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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 00:47:55 +0000
commit26a029d407be480d791972afb5975cf62c9360a6 (patch)
treef435a8308119effd964b339f76abb83a57c29483 /gfx/harfbuzz/src/hb-ot-shape-fallback.cc
parentInitial commit. (diff)
downloadfirefox-26a029d407be480d791972afb5975cf62c9360a6.tar.xz
firefox-26a029d407be480d791972afb5975cf62c9360a6.zip
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'gfx/harfbuzz/src/hb-ot-shape-fallback.cc')
-rw-r--r--gfx/harfbuzz/src/hb-ot-shape-fallback.cc615
1 files changed, 615 insertions, 0 deletions
diff --git a/gfx/harfbuzz/src/hb-ot-shape-fallback.cc b/gfx/harfbuzz/src/hb-ot-shape-fallback.cc
new file mode 100644
index 0000000000..b2eedb027b
--- /dev/null
+++ b/gfx/harfbuzz/src/hb-ot-shape-fallback.cc
@@ -0,0 +1,615 @@
+/*
+ * 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.hh"
+
+#ifndef HB_NO_OT_SHAPE
+
+#include "hb-ot-shape-fallback.hh"
+#include "hb-kern.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 & qamats qatan */
+ 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 & holam haser for vav */
+ 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_mark_position_recategorize_marks (const hb_ot_shape_plan_t *plan HB_UNUSED,
+ hb_font_t *font HB_UNUSED,
+ hb_buffer_t *buffer)
+{
+#ifdef HB_NO_OT_SHAPE_FALLBACK
+ return;
+#endif
+
+ 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,
+ bool adjust_offsets_when_zeroing)
+{
+ 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)
+ {
+ if (adjust_offsets_when_zeroing)
+ {
+ buffer->pos[i].x_offset -= buffer->pos[i].x_advance;
+ buffer->pos[i].y_offset -= buffer->pos[i].y_advance;
+ }
+ 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_UNUSED,
+ 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))
+ {
+ 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,
+ bool adjust_offsets_when_zeroing)
+{
+ 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, adjust_offsets_when_zeroing);
+ return;
+ }
+ base_extents.y_bearing += buffer->pos[base].y_offset;
+ /* Use horizontal advance for horizontal positioning.
+ * Generally a better idea. Also works for zero-ink glyphs. See:
+ * https://github.com/harfbuzz/harfbuzz/issues/1532 */
+ base_extents.x_bearing = 0;
+ base_extents.width = font->get_glyph_h_advance (buffer->info[base].codepoint);
+
+ 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,
+ bool adjust_offsets_when_zeroing)
+{
+ 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_glyph_info_is_unicode_mark (&info[i]))
+ {
+ /* Find mark glyphs */
+ unsigned int j;
+ for (j = i + 1; j < end; j++)
+ if (!_hb_glyph_info_is_unicode_mark (&info[j]))
+ break;
+
+ position_around_base (plan, font, buffer, i, j, adjust_offsets_when_zeroing);
+
+ i = j - 1;
+ }
+}
+
+void
+_hb_ot_shape_fallback_mark_position (const hb_ot_shape_plan_t *plan,
+ hb_font_t *font,
+ hb_buffer_t *buffer,
+ bool adjust_offsets_when_zeroing)
+{
+#ifdef HB_NO_OT_SHAPE_FALLBACK
+ return;
+#endif
+
+ if (!buffer->message (font, "start fallback mark"))
+ return;
+
+ _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_glyph_info_is_unicode_mark (&info[i]))) {
+ position_cluster (plan, font, buffer, start, i, adjust_offsets_when_zeroing);
+ start = i;
+ }
+ position_cluster (plan, font, buffer, start, count, adjust_offsets_when_zeroing);
+
+ (void) buffer->message (font, "end fallback mark");
+}
+
+
+#ifndef HB_DISABLE_DEPRECATED
+struct hb_ot_shape_fallback_kern_driver_t
+{
+ hb_ot_shape_fallback_kern_driver_t (hb_font_t *font_,
+ hb_buffer_t *buffer) :
+ font (font_), direction (buffer->props.direction) {}
+
+ hb_position_t get_kerning (hb_codepoint_t first, hb_codepoint_t second) const
+ {
+ hb_position_t kern = 0;
+ font->get_glyph_kerning_for_direction (first, second,
+ direction,
+ &kern, &kern);
+ return kern;
+ }
+
+ hb_font_t *font;
+ hb_direction_t direction;
+};
+#endif
+
+/* Performs font-assisted kerning. */
+void
+_hb_ot_shape_fallback_kern (const hb_ot_shape_plan_t *plan,
+ hb_font_t *font,
+ hb_buffer_t *buffer)
+{
+#ifdef HB_NO_OT_SHAPE_FALLBACK
+ return;
+#endif
+
+#ifndef HB_DISABLE_DEPRECATED
+ if (HB_DIRECTION_IS_HORIZONTAL (buffer->props.direction) ?
