[arabic] Use glyph advance width in apply_stch() instead of extents

That seems to be what Windows is doing, and makes more sense.
This commit is contained in:
Behdad Esfahbod 2015-12-17 11:04:33 +00:00
parent f11c11a1f1
commit 86bcbd65b0

View File

@ -463,10 +463,6 @@ apply_stch (const hb_ot_shape_plan_t *plan,
* Second pass applies the stretch, copying things to the end of buffer.
*/
/* 30 = 2048 / 70.
* https://www.microsoft.com/typography/cursivescriptguidelines.mspx */
hb_position_t overlap = font->x_scale / 30;
DEBUG_MSG (ARABIC, NULL, "overlap for stretching is %d", overlap);
int sign = font->x_scale < 0 ? -1 : +1;
unsigned int extra_glyphs_needed = 0; // Set during MEASURE, used during CUT
typedef enum { MEASURE, CUT } step_t;
@ -504,18 +500,15 @@ apply_stch (const hb_ot_shape_plan_t *plan,
hb_in_range<unsigned> (info[i - 1].arabic_shaping_action(), STCH_FIXED, STCH_REPEATING))
{
i--;
hb_glyph_extents_t extents;
if (!font->get_glyph_extents (info[i].codepoint, &extents))
extents.width = 0;
extents.width -= overlap;
hb_position_t width = font->get_glyph_h_advance (info[i].codepoint);
if (info[i].arabic_shaping_action() == STCH_FIXED)
{
w_fixed += extents.width;
w_fixed += width;
n_fixed++;
}
else
{
w_repeating += extents.width;
w_repeating += width;
n_repeating++;
}
}
@ -540,7 +533,7 @@ apply_stch (const hb_ot_shape_plan_t *plan,
/* Number of additional times to repeat each repeating tile. */
int n_copies = 0;
hb_position_t w_remaining = w_total - w_fixed - overlap;
hb_position_t w_remaining = w_total - w_fixed;
if (sign * w_remaining > sign * w_repeating && sign * w_repeating > 0)
n_copies = (sign * w_remaining) / (sign * w_repeating) - 1;
@ -562,13 +555,10 @@ apply_stch (const hb_ot_shape_plan_t *plan,
}
else
{
hb_position_t x_offset = -overlap;
hb_position_t x_offset = 0;
for (unsigned int k = end; k > start; k--)
{
hb_glyph_extents_t extents;
if (!font->get_glyph_extents (info[k - 1].codepoint, &extents))
extents.width = 0;
extents.width -= overlap;
hb_position_t width = font->get_glyph_h_advance (info[k - 1].codepoint);
unsigned int repeat = 1;
if (info[k - 1].arabic_shaping_action() == STCH_REPEATING)
@ -578,7 +568,7 @@ apply_stch (const hb_ot_shape_plan_t *plan,
repeat, info[k - 1].codepoint, j);
for (unsigned int n = 0; n < repeat; n++)
{
x_offset -= extents.width;
x_offset -= width;
if (n > 0)
x_offset += extra_repeat_overlap;
pos[k - 1].x_offset = x_offset;