HarfBuzz text shaping engine
http://harfbuzz.github.io/
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
559 lines
17 KiB
559 lines
17 KiB
/* |
|
* Copyright © 2011,2012 Google, Inc. |
|
* |
|
* This is part of HarfBuzz, a text shaping library. |
|
* |
|
* Permission is hereby granted, without written agreement and without |
|
* license or royalty fees, to use, copy, modify, and distribute this |
|
* software and its documentation for any purpose, provided that the |
|
* above copyright notice and the following two paragraphs appear in |
|
* all copies of this software. |
|
* |
|
* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR |
|
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES |
|
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN |
|
* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH |
|
* DAMAGE. |
|
* |
|
* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, |
|
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND |
|
* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS |
|
* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO |
|
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. |
|
* |
|
* Google Author(s): Behdad Esfahbod |
|
*/ |
|
|
|
#include "hb-ot-shape-fallback-private.hh" |
|
#include "hb-ot-layout-gsubgpos-private.hh" |
|
|
|
static unsigned int |
|
recategorize_combining_class (hb_codepoint_t u, |
|
unsigned int klass) |
|
{ |
|
if (klass >= 200) |
|
return klass; |
|
|
|
/* Thai / Lao need some per-character work. */ |
|
if ((u & ~0xFF) == 0x0E00u) |
|
{ |
|
if (unlikely (klass == 0)) |
|
{ |
|
switch (u) |
|
{ |
|
case 0x0E31u: |
|
case 0x0E34u: |
|
case 0x0E35u: |
|
case 0x0E36u: |
|
case 0x0E37u: |
|
case 0x0E47u: |
|
case 0x0E4Cu: |
|
case 0x0E4Du: |
|
case 0x0E4Eu: |
|
klass = HB_UNICODE_COMBINING_CLASS_ABOVE_RIGHT; |
|
break; |
|
|
|
case 0x0EB1u: |
|
case 0x0EB4u: |
|
case 0x0EB5u: |
|
case 0x0EB6u: |
|
case 0x0EB7u: |
|
case 0x0EBBu: |
|
case 0x0ECCu: |
|
case 0x0ECDu: |
|
klass = HB_UNICODE_COMBINING_CLASS_ABOVE; |
|
break; |
|
|
|
case 0x0EBCu: |
|
klass = HB_UNICODE_COMBINING_CLASS_BELOW; |
|
break; |
|
} |
|
} else { |
|
/* Thai virama is below-right */ |
|
if (u == 0x0E3Au) |
|
klass = HB_UNICODE_COMBINING_CLASS_BELOW_RIGHT; |
|
} |
|
} |
|
|
|
switch (klass) |
|
{ |
|
|
|
/* Hebrew */ |
|
|
|
case HB_MODIFIED_COMBINING_CLASS_CCC10: /* sheva */ |
|
case HB_MODIFIED_COMBINING_CLASS_CCC11: /* hataf segol */ |
|
case HB_MODIFIED_COMBINING_CLASS_CCC12: /* hataf patah */ |
|
case HB_MODIFIED_COMBINING_CLASS_CCC13: /* hataf qamats */ |
|
case HB_MODIFIED_COMBINING_CLASS_CCC14: /* hiriq */ |
|
case HB_MODIFIED_COMBINING_CLASS_CCC15: /* tsere */ |
|
case HB_MODIFIED_COMBINING_CLASS_CCC16: /* segol */ |
|
case HB_MODIFIED_COMBINING_CLASS_CCC17: /* patah */ |
|
case HB_MODIFIED_COMBINING_CLASS_CCC18: /* qamats */ |
|
case HB_MODIFIED_COMBINING_CLASS_CCC20: /* qubuts */ |
|
case HB_MODIFIED_COMBINING_CLASS_CCC22: /* meteg */ |
|
return HB_UNICODE_COMBINING_CLASS_BELOW; |
|
|
|
case HB_MODIFIED_COMBINING_CLASS_CCC23: /* rafe */ |
