organicmaps/harfbuzz
13
Fork 0
mirror of https://github.com/harfbuzz/harfbuzz.git synced 2025-04-14 09:10:48 +00:00
Code Issues 1 Projects Releases Wiki Activity Actions

[ot-math] Fix a bug in MathKern::get_value()

Browse source 
Fixes https://github.com/harfbuzz/harfbuzz/issues/4542
This commit is contained in:
Lie Yan 2024-01-07 22:10:10 +08:00 • committed by GitHub
parent 5852d328a4
commit c17d67467f
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
2 changed files with 10 additions and 12 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

14
src/hb-ot-math-table.hh
View file

@ -344,13 +344,11 @@ struct MathKern
const MathValueRecord* kernValue = mathValueRecordsZ.arrayZ + heightCount;
int sign = font->y_scale < 0 ? -1 : +1;
/* The description of the MathKern table is a ambiguous, but interpreting
* "between the two heights found at those indexes" for 0 < i < len as
*
* correctionHeight[i-1] < correction_height <= correctionHeight[i]
*
* makes the result consistent with the limit cases and we can just use the
* binary search algorithm of std::upper_bound:
/* According to OpenType spec (v1.9), except for the boundary cases, the index
* chosen for kern value should be i such that
* correctionHeight[i-1] <= correction_height < correctionHeight[i]
* We can just use the binary search algorithm of std::upper_bound(), which
* matches the spec, including for the boundary cases.
*/
unsigned int i = 0;
unsigned int count = heightCount;
@ -358,7 +356,7 @@ struct MathKern
{
unsigned int half = count / 2;
hb_position_t height = correctionHeight[i + half].get_y_value (font, this);
if (sign * height < sign * correction_height)
if (sign * height <= sign * correction_height)
{
i += half + 1;
count -= half + 1;

8
test/api/test-ot-math.c
View file

@ -313,12 +313,12 @@ test_get_glyph_kerning (void)
g_assert(hb_font_get_glyph_from_name (hb_font, "I", -1, &glyph));
g_assert_cmpint(hb_ot_math_get_glyph_kerning (hb_font, glyph, HB_OT_MATH_KERN_TOP_RIGHT, 7), ==, 62); // lower than min height
g_assert_cmpint(hb_ot_math_get_glyph_kerning (hb_font, glyph, HB_OT_MATH_KERN_TOP_RIGHT, 14), ==, 62); // equal to min height
g_assert_cmpint(hb_ot_math_get_glyph_kerning (hb_font, glyph, HB_OT_MATH_KERN_TOP_RIGHT, 14), ==, 104); // equal to min height
g_assert_cmpint(hb_ot_math_get_glyph_kerning (hb_font, glyph, HB_OT_MATH_KERN_TOP_RIGHT, 20), ==, 104);
g_assert_cmpint(hb_ot_math_get_glyph_kerning (hb_font, glyph, HB_OT_MATH_KERN_TOP_RIGHT, 23), ==, 104);
g_assert_cmpint(hb_ot_math_get_glyph_kerning (hb_font, glyph, HB_OT_MATH_KERN_TOP_RIGHT, 23), ==, 146);
g_assert_cmpint(hb_ot_math_get_glyph_kerning (hb_font, glyph, HB_OT_MATH_KERN_TOP_RIGHT, 31), ==, 146);
g_assert_cmpint(hb_ot_math_get_glyph_kerning (hb_font, glyph, HB_OT_MATH_KERN_TOP_RIGHT, 32), ==, 146);
g_assert_cmpint(hb_ot_math_get_glyph_kerning (hb_font, glyph, HB_OT_MATH_KERN_TOP_RIGHT, 86), ==, 398); // equal to max height
g_assert_cmpint(hb_ot_math_get_glyph_kerning (hb_font, glyph, HB_OT_MATH_KERN_TOP_RIGHT, 32), ==, 188);
g_assert_cmpint(hb_ot_math_get_glyph_kerning (hb_font, glyph, HB_OT_MATH_KERN_TOP_RIGHT, 86), ==, 440); // equal to max height
g_assert_cmpint(hb_ot_math_get_glyph_kerning (hb_font, glyph, HB_OT_MATH_KERN_TOP_RIGHT, 91), ==, 440); // larger than max height
g_assert_cmpint(hb_ot_math_get_glyph_kerning (hb_font, glyph, HB_OT_MATH_KERN_TOP_RIGHT, 96), ==, 440); // larger than max height