Mirrors/servo
1
0
Fork 0
mirror of https://github.com/servo/servo.git synced 2025-08-07 06:25:32 +01:00
Code Issues Projects Releases Packages Wiki Activity

Add average advance width to the font metrics structure, using the X glyph as a best guess.

Browse source
This commit is contained in:
Josh Matthews 2014-09-29 02:15:43 -04:00
parent 08cac68d5a
commit 9b20d6e7d2
3 changed files with 15 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

1
components/gfx/font.rs
View file

@ -78,6 +78,7 @@ pub struct FontMetrics {
pub ascent: Au, pub ascent: Au,
pub descent: Au, pub descent: Au,
pub max_advance: Au, pub max_advance: Au,
pub average_advance: Au,
pub line_gap: Au, pub line_gap: Au,
} }

6
components/gfx/platform/freetype/font.rs
View file

@ -235,6 +235,11 @@ impl FontHandleMethods for FontHandle {
} }
} }
let average_advance = self.glyph_index('x')
.and_then(|idx| self.glyph_h_advance(idx))
.map(|advance| self.font_units_to_au(advance))
.unwrap_or(max_advance_width);
let metrics = FontMetrics { let metrics = FontMetrics {
underline_size: underline_size, underline_size: underline_size,
underline_offset: underline_offset, underline_offset: underline_offset,
@ -246,6 +251,7 @@ impl FontHandleMethods for FontHandle {
ascent: ascent, ascent: ascent,
descent: -descent, // linux font's seem to use the opposite sign from mac descent: -descent, // linux font's seem to use the opposite sign from mac
max_advance: max_advance, max_advance: max_advance,
average_advance: average_advance,
line_gap: height, line_gap: height,
}; };

9
components/gfx/platform/macos/font.rs
View file

@ -153,6 +153,12 @@ impl FontHandleMethods for FontHandle {
let scale = px_to_pt(self.ctfont.pt_size() as f64) / (ascent + descent); let scale = px_to_pt(self.ctfont.pt_size() as f64) / (ascent + descent);
let line_gap = (ascent + descent + leading + 0.5).floor(); let line_gap = (ascent + descent + leading + 0.5).floor();
let max_advance_width = Au::from_pt(bounding_rect.size.width as f64);
let average_advance = self.glyph_index('x')
.and_then(|idx| self.glyph_h_advance(idx))
.map(|advance| Au::from_frac_px(advance))
.unwrap_or(max_advance_width);
let metrics = FontMetrics { let metrics = FontMetrics {
underline_size: Au::from_pt(self.ctfont.underline_thickness() as f64), underline_size: Au::from_pt(self.ctfont.underline_thickness() as f64),
// TODO(Issue #201): underline metrics are not reliable. Have to pull out of font table // TODO(Issue #201): underline metrics are not reliable. Have to pull out of font table
@ -168,7 +174,8 @@ impl FontHandleMethods for FontHandle {
em_size: em_size, em_size: em_size,
ascent: Au::from_pt(ascent * scale), ascent: Au::from_pt(ascent * scale),
descent: Au::from_pt(descent * scale), descent: Au::from_pt(descent * scale),
max_advance: Au::from_pt(bounding_rect.size.width as f64), max_advance: max_advance_width,
average_advance: average_advance,
line_gap: Au::from_frac_px(line_gap), line_gap: Au::from_frac_px(line_gap),
}; };
debug!("Font metrics (@{:f} pt): {:?}", self.ctfont.pt_size() as f64, metrics); debug!("Font metrics (@{:f} pt): {:?}", self.ctfont.pt_size() as f64, metrics);