/*
- * Copyright (C) 2007,2008,2009,2010 Red Hat, Inc.
+ * Copyright © 2007,2008,2009,2010 Red Hat, Inc.
+ * Copyright © 2010 Google, Inc.
*
* This is part of HarfBuzz, a text shaping library.
*
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*
* Red Hat Author(s): Behdad Esfahbod
+ * Google Author(s): Behdad Esfahbod
*/
#ifndef HB_OT_LAYOUT_GPOS_PRIVATE_HH
HB_BEGIN_DECLS
-#define HB_OT_LAYOUT_GPOS_NO_LAST ((unsigned int) -1)
+/* buffer var allocations */
+#define attach_lookback() var.u16[0] /* number of glyphs to go back to attach this glyph to its base */
+#define cursive_chain() var.i16[1] /* character to which this connects, may be positive or negative */
+
/* Shared Tables: ValueRecord, Anchor Table, and MarkArray */
* PosTable (may be NULL) */
#endif
- inline unsigned int get_len () const
+ inline unsigned int get_len (void) const
{ return _hb_popcount32 ((unsigned int) *this); }
- inline unsigned int get_size () const
+ inline unsigned int get_size (void) const
{ return get_len () * Value::static_size; }
- void apply_value (hb_ot_layout_context_t *layout,
- const void *base,
- const Value *values,
- hb_internal_glyph_position_t &glyph_pos) const
+ void apply_value (hb_font_t *font,
+ hb_direction_t direction,
+ const void *base,
+ const Value *values,
+ hb_glyph_position_t &glyph_pos) const
{
unsigned int x_ppem, y_ppem;
unsigned int format = *this;
+ hb_bool_t horizontal = HB_DIRECTION_IS_HORIZONTAL (direction);
if (!format) return;
- /* design units -> fractional pixel */
- if (format & xPlacement) glyph_pos.x_offset += layout->scale_x (get_short (values++));
- if (format & yPlacement) glyph_pos.y_offset += layout->scale_y (get_short (values++));
- if (format & xAdvance) glyph_pos.x_advance += layout->scale_x (get_short (values++));
- if (format & yAdvance) glyph_pos.y_advance += layout->scale_y (get_short (values++));
+ if (format & xPlacement) glyph_pos.x_offset += font->em_scale_x (get_short (values++));
+ if (format & yPlacement) glyph_pos.y_offset += font->em_scale_y (get_short (values++));
+ if (format & xAdvance) {
+ if (likely (horizontal)) glyph_pos.x_advance += font->em_scale_x (get_short (values++)); else values++;
+ }
+ /* y_advance values grow downward but font-space grows upward, hence negation */
+ if (format & yAdvance) {
+ if (unlikely (!horizontal)) glyph_pos.y_advance -= font->em_scale_y (get_short (values++)); else values++;
+ }
if (!has_device ()) return;
- x_ppem = layout->font->x_ppem;
- y_ppem = layout->font->y_ppem;
+ x_ppem = font->x_ppem;
+ y_ppem = font->y_ppem;
if (!x_ppem && !y_ppem) return;
/* pixel -> fractional pixel */
if (format & xPlaDevice) {
- if (x_ppem) glyph_pos.x_offset += (base + get_device (values++)).get_x_delta (layout); else values++;
+ if (x_ppem) glyph_pos.x_offset += (base + get_device (values++)).get_x_delta (font); else values++;
}
if (format & yPlaDevice) {
- if (y_ppem) glyph_pos.y_offset += (base + get_device (values++)).get_y_delta (layout); else values++;
+ if (y_ppem) glyph_pos.y_offset += (base + get_device (values++)).get_y_delta (font); else values++;
}
if (format & xAdvDevice) {
- if (x_ppem) glyph_pos.x_advance += (base + get_device (values++)).get_x_delta (layout); else values++;
+ if (horizontal && x_ppem) glyph_pos.x_advance += (base + get_device (values++)).get_x_delta (font); else values++;
