Marlin renderer patches for jdk8u integration

[Laurent Bourgès]

Hi David,

Thanks for testing the Marlin renderer patches, it looks quite good.

Sorry for my late response, I expected to test myself on a windows machine,
but still not.

I wonder why the 1px difference on windows awt widgets has not been yet
reported.
Phil or Sergey, are you aware of such issue ? How are awt widgets rendered
? How can the java2d renderer interfere in such way ?
Is it related to fractional scaling factors ?

I will try using awt/2d debug settings to get more details...

Laurent

Le ven. 8 nov. 2019 à 02:32, David Alvarez <alvdavi at amazon.com> a écrit :

> Hi,
>
> We’ve run the TCK with Marlin enabled, certification passes. So far so
> good.
>
> Then, in some of our additional testing we noticed small differences in
> the rendering of some components.
>
> The simplest example we’ve been able to find is the java.awt.Choice in
> Windows 10. When using a JDK with the patches applied, this component
> will be rendered with one extra height pixel.
>
> I've uploaded some images for comparison. Here[1] is how the component
> is displayed using 8u232, and here[2], how it looks when using a version
> of 8u232 that contains your patches. The difference is noticeable when
> we put the components side by side[3], more so if we zoom in[4].
>
> This can also cause a one-pixel overlap when these components are
> rendered on a vertical box layout[5].
>
> The behavior persisted even when changing the rendering engine back to
> Pisces, so it seems it is caused by changes outside Marlin, most likely
> on AAShapePipeline.
>
> The new behavior is consistent with JDK11, but it still worries me a
> little. Any idea why this is happening? If you want, I can provide you
> with a sample program and compared images.
>
> For reference, I've also updated the code used during the images[6]
>
> --
> David Alvarez
>
> [1] http://cr.openjdk.java.net/~alvdavi/emails/marlin/vanilla.png
> [2] http://cr.openjdk.java.net/~alvdavi/emails/marlin/marlin.png
> [3] http://cr.openjdk.java.net/~alvdavi/emails/marlin/comparison.png
> [4] http://cr.openjdk.java.net/~alvdavi/emails/marlin/detail.png
> [5] http://cr.openjdk.java.net/~alvdavi/emails/marlin/multiple.png
> [6] http://cr.openjdk.java.net/~alvdavi/emails/marlin/MarlinTest.java
>
>
>
> On 2019-11-05 02:40, Laurent Bourgès wrote:
> > Hi Paul
> >
> > Le lun. 4 nov. 2019 à 20:30, Hohensee, Paul <hohensee at amazon.com
> > <mailto:hohensee at amazon.com>> a écrit :
> >
> >     Also, we (Amazon) would like the Marlin renderer enabled by default,
> >     just as it is for Zulu. It's been well-tested starting in 9, plus I
> >     doubt it'll get much, if any, use in u242 if we e.g. disable it for
> >     u242 and then enable it for u252.
> >
> >     Please put the patches on cr.openjdk.java.net
> >     <http://cr.openjdk.java.net> so we can go through a normal review
> >     process.
> >
> >
> > I uploaded all patch files (m01 to m21):
> > http://cr.openjdk.java.net/~lbourges/marlin-jdk8/marlin-jdk8.0/
> >
> > Laurent
>
>