| commit | 58b477d1581f715d75c2e117ffa9489c6e64a678 | |
| author | Zhiyi Zhang <zzhang@codeweavers.com> | |
| Fri, 12 Aug 2022 03:32:54 +0000 (12 11:32 +0800) | ||
| committer | Alexandre Julliard <julliard@winehq.org> | |
| Fri, 19 Aug 2022 20:45:18 +0000 (19 22:45 +0200) | ||
| tree | c261ee3225c392135ffd5bcb6de0ecf15099558c | treesnapshot (tar.gz zip) |
| parent | 821b36e00bd99924a454bf2e982fe7d4924f08e7 | commitdiff |
win32u: Choose a smaller ppem to avoid exceeding the requested font height.
When height > 0, CreateFontA/W() should not return a font face exceeding the requested height.
For instance, Tahoma has 2049 units of ascent, 423 units of descent and its units per EM square is
2048. When requesting a font 20 pixels in height, ppem = units_per_EM * requested_height / (ascent + descent)
= 2048 * 20 / (2049 + 423) = 16.57 ~= 17. When getting the resulting height back from the ppem,
resulting_height = (ascent + descent) * ppem / units_per_EM = (2049.0 + 423) * 17 / 2048 = 20.52
~=21. So it ends up getting a larger font than requested and violates the spec.
Fix Nancy Drew: Legend of the Crystal Skull crash at start.
Signed-off-by: Zhiyi Zhang <zzhang@codeweavers.com>
When height > 0, CreateFontA/W() should not return a font face exceeding the requested height.
For instance, Tahoma has 2049 units of ascent, 423 units of descent and its units per EM square is
2048. When requesting a font 20 pixels in height, ppem = units_per_EM * requested_height / (ascent + descent)
= 2048 * 20 / (2049 + 423) = 16.57 ~= 17. When getting the resulting height back from the ppem,
resulting_height = (ascent + descent) * ppem / units_per_EM = (2049.0 + 423) * 17 / 2048 = 20.52
~=21. So it ends up getting a larger font than requested and violates the spec.
Fix Nancy Drew: Legend of the Crystal Skull crash at start.
Signed-off-by: Zhiyi Zhang <zzhang@codeweavers.com>
| dlls/gdi32/tests/font.c | diffblobblamehistory | |
| dlls/win32u/freetype.c | diffblobblamehistory |