}
if (format & yAdvDevice) {
- if (y_ppem) glyph_pos.y_advance += (base + get_device (values++)).get_y_delta (layout); else values++;
+ /* y_advance values grow downward but font-space grows upward, hence negation */
+ if (!horizontal && y_ppem) glyph_pos.y_advance -= (base + get_device (values++)).get_y_delta (font); else values++;
}
}
public:
- inline bool has_device () const {
+ inline bool has_device (void) const {
unsigned int format = *this;
return (format & devices) != 0;
}
friend struct Anchor;
private:
- inline void get_anchor (hb_ot_layout_context_t *layout, hb_codepoint_t glyph_id HB_UNUSED,
+ inline void get_anchor (hb_font_t *font, hb_codepoint_t glyph_id HB_UNUSED,
hb_position_t *x, hb_position_t *y) const
{
- *x = layout->scale_x (xCoordinate);
- *y = layout->scale_y (yCoordinate);
+ *x = font->em_scale_x (xCoordinate);
+ *y = font->em_scale_y (yCoordinate);
}
inline bool sanitize (hb_sanitize_context_t *c) {
friend struct Anchor;
private:
- inline void get_anchor (hb_ot_layout_context_t *layout, hb_codepoint_t glyph_id,
+ inline void get_anchor (hb_font_t *font, hb_codepoint_t glyph_id,
hb_position_t *x, hb_position_t *y) const
{
- unsigned int x_ppem = layout->font->x_ppem;
- unsigned int y_ppem = layout->font->y_ppem;
+ unsigned int x_ppem = font->x_ppem;
+ unsigned int y_ppem = font->y_ppem;
hb_position_t cx, cy;
- hb_bool_t ret;
+ hb_bool_t ret = false;
if (x_ppem || y_ppem)
- ret = hb_font_get_contour_point (layout->font, layout->face, anchorPoint, glyph_id, &cx, &cy);
- *x = x_ppem && ret ? cx : layout->scale_x (xCoordinate);
- *y = y_ppem && ret ? cy : layout->scale_y (yCoordinate);
+ ret = hb_font_get_glyph_contour_point_for_origin (font, glyph_id, anchorPoint, HB_DIRECTION_LTR, &cx, &cy);
+ *x = x_ppem && ret ? cx : font->em_scale_x (xCoordinate);
+ *y = y_ppem && ret ? cy : font->em_scale_y (yCoordinate);
}
inline bool sanitize (hb_sanitize_context_t *c) {
friend struct Anchor;
private:
- inline void get_anchor (hb_ot_layout_context_t *layout, hb_codepoint_t glyph_id HB_UNUSED,
+ inline void get_anchor (hb_font_t *font, hb_codepoint_t glyph_id HB_UNUSED,
hb_position_t *x, hb_position_t *y) const
{
- *x = layout->scale_x (xCoordinate);
- *y = layout->scale_y (yCoordinate);
-
- /* pixel -> fractional pixel */
- if (layout->font->x_ppem)
- *x += (this+xDeviceTable).get_x_delta (layout);
- if (layout->font->y_ppem)
- *y += (this+yDeviceTable).get_x_delta (layout);
+ *x = font->em_scale_x (xCoordinate);
+ *y = font->em_scale_y (yCoordinate);
+
+ if (font->x_ppem)
+ *x += (this+xDeviceTable).get_x_delta (font);
+ if (font->y_ppem)
+ *y += (this+yDeviceTable).get_x_delta (font);
}
inline bool sanitize (hb_sanitize_context_t *c) {
struct Anchor
{
- inline void get_anchor (hb_ot_layout_context_t *layout, hb_codepoint_t glyph_id,
+ inline void get_anchor (hb_font_t *font, hb_codepoint_t glyph_id,
hb_position_t *x, hb_position_t *y) const
{
*x = *y = 0;
switch (u.format) {
- case 1: u.format1.get_anchor (layout, glyph_id, x, y); return;
- case 2: u.format2.get_anchor (layout, glyph_id, x, y); return;
- case 3: u.format3.get_anchor (layout, glyph_id, x, y); return;
- default: return;
+ case 1: u.format1.get_anchor (font, glyph_id, x, y); return;
+ case 2: u.format2.get_anchor (font, glyph_id, x, y); return;
