diff options
| author | Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@nokia.com> | 2011-03-15 09:39:13 +0100 |
|---|---|---|
| committer | Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@nokia.com> | 2011-03-15 10:21:11 +0100 |
| commit | 6d4ef0ff8fd30e5f50f6f770d651a51584e5cfdc (patch) | |
| tree | 8613625828bb40cc178b0101f915304bea818d93 /src/gui/text/qfontenginedirectwrite.cpp | |
| parent | 3c20b3ed8e89e351f1fb459e6ff5439f30958141 (diff) | |
Fix grayscale antialiasing with DirectWrite engine
The code that converted DirectWrite's output to grayscale in
alphaMapForGlyph() had a bunch of copy-paste errors and had obviously
not been tested properly. We invert the input to the gamma function to
get the right curve and then invert the output back. See windows
font engine for comparison.
Reviewed-by: Jiang Jiang
Diffstat (limited to 'src/gui/text/qfontenginedirectwrite.cpp')
| -rw-r--r-- | src/gui/text/qfontenginedirectwrite.cpp | 7 |
1 files changed, 1 insertions, 6 deletions
diff --git a/src/gui/text/qfontenginedirectwrite.cpp b/src/gui/text/qfontenginedirectwrite.cpp index 23fff0d740..af5bab2ffe 100644 --- a/src/gui/text/qfontenginedirectwrite.cpp +++ b/src/gui/text/qfontenginedirectwrite.cpp @@ -485,12 +485,7 @@ QImage QFontEngineDirectWrite::alphaMapForGlyph(glyph_t glyph, QFixed subPixelPo uint *src = (uint*) im.scanLine(y); uchar *dst = indexed.scanLine(y); for (int x=0; x<im.width(); ++x) { - *dst = qGray(*src); - if (QNativeImage::systemFormat() == QImage::Format_RGB16) - *dst = 255 - qGray(*src); - else - *dst = 255 - (qt_pow_gamma[qGray(*src)] * 255. / 2047.); - + *dst = 255 - (qt_pow_gamma[qGray(0xffffffff - *src)] * 255. / 2047.); ++dst; ++src; } |