diff options
author | Eli Zaretskii <eliz@gnu.org> | 2016-05-22 19:20:28 +0300 |
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committer | Eli Zaretskii <eliz@gnu.org> | 2016-05-22 19:20:28 +0300 |
commit | 5ab083034ca221a7b4f00156a0efece84da999d8 (patch) | |
tree | 28c9128c12ce1fbc3df7576044fe2ea38b65fb9f | |
parent | c9f7ec736b78bef5359b6da03296277c535e8e89 (diff) |
Provide workaround for xftfont rendering problem
* src/xftfont.c (syms_of_xftfont) <xft-font-ascent-descent-override>:
New variable.
(xftfont_open): Use it to work around problems with rendering some
fonts. (Bug#23360)
-rw-r--r-- | src/xftfont.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/src/xftfont.c b/src/xftfont.c index 7926325419..34c6f7d3e4 100644 --- a/src/xftfont.c +++ b/src/xftfont.c @@ -395,6 +395,24 @@ xftfont_open (struct frame *f, Lisp_Object entity, int pixel_size) font->ascent = xftfont->ascent; font->descent = xftfont->descent; + /* The following workaround is unnecessary on most systems, and + causes annoying differences in glyph height between regular and + bold fonts (see bug#22383). However, with some fonts, such as + monaco, removing the workaround results in overlapping vertical + space of a line, see bug#23360. As long as the way to reconcile + these opposites is not known, we provide a user option to work + around the problem. */ + if (pixel_size >= 5 + && xft_font_ascent_descent_override) + { + /* The above condition is a dirty workaround because + XftTextExtents8 behaves strangely for some fonts + (e.g. "Dejavu Sans Mono") when pixel_size is less than 5. */ + if (font->ascent < extents.y) + font->ascent = extents.y; + if (font->descent < extents.height - extents.y) + font->descent = extents.height - extents.y; + } font->height = font->ascent + font->descent; if (XINT (AREF (entity, FONT_SIZE_INDEX)) == 0) @@ -733,6 +751,12 @@ syms_of_xftfont (void) DEFSYM (QCembolden, ":embolden"); DEFSYM (QClcdfilter, ":lcdfilter"); + DEFVAR_BOOL ("xft-font-ascent-descent-override", + xft_font_ascent_descent_override, + doc: /* Non-nil means override the ascent and descent values for Xft font driver. +This is needed with some fonts to correct vertical overlap of glyphs. */); + xft_font_ascent_descent_override = 0; + ascii_printable[0] = 0; xftfont_driver = ftfont_driver; |