RFR: 8377937: [macos] GlyphMetrics advance does not consider font rotation

[Phil Race]

On Sat, 14 Feb 2026 16:13:27 GMT, Daniel Gredler <dgredler at openjdk.org> wrote:

> On macOS, `GlyphMetrics` advance provides only the x-component of the advance, not the y-component. This is usually not an issue, since most text does not have any y-component advance. However, if the font is rotated, this does cause problems.
> 
> This bug was discovered during fixing of the manual test `java/awt/print/PrinterJob/PrintTextTest.java` (this test is intended to test printing, but this bug was actually causing the `GlyphVector`s on page 8 to be drawn incorrectly on screen, not just on paper).
> 
> `FileFontStrike.getGlyphMetrics( )` was helpful as a guide regarding the expected behavior of `CStrike.getGlyphMetrics( )`.
> 
> Tested on mac, Linux and Windows:
> - make test TEST="jtreg:test/jdk/java/awt/font"
> - make test TEST="jtreg:test/jdk/java/awt/Graphics2D/DrawString"

@prsadhuk we need a 2nd reviewer here.

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PR Comment: https://git.openjdk.org/jdk/pull/29726#issuecomment-3938133098