<i18n dev> Problems drawing supplemental characters in Java.

[Phil Race]

Sounds like https://bugs.openjdk.java.net/browse/JDK-8015556
[macosx] surrogate pairs do not render properly (show up as boxes or 
incorrect glyphs)

But that was fixed in 7u40. What JDK 7 update is in use here ?

-phil.

On 4/9/14 9:17 AM, Naoto Sato wrote:
> Hi Mark,
>
> On 4/9/14, 3:11 AM, Mark Davis ☕️ wrote:
>> I'm having some trouble with drawing supplemental characters in Java. It
>> appears to be due to bugs in Java.
>>
>> *First, how do I report this? And second, can anyone think of a
>> work-around?*
>
> Here is the link to report an issue against JDK:
>
> http://bugreport.java.com/bugreport/
>
> Please choose "classes_2d" as the subcategory.
>
>>
>> This is on a Mac OS 10.9.2, JDK 7, and I am rendering a number of
>> characters in a loop.
>>
>> When I call
>>
>>                  graphics.drawString(s, xStart, ascent);
>>
>> Each supplemental character that shares the same first char (high
>> surrogate) gets the same image (see attachments).
>>
>> It appears that it is caching by char instead of by code point.
>>
>>
>> To work around the problem, I tried changing the code to draw glyph
>> vectors instead.
>>
>>                  FontRenderContext frc = 
>> graphics.getFontRenderContext();
>>
>>                  GlyphVector gv = myFont.createGlyphVector(frc, s);
>>
>>                  ...
>>
>>                  Shape shape = gv.getOutline(xStart, ascent);
>>
>>                  graphics.draw(shape);
>>
>> To my surprise, it got even worse: I get an unknown glyph after each
>> image. See attachments.
>>
>> It appears that when it is advancing through the string to get the
>> glyphs, it is picking up the glyph ID for the code point, but then it is
>> only advancing by 1, so it is always picking up garbage after each
>> character.
>
> Yeah, your explanation does sound like what's happening in the font 
> rendering on MacOSX. Phil/Mike, do you have any idea what's going on?
>
> Naoto