|
return HB_UNICODE_COMBINING_CLASS_ATTACHED_ABOVE; |
|
|
|
case HB_MODIFIED_COMBINING_CLASS_CCC24: /* shin dot */ |
|
return HB_UNICODE_COMBINING_CLASS_ABOVE_RIGHT; |
|
|
|
case HB_MODIFIED_COMBINING_CLASS_CCC25: /* sin dot */ |
|
case HB_MODIFIED_COMBINING_CLASS_CCC19: /* holam */ |
|
return HB_UNICODE_COMBINING_CLASS_ABOVE_LEFT; |
|
|
|
case HB_MODIFIED_COMBINING_CLASS_CCC26: /* point varika */ |
|
return HB_UNICODE_COMBINING_CLASS_ABOVE; |
|
|
|
case HB_MODIFIED_COMBINING_CLASS_CCC21: /* dagesh */ |
|
break; |
|
|
|
|
|
/* Arabic and Syriac */ |
|
|
|
case HB_MODIFIED_COMBINING_CLASS_CCC27: /* fathatan */ |
|
case HB_MODIFIED_COMBINING_CLASS_CCC28: /* dammatan */ |
|
case HB_MODIFIED_COMBINING_CLASS_CCC30: /* fatha */ |
|
case HB_MODIFIED_COMBINING_CLASS_CCC31: /* damma */ |
|
case HB_MODIFIED_COMBINING_CLASS_CCC33: /* shadda */ |
|
case HB_MODIFIED_COMBINING_CLASS_CCC34: /* sukun */ |
|
case HB_MODIFIED_COMBINING_CLASS_CCC35: /* superscript alef */ |
|
case HB_MODIFIED_COMBINING_CLASS_CCC36: /* superscript alaph */ |
|
return HB_UNICODE_COMBINING_CLASS_ABOVE; |
|
|
|
case HB_MODIFIED_COMBINING_CLASS_CCC29: /* kasratan */ |
|
case HB_MODIFIED_COMBINING_CLASS_CCC32: /* kasra */ |
|
return HB_UNICODE_COMBINING_CLASS_BELOW; |
|
|
|
|
|
/* Thai */ |
|
|
|
case HB_MODIFIED_COMBINING_CLASS_CCC103: /* sara u / sara uu */ |
|
return HB_UNICODE_COMBINING_CLASS_BELOW_RIGHT; |
|
|
|
case HB_MODIFIED_COMBINING_CLASS_CCC107: /* mai */ |
|
return HB_UNICODE_COMBINING_CLASS_ABOVE_RIGHT; |
|
|
|
|
|
/* Lao */ |
|
|
|
case HB_MODIFIED_COMBINING_CLASS_CCC118: /* sign u / sign uu */ |
|
return HB_UNICODE_COMBINING_CLASS_BELOW; |
|
|
|
case HB_MODIFIED_COMBINING_CLASS_CCC122: /* mai */ |
|
return HB_UNICODE_COMBINING_CLASS_ABOVE; |
|
|
|
|
|
/* Tibetan */ |
|
|
|
case HB_MODIFIED_COMBINING_CLASS_CCC129: /* sign aa */ |
|
return HB_UNICODE_COMBINING_CLASS_BELOW; |
|
|
|
case HB_MODIFIED_COMBINING_CLASS_CCC130: /* sign i*/ |
|
return HB_UNICODE_COMBINING_CLASS_ABOVE; |
|
|
|
case HB_MODIFIED_COMBINING_CLASS_CCC132: /* sign u */ |
|
return HB_UNICODE_COMBINING_CLASS_BELOW; |
|
|
|
} |
|
|
|
return klass; |
|
} |
|
|
|
void |
|
_hb_ot_shape_fallback_position_recategorize_marks (const hb_ot_shape_plan_t *plan HB_UNUSED, |
|
hb_font_t *font HB_UNUSED, |
|
hb_buffer_t *buffer) |
|
{ |
|
unsigned int count = buffer->len; |
|
hb_glyph_info_t *info = buffer->info; |
|
for (unsigned int i = 0; i < count; i++) |
|
if (_hb_glyph_info_get_general_category (&info[i]) == HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK) { |
|
unsigned int combining_class = _hb_glyph_info_get_modified_combining_class (&info[i]); |
|
combining_class = recategorize_combining_class (info[i].codepoint, combining_class); |
|
_hb_glyph_info_set_modified_combining_class (&info[i], combining_class); |
|
} |
|
} |
|
|
|
|
|
static void |
|
zero_mark_advances (hb_buffer_t *buffer, |
|
unsigned int start, |
|
unsigned int end) |
|
{ |
|
hb_glyph_info_t *info = buffer->info; |
|
for (unsigned int i = start; i < end; i++) |
|
