Setting the FreeType LCD filter

[Phil Race]

I think I can re-open https://bugs.openjdk.java.net/browse/JDK-8188810
The submitter there is comparing windows to Linux so there are many
things that are different, but the fringing in the Linux examples are
enough to make it possible that this was the real issue there.

-phil.


On 09/30/2018 02:03 PM, Philip Race wrote:
> Hi,
>
> Your explanation makes sense.
> Compile time linking is probably best so long as we can verify that
> the function is available on all the platforms we need to build & run 
> on .. notably
> older versions of OEL&RHEL.
>
> Failing that, then as well as adding ".6" we should initialise
>
>     jint rc =-1;
>
> instead of to zero .. so that failure to find the function isn't confused
> as failure *of* the function, which in a nutshell, seems to be the bug 
> here.
> And I suppose we have the same bug on "older" systems where the 
> freetype library is
> found but lack the symbol.
>
> Is there no JBS bug id already open on this ? If one was closed as not 
> reproducible,
> we can re-open it. Better than creating a new one.
>
> -phil.
>
> On 9/30/18, 12:03 PM, John Neffenger wrote:
>> I think I found the cause of the text rendering problem I have always 
>> seen in JavaFX applications on Linux:
>>
>> Reduce color fringes in FreeType subpixel rendering
>> https://github.com/javafxports/openjdk-jfx/issues/229
>>
>> I'm finally seeing the fonts as they were intended! I used the Oracle 
>> bug report outline as a template for the GitHub issue to make it easy 
>> to copy to the Java Bug Database. Do I need a Java Bug ID before I 
>> submit a pull request?
>>
>> Thanks,
>> John
>>
>> P.S.: For background information, there is a great demonstration of 
>> LCD filtering algorithms by Felipe Heidrich at 1:02:47 into the video 
>> "JavaFX Text Rendering" <https://youtu.be/LCrCni6EVek?t=1h2m47s>. The 
>> link takes you directly to the two-minute segment showing the text 
>> rendered by FreeType, first with no filter, and then with its various 
>> filter options. (Note: the audio is a bit loud.)