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diff --git a/gfx/harfbuzz/src/hb-ot-shape-fallback.cc b/gfx/harfbuzz/src/hb-ot-shape-fallback.cc
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+/*
+ * 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 dont 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 - mark_extents.width / 2 - mark_extents.x_bearing;
+ break;
+ } else if (buffer->props.direction == HB_DIRECTION_RTL) {
+ pos.x_offset += base_extents.x_bearing + base_extents.width - 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;
+ 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]);
+ unsigned 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;
+ unsigned int last_lig_component = (unsigned int) -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]);
+ unsigned 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_apply_context_t c (1, font, buffer);
+ c.set_lookup_mask (plan->kern_mask);
+ c.set_lookup_props (OT::LookupFlag::IgnoreMarks);
+ OT::hb_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;
+ }
+
+ 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;
+ }
+
+ 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 = 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 http://www.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;
+ }
+ }
+}