if (_hb_glyph_info_get_general_category (&info[i]) == HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK) |
|
{ |
|
buffer->pos[i].x_advance = 0; |
|
buffer->pos[i].y_advance = 0; |
|
} |
|
} |
|
|
|
static inline void |
|
position_mark (const hb_ot_shape_plan_t *plan, |
|
hb_font_t *font, |
|
hb_buffer_t *buffer, |
|
hb_glyph_extents_t &base_extents, |
|
unsigned int i, |
|
unsigned int combining_class) |
|
{ |
|
hb_glyph_extents_t mark_extents; |
|
if (!font->get_glyph_extents (buffer->info[i].codepoint, &mark_extents)) |
|
return; |
|
|
|
hb_position_t y_gap = font->y_scale / 16; |
|
|
|
hb_glyph_position_t &pos = buffer->pos[i]; |
|
pos.x_offset = pos.y_offset = 0; |
|
|
|
|
|
/* We don't position LEFT and RIGHT marks. */ |
|
|
|
/* X positioning */ |
|
switch (combining_class) |
|
{ |
|
case HB_UNICODE_COMBINING_CLASS_DOUBLE_BELOW: |
|
case HB_UNICODE_COMBINING_CLASS_DOUBLE_ABOVE: |
|
if (buffer->props.direction == HB_DIRECTION_LTR) { |
|
pos.x_offset += base_extents.x_bearing + base_extents.width - mark_extents.width / 2 - mark_extents.x_bearing; |
|
break; |
|
} else if (buffer->props.direction == HB_DIRECTION_RTL) { |
|
pos.x_offset += base_extents.x_bearing - mark_extents.width / 2 - mark_extents.x_bearing; |
|
break; |
|
} |
|
HB_FALLTHROUGH; |
|
|
|
default: |
|
case HB_UNICODE_COMBINING_CLASS_ATTACHED_BELOW: |
|
case HB_UNICODE_COMBINING_CLASS_ATTACHED_ABOVE: |
|
case HB_UNICODE_COMBINING_CLASS_BELOW: |
|
case HB_UNICODE_COMBINING_CLASS_ABOVE: |
|
/* Center align. */ |
|
pos.x_offset += base_extents.x_bearing + (base_extents.width - mark_extents.width) / 2 - mark_extents.x_bearing; |
|
break; |
|
|
|
case HB_UNICODE_COMBINING_CLASS_ATTACHED_BELOW_LEFT: |
|
case HB_UNICODE_COMBINING_CLASS_BELOW_LEFT: |
|
case HB_UNICODE_COMBINING_CLASS_ABOVE_LEFT: |
|
/* Left align. */ |
|
pos.x_offset += base_extents.x_bearing - mark_extents.x_bearing; |
|
break; |
|
|
|
case HB_UNICODE_COMBINING_CLASS_ATTACHED_ABOVE_RIGHT: |
|
case HB_UNICODE_COMBINING_CLASS_BELOW_RIGHT: |
|
case HB_UNICODE_COMBINING_CLASS_ABOVE_RIGHT: |
|
/* Right align. */ |
|
pos.x_offset += base_extents.x_bearing + base_extents.width - mark_extents.width - mark_extents.x_bearing; |
|
break; |
|
} |
|
|
|
/* Y positioning */ |
|
switch (combining_class) |
|
{ |
|
case HB_UNICODE_COMBINING_CLASS_DOUBLE_BELOW: |
|
case HB_UNICODE_COMBINING_CLASS_BELOW_LEFT: |
|
case HB_UNICODE_COMBINING_CLASS_BELOW: |
|
case HB_UNICODE_COMBINING_CLASS_BELOW_RIGHT: |
|
/* Add gap, fall-through. */ |
|
base_extents.height -= y_gap; |
|
HB_FALLTHROUGH; |
|
|
|
case HB_UNICODE_COMBINING_CLASS_ATTACHED_BELOW_LEFT: |
|
case HB_UNICODE_COMBINING_CLASS_ATTACHED_BELOW: |
|
pos.y_offset = base_extents.y_bearing + base_extents.height - mark_extents.y_bearing; |
|
/* Never shift up "below" marks. */ |
|
if ((y_gap > 0) == (pos.y_offset > 0)) |
|
{ |
|
base_extents.height -= pos.y_offset; |
|
pos.y_offset = 0; |
|
} |
|
base_extents.height += mark_extents.height; |
|
break; |
|
|
|
case HB_UNICODE_COMBINING_CLASS_DOUBLE_ABOVE: |
|
case HB_UNICODE_COMBINING_CLASS_ABOVE_LEFT: |