+ case 3: u.format3.get_anchor (font, glyph_id, x, y); return;
+ default: return;
}
}
hb_position_t mark_x, mark_y, base_x, base_y;
- mark_anchor.get_anchor (c->layout, c->buffer->info[c->buffer->i].codepoint, &mark_x, &mark_y);
- glyph_anchor.get_anchor (c->layout, c->buffer->info[glyph_pos].codepoint, &base_x, &base_y);
+ mark_anchor.get_anchor (c->font, c->buffer->info[c->buffer->i].codepoint, &mark_x, &mark_y);
+ glyph_anchor.get_anchor (c->font, c->buffer->info[glyph_pos].codepoint, &base_x, &base_y);
- hb_internal_glyph_position_t &o = c->buffer->pos[c->buffer->i];
- o.x_offset = base_x - mark_x;
- o.y_offset = base_y - mark_y;
- o.back = c->buffer->i - glyph_pos;
+ hb_glyph_position_t &o = c->buffer->pos[c->buffer->i];
+ o.x_offset = base_x - mark_x;
+ o.y_offset = base_y - mark_y;
+ o.attach_lookback() = c->buffer->i - glyph_pos;
c->buffer->i++;
return true;
if (likely (index == NOT_COVERED))
return false;
- valueFormat.apply_value (c->layout, this, values, c->buffer->pos[c->buffer->i]);
+ valueFormat.apply_value (c->font, c->direction, this,
+ values, c->buffer->pos[c->buffer->i]);
c->buffer->i++;
return true;
if (likely (index >= valueCount))
return false;
- valueFormat.apply_value (c->layout, this,
+ valueFormat.apply_value (c->font, c->direction, this,
&values[index * valueFormat.get_len ()],
c->buffer->pos[c->buffer->i]);
{
if (c->buffer->info[pos].codepoint == record->secondGlyph)
{
- valueFormats[0].apply_value (c->layout, this, &record->values[0], c->buffer->pos[c->buffer->i]);
- valueFormats[1].apply_value (c->layout, this, &record->values[len1], c->buffer->pos[pos]);
+ valueFormats[0].apply_value (c->font, c->direction, this,
+ &record->values[0], c->buffer->pos[c->buffer->i]);
+ valueFormats[1].apply_value (c->font, c->direction, this,
+ &record->values[len1], c->buffer->pos[pos]);
if (len2)
pos++;
c->buffer->i = pos;
return false;
unsigned int j = c->buffer->i + 1;
- while (_hb_ot_layout_skip_mark (c->layout->face, &c->buffer->info[j], c->lookup_flag, NULL))
+ while (_hb_ot_layout_skip_mark (c->face, &c->buffer->info[j], c->lookup_props, NULL))
{
if (unlikely (j == end))
return false;
return false;
unsigned int j = c->buffer->i + 1;
- while (_hb_ot_layout_skip_mark (c->layout->face, &c->buffer->info[j], c->lookup_flag, NULL))
+ while (_hb_ot_layout_skip_mark (c->face, &c->buffer->info[j], c->lookup_props, NULL))
{
if (unlikely (j == end))
return false;
return false;
const Value *v = &values[record_len * (klass1 * class2Count + klass2)];
- valueFormat1.apply_value (c->layout, this, v, c->buffer->pos[c->buffer->i]);
- valueFormat2.apply_value (c->layout, this, v + len1, c->buffer->pos[j]);
+ valueFormat1.apply_value (c->font, c->direction, this,
+ v, c->buffer->pos[c->buffer->i]);
+ valueFormat2.apply_value (c->font, c->direction, this,
+ v + len1, c->buffer->pos[j]);
if (len2)
j++;
inline bool apply (hb_apply_context_t *c) const
{
TRACE_APPLY ();
- /* Now comes the messiest part of the whole OpenType
- specification. At first glance, cursive connections seem easy
- to understand, but there are pitfalls! The reason is that
- the specs don't mention how to compute the advance values
- resp. glyph offsets. I was told it would be an omission, to
- be fixed in the next OpenType version... Again many thanks to
- Andrei Burago <andreib@microsoft.com> for clarifications.
