RFR: 8207379: Robot screen capture test fails with HiDPI at some screen locations [v2]

[Kevin Rushforth]

On Fri, 15 Mar 2024 11:37:53 GMT, Karthik P K <kpk at openjdk.org> wrote:

>> Lukasz Kostyra has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   Fix cast formatting
>
> Tested the changes in Mac, Windows and Linux. The changes fixes the issues in Mac and Windows.
> I ran the test in Linux VM and it failed with and without the fix with error:
> 
> RobotTest > testScreenCapture FAILED
>     junit.framework.AssertionFailedError: expected: rgba(255,0,255,255) but was: rgba(0,0,0,255)
>         at test.robot.javafx.scene.RobotTest.assertColorEquals(RobotTest.java:848)
>         at test.robot.javafx.scene.RobotTest.testScreenCapture(RobotTest.java:774)
> 
> 
> Changing the scale also did not make any difference. Not sure if it is related to anything in VM.
> It is a Ubuntu 22.04 VM
> 
> Added a minor comment inline.

> @karthikpandelu I just tried this on Ubuntu 22.04 VM and everything seems to work fine. (0,0,0,255) returned from capture suggests capture failed - could it be your VM is running on Wayland instead of X11?

I also just ran this, and it runs fine for me on an Ubuntu 22.04 VM. Since Wayland is the default in 22.04, I also suspect that Karthik was running in that mode. You can check the value of the `XDG_SESSION_TYPE` env var to see. All robot tests that read the screen will fail on Wayland until [JDK-8326712](https://bugs.openjdk.org/browse/JDK-8326712) is fixed (should be done reasonably soon, sometime in the JavaFX 23 time frame).

-------------

PR Comment: https://git.openjdk.org/jfx/pull/1403#issuecomment-2008178337