mirrors/emacs
1
Fork 0
mirror of git://git.sv.gnu.org/emacs.git synced 2026-01-01 09:51:22 -08:00
Code Issues Projects Releases Wiki Activity

Consistently round glyph advances in the SFNT font backend

Browse source 
* src/sfnt.h (SFNT_ROUND_FIXED): New macro.

* src/sfntfont.c (sfntfont_get_glyph_outline): Don't apply
advance width distortion before the glyph is instructed or
decomposed.  Round advance width as measured between both
phantom points subsequent to instruction code execution.
(sfntfont_draw): Don't take the advance's ceiling when advancing
origin point.
This commit is contained in:
Po Lu 2023-12-26 14:07:58 +08:00
parent a6ef458e38
commit cd91ecedcb
2 changed files with 12 additions and 7 deletions
Download patch file Download diff file Expand all files Collapse all files

1
src/sfnt.h
View file

@ -1455,6 +1455,7 @@ struct sfnt_post_table
#define SFNT_CEIL_FIXED(fixed) (((fixed) + 0177777) & 037777600000)
#define SFNT_ROUND_FIXED(fixed) (((fixed) + 0100000) & 037777600000)
#define SFNT_FLOOR_FIXED(fixed) ((fixed) & 037777600000)

18
src/sfntfont.c
View file

@ -2257,9 +2257,6 @@ sfntfont_get_glyph_outline (sfnt_glyph glyph_code,
head, maxp))
goto fail;
/* Add the advance width distortion. */
temp.advance += distortion.advance;
if (interpreter)
{
if (glyph->simple)
@ -2295,8 +2292,11 @@ sfntfont_get_glyph_outline (sfnt_glyph glyph_code,
if (outline)
{
/* Save the new advance width. */
temp.advance = advance;
/* Save the new advance width. This advance width is
rounded again, as the instruction code executed might
have moved both phantom points such that they no
longer measure a fractional distance. */
temp.advance = SFNT_ROUND_FIXED (advance);
/* Finally, adjust the left side bearing of the glyph
metrics by the origin point of the outline, should a
@ -2319,6 +2319,11 @@ sfntfont_get_glyph_outline (sfnt_glyph glyph_code,
sfntfont_get_metrics,
&dcontext);
/* Add the advance width distortion, which is not applied to
glyph metrics in advance of their being instructed, and thus
has to be applied before the metrics are. */
temp.advance += distortion.advance;
/* At this point, the glyph metrics are unscaled. Scale them
up. If INTERPRETER is set, use the scale placed within. */
sfnt_scale_metrics (&temp, scale);
@ -2328,7 +2333,6 @@ sfntfont_get_glyph_outline (sfnt_glyph glyph_code,
been applied by either instruction code or glyph variation.
The left side bearing is the distance from the origin point
to the left most point on the X axis. */
if (index != -1)
temp.lbearing = outline->xmin - outline->origin;
}
@ -3707,7 +3711,7 @@ sfntfont_draw (struct glyph_string *s, int from, int to,
if (s->padding_p)
current_x += 1;
else
current_x += SFNT_CEIL_FIXED (metrics.advance) / 65536;
current_x += metrics.advance / 65536;
}
/* Call the window system function to put the glyphs to the