+ !font->has_glyph_h_kerning_func () :
+ !font->has_glyph_v_kerning_func ())
+ return;
+
+ if (!buffer->message (font, "start fallback kern"))
+ return;
+
+ bool reverse = HB_DIRECTION_IS_BACKWARD (buffer->props.direction);
+
+ if (reverse)
+ buffer->reverse ();
+
+ hb_ot_shape_fallback_kern_driver_t driver (font, buffer);
+ OT::hb_kern_machine_t<hb_ot_shape_fallback_kern_driver_t> machine (driver);
+ machine.kern (font, buffer, plan->kern_mask, false);
+
+ if (reverse)
+ buffer->reverse ();
+
+ (void) buffer->message (font, "end fallback kern");
+#endif
+}
+
+
+/* Adjusts width of various spaces. */
+void
+_hb_ot_shape_fallback_spaces (const hb_ot_shape_plan_t *plan HB_UNUSED,
+ hb_font_t *font,
+ hb_buffer_t *buffer)
+{
+ hb_glyph_info_t *info = buffer->info;
+ hb_glyph_position_t *pos = buffer->pos;
+ bool horizontal = HB_DIRECTION_IS_HORIZONTAL (buffer->props.direction);
+ 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]))
+ {
+ /* If font had no ASCII space and we used the invisible glyph, give it a 1/4 EM default advance. */
+ if (buffer->invisible && info[i].codepoint == buffer->invisible)
+ {
+ if (horizontal)
+ pos[i].x_advance = +font->x_scale / 4;
+ else
+ pos[i].y_advance = -font->y_scale / 4;
+ }
+
+ 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:
+ if (horizontal)
+ pos[i].x_advance = +(font->x_scale + ((int) space_type)/2) / (int) space_type;
+ else
+ pos[i].y_advance = -(font->y_scale + ((int) space_type)/2) / (int) space_type;
+ break;
+
+ case t::SPACE_4_EM_18:
+ if (horizontal)
+ pos[i].x_advance = (int64_t) +font->x_scale * 4 / 18;
+ else
+ pos[i].y_advance = (int64_t) -font->y_scale * 4 / 18;
+ break;
+
+ case t::SPACE_FIGURE:
+ for (char u = '0'; u <= '9'; u++)
+ if (font->get_nominal_glyph (u, &glyph))
+ {
+ if (horizontal)
+ pos[i].x_advance = font->get_glyph_h_advance (glyph);
+ else
+ pos[i].y_advance = font->get_glyph_v_advance (glyph);
+ break;
+ }
+ break;
+
+ case t::SPACE_PUNCTUATION:
+ if (font->get_nominal_glyph ('.', &glyph) ||
+ font->get_nominal_glyph (',', &glyph))
+ {
+ if (horizontal)
+ pos[i].x_advance = font->get_glyph_h_advance (glyph);
+ else
+ pos[i].y_advance = font->get_glyph_v_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. */
+ if (horizontal)
+ pos[i].x_advance /= 2;
+ else
+ pos[i].y_advance /= 2;
+ break;
+ }
+ }
+}
+
+
+#endif