. factor of 1000.
> > This may be related to JEP263 (HiDPI)
> >
> > I've got a recent Core i7 processor with Intel graphics, running Windows
> 10.
> >
> > Is this a bug do you think and if so, where to report it?
> >
> > Thanks,
> > Peter
>
>