Re: [OpenJDK 2D-Dev] RFR: 8217731: Font rendering and glyph spacing changed from jdk-8 to jdk-11

2019-06-05 Thread Philip Race




On 6/5/19, 4:18 PM, Semyon Sadetsky wrote:

On 6/5/19 2:11 PM, Phil Race wrote:


It *can* make a difference and in fact we have a regression test
that now passes with this fix which tests different rendering modes.

Which test is it? Why  you didn't mark it with the bug id?


See https://bugs.openjdk.java.net/browse/JDK-8199529

I only located this bug and verified this "resolves" it after sending 
out the review
but it "resolves" it due to luck as much as anything definite, so I 
don't think it is

required to link this as "solving" that.


However that is not a direct test for this potential difference.
You cannot say that this change *must* make a difference, it
just does. Sometimes.


That's what we need to avoid regression again when fonts are updated. 
Font appearance directly affects user experience. Fortunately this 
happens not so often but we definitely need a test that will indicate 
such changes before the bug is reported externally like it recently 
happened. I thin everyone agrees that we should not repeat this 
omission once again.


You misunderstand. There was no regression. There was a change in behaviour
which is completely allowable, and can happen all the time and is 
sensitive to

so many things. So there was no omission. Nothing can be tested and asserted
to be right or wrong. And the algorithms used are outside of our control.
But there is still value in the change to see if more people are happy 
with the

alternative rendering.


-phil





--Semyon



-phil.

On 6/5/19 1:40 PM, semyon.sadet...@oracle.com wrote:

Can you clarify does the change affects font metrics?

I see that it is a sub-pixel difference for each single glyph but if 
a long line of text can accumulate a notable difference the reg test 
can be provided.


--Semyon

On 6/5/19 11:43 AM, Phil Race wrote:

bug: https://bugs.openjdk.java.net/browse/JDK-8217731
webrev: http://cr.openjdk.java.net/~prr/8217731/

This is intended to "help" but cannot completely cure, with
some of the rendering differences in JDK11 vs JDK 8.
In a typical Swing app on Windows using LCD rendering
it manifests as subtle adjustments in the spacing between glyphs.
There isn't an easy regression test for this, and it is subjective
as to how bad it was before and how much this improves it,
even if you were to accept that 8 is "better" .. and not just 
different ..


-phil.






Re: [OpenJDK 2D-Dev] RFR: 8217731: Font rendering and glyph spacing changed from jdk-8 to jdk-11

2019-06-05 Thread Semyon Sadetsky

On 6/5/19 2:11 PM, Phil Race wrote:


It *can* make a difference and in fact we have a regression test
that now passes with this fix which tests different rendering modes.

Which test is it? Why  you didn't mark it with the bug id?

However that is not a direct test for this potential difference.
You cannot say that this change *must* make a difference, it
just does. Sometimes.


That's what we need to avoid regression again when fonts are updated. 
Font appearance directly affects user experience. Fortunately this 
happens not so often but we definitely need a test that will indicate 
such changes before the bug is reported externally like it recently 
happened. I thin everyone agrees that we should not repeat this omission 
once again.


--Semyon



-phil.

On 6/5/19 1:40 PM, semyon.sadet...@oracle.com wrote:

Can you clarify does the change affects font metrics?

I see that it is a sub-pixel difference for each single glyph but if 
a long line of text can accumulate a notable difference the reg test 
can be provided.


--Semyon

On 6/5/19 11:43 AM, Phil Race wrote:

bug: https://bugs.openjdk.java.net/browse/JDK-8217731
webrev: http://cr.openjdk.java.net/~prr/8217731/

This is intended to "help" but cannot completely cure, with
some of the rendering differences in JDK11 vs JDK 8.
In a typical Swing app on Windows using LCD rendering
it manifests as subtle adjustments in the spacing between glyphs.
There isn't an easy regression test for this, and it is subjective
as to how bad it was before and how much this improves it,
even if you were to accept that 8 is "better" .. and not just 
different ..


-phil.






Re: [OpenJDK 2D-Dev] RFR: 8217731: Font rendering and glyph spacing changed from jdk-8 to jdk-11

2019-06-05 Thread Phil Race

It *can* make a difference and in fact we have a regression test
that now passes with this fix which tests different rendering modes.
However that is not a direct test for this potential difference.
You cannot say that this change *must* make a difference, it
just does. Sometimes.

-phil.

On 6/5/19 1:40 PM, semyon.sadet...@oracle.com wrote:

Can you clarify does the change affects font metrics?

I see that it is a sub-pixel difference for each single glyph but if a 
long line of text can accumulate a notable difference the reg test can 
be provided.


--Semyon

On 6/5/19 11:43 AM, Phil Race wrote:

bug: https://bugs.openjdk.java.net/browse/JDK-8217731
webrev: http://cr.openjdk.java.net/~prr/8217731/

This is intended to "help" but cannot completely cure, with
some of the rendering differences in JDK11 vs JDK 8.
In a typical Swing app on Windows using LCD rendering
it manifests as subtle adjustments in the spacing between glyphs.
There isn't an easy regression test for this, and it is subjective
as to how bad it was before and how much this improves it,
even if you were to accept that 8 is "better" .. and not just 
different ..


-phil.






Re: [OpenJDK 2D-Dev] RFR: 8217731: Font rendering and glyph spacing changed from jdk-8 to jdk-11

2019-06-05 Thread semyon . sadetsky

Can you clarify does the change affects font metrics?

I see that it is a sub-pixel difference for each single glyph but if a 
long line of text can accumulate a notable difference the reg test can 
be provided.


--Semyon

On 6/5/19 11:43 AM, Phil Race wrote:

bug: https://bugs.openjdk.java.net/browse/JDK-8217731
webrev: http://cr.openjdk.java.net/~prr/8217731/

This is intended to "help" but cannot completely cure, with
some of the rendering differences in JDK11 vs JDK 8.
In a typical Swing app on Windows using LCD rendering
it manifests as subtle adjustments in the spacing between glyphs.
There isn't an easy regression test for this, and it is subjective
as to how bad it was before and how much this improves it,
even if you were to accept that 8 is "better" .. and not just 
different ..


-phil.




[OpenJDK 2D-Dev] RFR: 8217731: Font rendering and glyph spacing changed from jdk-8 to jdk-11

2019-06-05 Thread Phil Race

bug: https://bugs.openjdk.java.net/browse/JDK-8217731
webrev: http://cr.openjdk.java.net/~prr/8217731/

This is intended to "help" but cannot completely cure, with
some of the rendering differences in JDK11 vs JDK 8.
In a typical Swing app on Windows using LCD rendering
it manifests as subtle adjustments in the spacing between glyphs.
There isn't an easy regression test for this, and it is subjective
as to how bad it was before and how much this improves it,
even if you were to accept that 8 is "better" .. and not just different ..

-phil.