On Thu, 17 Aug 2023 20:55:29 GMT, Phil Race <p...@openjdk.org> wrote:
>> **Problem** >> >> Glyphs aren't stretched by applying an affine transform `scale(2, 1)` to a >> font. Instead, the space between glyphs increases. >> >> **Root Cause** >> >> Bitmaps embedded in the font are used to render the glyphs; the bitmaps >> aren't transformed, so white-space is seen which fills the requested >> horizontal size. >> >> **Fix** >> >> Disable using embedded bitmaps if horizontal transform is different from the >> vertical one. >> >> It's similar to [JDK-8204929](https://bugs.openjdk.org/browse/JDK-8204929) >> and [JDK-8255387](https://bugs.openjdk.org/browse/JDK-8255387). >> >> **Test** >> >> When embedded bitmaps are used, the right half of the image remains filled >> with the background colour. The test looks for non-white pixels in the right >> half of the image. If there are only white pixels in the right half of the >> image, the test fails; if there are other colours, the test passes. >> >> I can reproduce the problem on Windows only. Without the fix, the test >> reports 6 failures for "MS Gothic", "MS PGothic" and "MS UI Gothic" fonts >> when text antialiasing is off and when LCD antialiasing is enabled. If >> greyscale antialiasing is enabled, the glyphs are stretched as expected, >> this case was handled in JDK-8204929; it can be used as a workaround. >> >> All client tests pass. >> >> The test could be *headless*, but headless systems, especially with Linux, >> don't have fonts installed. Without fonts, the test is useless, therefore I >> made it *headful*. > > test/jdk/java/awt/font/FontScaling/StretchedFontTest.java line 50: > >> 48: /* >> 49: * @test >> 50: * @key headful > > I don't see anything in this test that requires headful. Ah, I see you wrote "The test could be headless, but headless systems, especially with Linux, don't have fonts installed. Without fonts, the test is useless, therefore I made it headful." In fact they should. We already require this. And it really would be just Linux that's an issue and FWIW I doubt you'll find CJK fonts with embedded bitmaps on Linux anyway. Microsoft are the only OS vendor that make much use of them. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/15335#discussion_r1297763085
