Bad character spacing (kerning?) in Linux

[Arne Augenstein]

Thanks Phil, I think you've put me on the right track. I'm using 
Manjaro, which is a very close derivative of Archlinux. Looking at 
https://wiki.archlinux.org/index.php/font_configuration#Subpixel_rendering 
it seems this really could be the underlying problem. Subpixel 
rendering is disabled by default on Archlinux systems.

I probably will need a few days to verify that this is in fact the 
issue. I will report back as soon as I've found out more.

Arne

On Mi, Mär 7, 2018 at 6:10 PM, Phil Race <philip.race at oracle.com> 
wrote:
> The Linux image shows greyscale text.
> The Mac image shows subpixel LCD text.
> The latter can be positioned with sub-pixel (1/3 pixel) resolution.
> 
> Why does this make a difference ?
> JavaFX like  CoreText + DirectWrite, and unlike GDI + Swing uses 
> unhinted glyphs
> with floating point accumulation of the positions.
> But the raster problem is that you need to align the glyph to 
> discrete pixels
> 
> In the subpixel case you have 3x the resolution to play with and the 
> rounding to
> the raster grid is not obvious.
> 
> If your linux system were configured to support LCD subpixel text I'd 
> expect
> it to be similar to Mac .. modulo the fact that retina is hi-res and 
> that the fonts will be different.
> 
> So it is probably not something FX has control over .. you need to 
> look at your settings.
> 
> If freetype from your vendor is configured without LCD text support 
> you may be out of luck
> 
> -phil.
> 
> 
> 
> On 03/07/2018 08:51 AM, openjfx at arne-augenstein.de wrote:
>> 
>> Hello all,
>> 
>> I've recently started a project in JavaFX and had some trouble with 
>> inconsistent widths of spaces between characters in Linux. I 
>> haven't been able to find much useful information and therefore 
>> posted a stackoverflow question with a screenshot illustrating the 
>> problem and some simple example code to reproduce the issue. I 
>> think it's better explained with the picture, that's why I won't 
>> repeat myself here and point you instead to my question on that 
>> page:
>> 
>> https://stackoverflow.com/questions/49136131/bad-character-spacing-kerning-in-javafxs-font-rendering-in-linux 
>> 
>> 
>> One of the members of stackoverflow advised me to ask this question 
>> on your mailing list. My question is if this behavior is inherent 
>> to the way JavaFX renders text on Linux. And if there is some 
>> workaround/setting which I could use to circumvent this issue.
>> 
>> Thanks in advance and regards
>> Arne Augenstein
>> 
>