-
- Consider the following example:
-
- | xadv1 |
- +---------+
- | |
- +-----+--+ 1 |
- | | .| |
- | 0+--+------+
- | 2 |
- | |
- 0+--------+
- | xadv2 |
-
- glyph1: advance width = 12
- anchor point = (3,1)
-
- glyph2: advance width = 11
- anchor point = (9,4)
-
- LSB is 1 for both glyphs (so the boxes drawn above are glyph
- bboxes). Writing direction is R2L; `0' denotes the glyph's
- coordinate origin.
-
- Now the surprising part: The advance width of the *left* glyph
- (resp. of the *bottom* glyph) will be modified, no matter
- whether the writing direction is L2R or R2L (resp. T2B or
- B2T)! This assymetry is caused by the fact that the glyph's
- coordinate origin is always the lower left corner for all
- writing directions.
-
- Continuing the above example, we can compute the new
- (horizontal) advance width of glyph2 as
-
- 9 - 3 = 6 ,
-
- and the new vertical offset of glyph2 as
-
- 1 - 4 = -3 .
-
-
- Vertical writing direction is far more complicated:
-
- a) Assuming that we recompute the advance height of the lower glyph:
-
- --
- +---------+
- -- | |
- +-----+--+ 1 | yadv1
- | | .| |
- yadv2 | 0+--+------+ -- BSB1 --
- | 2 | -- -- y_offset
- | |
- BSB2 -- 0+--------+ --
- -- --
-
- glyph1: advance height = 6
- anchor point = (3,1)
-
- glyph2: advance height = 7
- anchor point = (9,4)
-
- TSB is 1 for both glyphs; writing direction is T2B.
-
-
- BSB1 = yadv1 - (TSB1 + ymax1)
- BSB2 = yadv2 - (TSB2 + ymax2)
- y_offset = y2 - y1
-
- vertical advance width of glyph2
- = y_offset + BSB2 - BSB1
- = (y2 - y1) + (yadv2 - (TSB2 + ymax2)) - (yadv1 - (TSB1 + ymax1))
- = y2 - y1 + yadv2 - TSB2 - ymax2 - (yadv1 - TSB1 - ymax1)
- = y2 - y1 + yadv2 - TSB2 - ymax2 - yadv1 + TSB1 + ymax1
-
-
- b) Assuming that we recompute the advance height of the upper glyph:
-
- -- --
- +---------+ -- TSB1
- -- -- | |
- TSB2 -- +-----+--+ 1 | yadv1 ymax1
- | | .| |
- yadv2 | 0+--+------+ -- --
- ymax2 | 2 | -- y_offset
- | |
- -- 0+--------+ --
- --
-
- glyph1: advance height = 6
- anchor point = (3,1)
-
- glyph2: advance height = 7
- anchor point = (9,4)
-
- TSB is 1 for both glyphs; writing direction is T2B.
-
- y_offset = y2 - y1
-
- vertical advance width of glyph2
- = TSB1 + ymax1 + y_offset - (TSB2 + ymax2)
- = TSB1 + ymax1 + y2 - y1 - TSB2 - ymax2
-
-
- Comparing a) with b) shows that b) is easier to compute. I'll wait
- for a reply from Andrei to see what should really be implemented...