|
case HB_UNICODE_COMBINING_CLASS_ABOVE: |
|
case HB_UNICODE_COMBINING_CLASS_ABOVE_RIGHT: |
|
/* Add gap, fall-through. */ |
|
base_extents.y_bearing += y_gap; |
|
base_extents.height -= y_gap; |
|
HB_FALLTHROUGH; |
|
|
|
case HB_UNICODE_COMBINING_CLASS_ATTACHED_ABOVE: |
|
case HB_UNICODE_COMBINING_CLASS_ATTACHED_ABOVE_RIGHT: |
|
pos.y_offset = base_extents.y_bearing - (mark_extents.y_bearing + mark_extents.height); |
|
/* Don't shift down "above" marks too much. */ |
|
if ((y_gap > 0) != (pos.y_offset > 0)) |
|
{ |
|
unsigned int correction = -pos.y_offset / 2; |
|
base_extents.y_bearing += correction; |
|
base_extents.height -= correction; |
|
pos.y_offset += correction; |
|
} |
|
base_extents.y_bearing -= mark_extents.height; |
|
base_extents.height += mark_extents.height; |
|
break; |
|
} |
|
} |
|
|
|
static inline void |
|
position_around_base (const hb_ot_shape_plan_t *plan, |
|
hb_font_t *font, |
|
hb_buffer_t *buffer, |
|
unsigned int base, |
|
unsigned int end) |
|
{ |
|
hb_direction_t horiz_dir = HB_DIRECTION_INVALID; |
|
|
|
buffer->unsafe_to_break (base, end); |
|
|
|
hb_glyph_extents_t base_extents; |
|
if (!font->get_glyph_extents (buffer->info[base].codepoint, |
|
&base_extents)) |
|
{ |
|
/* If extents don't work, zero marks and go home. */ |
|
zero_mark_advances (buffer, base + 1, end); |
|
return; |
|
} |
|
base_extents.x_bearing += buffer->pos[base].x_offset; |
|
base_extents.y_bearing += buffer->pos[base].y_offset; |
|
|
|
unsigned int lig_id = _hb_glyph_info_get_lig_id (&buffer->info[base]); |
|
/* Use integer for num_lig_components such that it doesn't convert to unsigned |
|
* when we divide or multiply by it. */ |
|
int num_lig_components = _hb_glyph_info_get_lig_num_comps (&buffer->info[base]); |
|
|
|
hb_position_t x_offset = 0, y_offset = 0; |
|
if (HB_DIRECTION_IS_FORWARD (buffer->props.direction)) { |
|
x_offset -= buffer->pos[base].x_advance; |
|
y_offset -= buffer->pos[base].y_advance; |
|
} |
|
|
|
hb_glyph_extents_t component_extents = base_extents; |
|
int last_lig_component = -1; |
|
unsigned int last_combining_class = 255; |
|
hb_glyph_extents_t cluster_extents = base_extents; /* Initialization is just to shut gcc up. */ |
|
hb_glyph_info_t *info = buffer->info; |
|
for (unsigned int i = base + 1; i < end; i++) |
|
if (_hb_glyph_info_get_modified_combining_class (&info[i])) |
|
{ |
|
if (num_lig_components > 1) { |
|
unsigned int this_lig_id = _hb_glyph_info_get_lig_id (&info[i]); |
|
int this_lig_component = _hb_glyph_info_get_lig_comp (&info[i]) - 1; |
|
/* Conditions for attaching to the last component. */ |
|
if (!lig_id || lig_id != this_lig_id || this_lig_component >= num_lig_components) |
|
this_lig_component = num_lig_components - 1; |
|
if (last_lig_component != this_lig_component) |
|
{ |
|
last_lig_component = this_lig_component; |
|
last_combining_class = 255; |
|
component_extents = base_extents; |
|
if (unlikely (horiz_dir == HB_DIRECTION_INVALID)) { |
|
if (HB_DIRECTION_IS_HORIZONTAL (plan->props.direction)) |
|
