On Wed, 9 Nov 2022 18:30:26 GMT, Kevin Rushforth <k...@openjdk.org> wrote:
>> tests/system/src/test/java/test/robot/javafx/scene/PixelBufferDrawTest.java
>> line 189:
>>
>>> 187:
>>> 188: private void compareColor(Color exp, Color act) {
>>> 189: Assert.assertEquals(exp.getRed(), act.getRed(), 0.01);
>>
>> I am curious: what is the source of these differences?
>> Is it color model (and could we explicitly set the CM?)
>> Or is it differences in anti-aliasing or some such?
>
> It's a good question, but I note that any number of things can cause such
> differences on some systems. As I mentioned in the bug report, most of our
> robot-based tests use `0.07` as a tolerance value. The idea being that these
> tests aren't trying to check whether the rendering is pixel perfect or that
> the shaders, etc., produce an exact value. They are just checking whether the
> pixel is red versus green versus orange, etc.
I decided to do a bit more digging and I found out that those tests pass with
original 0.005 tolerance if you plug in an external display and make it your
main. In short:
* Plugged in a 1080p display via HDMI port
* Made the 1080p display the main display
* To be sure tests will execute on it I mirrored 1080p display contents onto
built-in Retina XDR display (I couldn't find an option to disable it).
As a result, these tests started to pass again. Hard to say why exactly that
happens, could be HiDPI-related, could be no HDR on my 1080p display, could be
something else... Regardless, higher tolerance in these tests should still be
okay as Kevin mentioned.
-------------
PR: https://git.openjdk.org/jfx/pull/944