-
- Since horizontal advance widths or vertical advance heights
- can be used alone but not together, no ambiguity occurs. */
-
- struct hb_ot_layout_context_t::info_t::gpos_t *gpi = &c->layout->info.gpos;
- hb_codepoint_t last_pos = gpi->last;
- gpi->last = HB_OT_LAYOUT_GPOS_NO_LAST;
/* We don't handle mark glyphs here. */
- if (c->property == HB_OT_LAYOUT_GLYPH_CLASS_MARK)
+ if (c->property & HB_OT_LAYOUT_GLYPH_CLASS_MARK)
return false;
- unsigned int index = (this+coverage) (c->buffer->info[c->buffer->i].codepoint);
- if (likely (index == NOT_COVERED))
+ unsigned int end = MIN (c->buffer->len, c->buffer->i + c->context_length);
+ if (unlikely (c->buffer->i + 2 > end))
return false;
- const EntryExitRecord &record = entryExitRecord[index];
-
- if (last_pos == HB_OT_LAYOUT_GPOS_NO_LAST || !record.entryAnchor)
- goto end;
-
- hb_position_t entry_x, entry_y;
- (this+record.entryAnchor).get_anchor (c->layout, c->buffer->info[c->buffer->i].codepoint, &entry_x, &entry_y);
-
- /* TODO vertical */
+ const EntryExitRecord &this_record = entryExitRecord[(this+coverage) (c->buffer->info[c->buffer->i].codepoint)];
+ if (!this_record.exitAnchor)
+ return false;
- if (c->buffer->props.direction == HB_DIRECTION_RTL)
- {
- /* advance is absolute, not relative */
- c->buffer->pos[c->buffer->i].x_advance = entry_x - gpi->anchor_x;
- }
- else
+ unsigned int j = c->buffer->i + 1;
+ while (_hb_ot_layout_skip_mark (c->face, &c->buffer->info[j], c->lookup_props, NULL))
{
- /* advance is absolute, not relative */
- c->buffer->pos[last_pos].x_advance = gpi->anchor_x - entry_x;
+ if (unlikely (j == end))
+ return false;
+ j++;
}
- if (c->lookup_flag & LookupFlag::RightToLeft)
- {
- c->buffer->pos[last_pos].cursive_chain = last_pos - c->buffer->i;
- c->buffer->pos[last_pos].y_offset = entry_y - gpi->anchor_y;
- }
- else
- {
- c->buffer->pos[c->buffer->i].cursive_chain = c->buffer->i - last_pos;
- c->buffer->pos[c->buffer->i].y_offset = gpi->anchor_y - entry_y;
+ const EntryExitRecord &next_record = entryExitRecord[(this+coverage) (c->buffer->info[j].codepoint)];
+ if (!next_record.entryAnchor)
+ return false;
+
+ unsigned int i = c->buffer->i;
+
+ hb_position_t entry_x, entry_y, exit_x, exit_y;
+ (this+this_record.exitAnchor).get_anchor (c->font, c->buffer->info[i].codepoint, &exit_x, &exit_y);
+ (this+next_record.entryAnchor).get_anchor (c->font, c->buffer->info[j].codepoint, &entry_x, &entry_y);
+
+ hb_glyph_position_t *pos = c->buffer->pos;
+
+ hb_position_t d;
+ /* Main-direction adjustment */
+ switch (c->direction) {
+ case HB_DIRECTION_LTR:
+ pos[i].x_advance = exit_x + pos[i].x_offset;
+
+ d = entry_x + pos[j].x_offset;
+ pos[j].x_advance -= d;
+ pos[j].x_offset -= d;
+ break;
+ case HB_DIRECTION_RTL:
+ d = exit_x + pos[i].x_offset;
+ pos[i].x_advance -= d;
+ pos[i].x_offset -= d;
+
+ pos[j].x_advance = entry_x + pos[j].x_offset;
+ break;
+ case HB_DIRECTION_TTB:
+ pos[i].y_advance = exit_y + pos[i].y_offset;
+
+ d = entry_y + pos[j].y_offset;
+ pos[j].y_advance -= d;
+ pos[j].y_offset -= d;
+ break;
+ case HB_DIRECTION_BTT:
+ d = exit_y + pos[i].y_offset;
+ pos[i].y_advance -= d;
+ pos[i].y_offset -= d;
+
+ pos[j].y_advance = entry_y;
+ break;
+ case HB_DIRECTION_INVALID:
+ default:
+ break;
}
- end:
- if (record.exitAnchor)
- {
- gpi->last = c->buffer->i;
- (this+record.exitAnchor).get_anchor (c->layout, c->buffer->info[c->buffer->i].codepoint, &gpi->anchor_x, &gpi->anchor_y);
+ /* Cross-direction adjustment */
+ if (c->lookup_props & LookupFlag::RightToLeft) {
+ pos[i].cursive_chain() = j - i;
+ if (likely (HB_DIRECTION_IS_HORIZONTAL (c->direction)))