horiz_dir = plan->props.direction; |
|
else |
|
horiz_dir = hb_script_get_horizontal_direction (plan->props.script); |
|
} |
|
if (horiz_dir == HB_DIRECTION_LTR) |
|
component_extents.x_bearing += (this_lig_component * component_extents.width) / num_lig_components; |
|
else |
|
component_extents.x_bearing += ((num_lig_components - 1 - this_lig_component) * component_extents.width) / num_lig_components; |
|
component_extents.width /= num_lig_components; |
|
} |
|
} |
|
|
|
unsigned int this_combining_class = _hb_glyph_info_get_modified_combining_class (&info[i]); |
|
if (last_combining_class != this_combining_class) |
|
{ |
|
last_combining_class = this_combining_class; |
|
cluster_extents = component_extents; |
|
} |
|
|
|
position_mark (plan, font, buffer, cluster_extents, i, this_combining_class); |
|
|
|
buffer->pos[i].x_advance = 0; |
|
buffer->pos[i].y_advance = 0; |
|
buffer->pos[i].x_offset += x_offset; |
|
buffer->pos[i].y_offset += y_offset; |
|
|
|
} else { |
|
if (HB_DIRECTION_IS_FORWARD (buffer->props.direction)) { |
|
x_offset -= buffer->pos[i].x_advance; |
|
y_offset -= buffer->pos[i].y_advance; |
|
} else { |
|
x_offset += buffer->pos[i].x_advance; |
|
y_offset += buffer->pos[i].y_advance; |
|
} |
|
} |
|
} |
|
|
|
static inline void |
|
position_cluster (const hb_ot_shape_plan_t *plan, |
|
hb_font_t *font, |
|
hb_buffer_t *buffer, |
|
unsigned int start, |
|
unsigned int end) |
|
{ |
|
if (end - start < 2) |
|
return; |
|
|
|
/* Find the base glyph */ |
|
hb_glyph_info_t *info = buffer->info; |
|
for (unsigned int i = start; i < end; i++) |
|
if (!HB_UNICODE_GENERAL_CATEGORY_IS_MARK (_hb_glyph_info_get_general_category (&info[i]))) |
|
{ |
|
/* Find mark glyphs */ |
|
unsigned int j; |
|
for (j = i + 1; j < end; j++) |
|
if (!HB_UNICODE_GENERAL_CATEGORY_IS_MARK (_hb_glyph_info_get_general_category (&info[j]))) |
|
break; |
|
|
|
position_around_base (plan, font, buffer, i, j); |
|
|
|
i = j - 1; |
|
} |
|
} |
|
|
|
void |
|
_hb_ot_shape_fallback_position (const hb_ot_shape_plan_t *plan, |
|
hb_font_t *font, |
|
hb_buffer_t *buffer) |
|
{ |
|
_hb_buffer_assert_gsubgpos_vars (buffer); |
|
|
|
unsigned int start = 0; |
|
unsigned int count = buffer->len; |
|
hb_glyph_info_t *info = buffer->info; |
|
for (unsigned int i = 1; i < count; i++) |
|
if (likely (!HB_UNICODE_GENERAL_CATEGORY_IS_MARK (_hb_glyph_info_get_general_category (&info[i])))) { |
|
position_cluster (plan, font, buffer, start, i); |
|
start = i; |
|
} |
|
position_cluster (plan, font, buffer, start, count); |
|
} |
|
|
|
|
|
/* Performs old-style TrueType kerning. */ |
|
void |
|
_hb_ot_shape_fallback_kern (const hb_ot_shape_plan_t *plan, |
|
hb_font_t *font, |
|
hb_buffer_t *buffer) |
|
{ |
|
if (!plan->has_kern) return; |
|
|
|
OT::hb_ot_apply_context_t c (1, font, buffer); |
|
c.set_lookup_mask (plan->kern_mask); |
|
c.set_lookup_props (OT::LookupFlag::IgnoreMarks); |
|
OT::hb_ot_apply_context_t::skipping_iterator_t &skippy_iter = c.iter_input; |
|
skippy_iter.init (&c); |
|
|
|
unsigned int count = buffer->len; |
|
hb_glyph_info_t *info = buffer->info; |
|
hb_glyph_position_t *pos = buffer->pos; |
|
for (unsigned int idx = 0; idx < count;) |
|
{ |
|
skippy_iter.reset (idx, 1); |
|
if (!skippy_iter.next ()) |
|
{ |
|
idx++; |
|
continue; |
|
} |
|
|
|
hb_position_t x_kern, y_kern; |
|
font->get_glyph_kerning_for_direction (info[idx].codepoint, |
|
info[skippy_iter.idx].codepoint, |
|
buffer->props.direction, |
|
&x_kern, &y_kern); |
|
|
|
if (x_kern) |
|
{ |
|
hb_position_t kern1 = x_kern >> 1; |
|
hb_position_t kern2 = x_kern - kern1; |
|
pos[idx].x_advance += kern1; |
|
pos[skippy_iter.idx].x_advance += kern2; |
|
pos[skippy_iter.idx].x_offset += kern2; |
|
buffer->unsafe_to_break (idx, skippy_iter.idx + 1); |
|
} |
|
|
|
if (y_kern) |
|
{ |
|
hb_position_t kern1 = y_kern >> 1; |
|
hb_position_t kern2 = y_kern - kern1; |
|
pos[idx].y_advance += kern1; |
|
pos[skippy_iter.idx].y_advance += kern2; |
|
pos[skippy_iter.idx].y_offset += kern2; |
|
buffer->unsafe_to_break (idx, skippy_iter.idx + 1); |
|
} |
|
|
|
idx = skippy_iter.idx; |
|
} |
|
} |
|
|
|
|
|
/* Adjusts width of various spaces. */ |
|
void |
|
_hb_ot_shape_fallback_spaces (const hb_ot_shape_plan_t *plan, |
|
hb_font_t *font, |
|
hb_buffer_t *buffer) |
|
{ |
|
if (!HB_DIRECTION_IS_HORIZONTAL (buffer->props.direction)) |
|
return; |
|
|
|
hb_glyph_info_t *info = buffer->info; |
|
hb_glyph_position_t *pos = buffer->pos; |
|
unsigned int count = buffer->len; |
|
for (unsigned int i = 0; i < count; i++) |
|
if (_hb_glyph_info_is_unicode_space (&info[i]) && !_hb_glyph_info_ligated (&info[i])) |
|
{ |
|
hb_unicode_funcs_t::space_t space_type = _hb_glyph_info_get_unicode_space_fallback_type (&info[i]); |
|
hb_codepoint_t glyph; |
|
typedef hb_unicode_funcs_t t; |
|
switch (space_type) |
|
{ |
|
case t::NOT_SPACE: /* Shouldn't happen. */ |
|
case t::SPACE: |
|
break; |
|
|
|
case t::SPACE_EM: |
|
case t::SPACE_EM_2: |
|
case t::SPACE_EM_3: |
|
case t::SPACE_EM_4: |
|
case t::SPACE_EM_5: |
|
case t::SPACE_EM_6: |
|
case t::SPACE_EM_16: |
|
pos[i].x_advance = (font->x_scale + ((int) space_type)/2) / (int) space_type; |
|
break; |
|
|
|
case t::SPACE_4_EM_18: |
|
pos[i].x_advance = (int64_t) font->x_scale * 4 / 18; |
|
break; |
|
|
|
case t::SPACE_FIGURE: |
|
for (char u = '0'; u <= '9'; u++) |
|
if (font->get_nominal_glyph (u, &glyph)) |
|
{ |
|
pos[i].x_advance = font->get_glyph_h_advance (glyph); |
|
break; |
|
} |
|
break; |
|
|
|
case t::SPACE_PUNCTUATION: |
|
if (font->get_nominal_glyph ('.', &glyph)) |
|
pos[i].x_advance = font->get_glyph_h_advance (glyph); |
|
else if (font->get_nominal_glyph (',', &glyph)) |
|
pos[i].x_advance = font->get_glyph_h_advance (glyph); |
|
break; |
|
|
|
case t::SPACE_NARROW: |
|
/* Half-space? |
|
* Unicode doc https://unicode.org/charts/PDF/U2000.pdf says ~1/4 or 1/5 of EM. |
|
* However, in my testing, many fonts have their regular space being about that |
|
* size. To me, a percentage of the space width makes more sense. Half is as |
|
* good as any. */ |
|
pos[i].x_advance /= 2; |
|
break; |
|
} |
|
} |
|
}
|
|
|