+ pos[i].y_offset = entry_y - exit_y;
+ else
+ pos[i].x_offset = entry_x - exit_x;
+ } else {
+ pos[j].cursive_chain() = i - j;
+ if (likely (HB_DIRECTION_IS_HORIZONTAL (c->direction)))
+ pos[j].y_offset = exit_y - entry_y;
+ else
+ pos[j].x_offset = exit_x - entry_x;
}
- c->buffer->i++;
+ c->buffer->i = j;
return true;
}
if (unlikely (!j))
return false;
j--;
- } while (_hb_ot_layout_skip_mark (c->layout->face, &c->buffer->info[j], LookupFlag::IgnoreMarks, &property));
+ } while (_hb_ot_layout_skip_mark (c->face, &c->buffer->info[j], LookupFlag::IgnoreMarks, &property));
/* The following assertion is too strong, so we've disabled it. */
- if (false && !(property & HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH))
- return false;
+ if (!(property & HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH))
+ {/*return false;*/}
unsigned int base_index = (this+baseCoverage) (c->buffer->info[j].codepoint);
if (base_index == NOT_COVERED)
if (unlikely (!j))
return false;
j--;
- } while (_hb_ot_layout_skip_mark (c->layout->face, &c->buffer->info[j], LookupFlag::IgnoreMarks, &property));
+ } while (_hb_ot_layout_skip_mark (c->face, &c->buffer->info[j], LookupFlag::IgnoreMarks, &property));
/* The following assertion is too strong, so we've disabled it. */
- if (false && !(property & HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE))
- return false;
+ if (!(property & HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE))
+ {/*return false;*/}
unsigned int lig_index = (this+ligatureCoverage) (c->buffer->info[j].codepoint);
if (lig_index == NOT_COVERED)
* is identical to the ligature ID of the found ligature. If yes, we
* can directly use the component index. If not, we attach the mark
* glyph to the last component of the ligature. */
- if (c->buffer->info[j].lig_id && c->buffer->info[j].lig_id == c->buffer->info[c->buffer->i].lig_id && c->buffer->info[c->buffer->i].component)
+ if (c->buffer->info[j].lig_id() && c->buffer->info[j].lig_id() == c->buffer->info[c->buffer->i].lig_id() && c->buffer->info[c->buffer->i].lig_comp())
{
- comp_index = c->buffer->info[c->buffer->i].component - 1;
+ comp_index = c->buffer->info[c->buffer->i].lig_comp() - 1;
if (comp_index >= comp_count)
comp_index = comp_count - 1;
}
if (unlikely (!j))
return false;
j--;
- } while (_hb_ot_layout_skip_mark (c->layout->face, &c->buffer->info[j], c->lookup_flag, &property));
+ } while (_hb_ot_layout_skip_mark (c->face, &c->buffer->info[j], c->lookup_props, &property));
if (!(property & HB_OT_LAYOUT_GLYPH_CLASS_MARK))
return false;
/* Two marks match only if they belong to the same base, or same component
* of the same ligature. That is, the component numbers must match, and
* if those are non-zero, the ligid number should also match. */
- if ((c->buffer->info[j].component != c->buffer->info[c->buffer->i].component) ||
- (c->buffer->info[j].component && c->buffer->info[j].lig_id != c->buffer->info[c->buffer->i].lig_id))
+ if ((c->buffer->info[j].lig_comp() != c->buffer->info[c->buffer->i].lig_comp()) ||
+ (c->buffer->info[j].lig_comp() && c->buffer->info[j].lig_id() != c->buffer->info[c->buffer->i].lig_id()))
return false;
unsigned int mark2_index = (this+mark2Coverage) (c->buffer->info[j].codepoint);
inline const PosLookupSubTable& get_subtable (unsigned int i) const
{ return this+CastR<OffsetArrayOf<PosLookupSubTable> > (subTable)[i]; }
- inline bool apply_once (hb_ot_layout_context_t *layout,
+ inline bool apply_once (hb_font_t *font,
hb_buffer_t *buffer,
hb_mask_t lookup_mask,
unsigned int context_length,
unsigned int lookup_type = get_type ();
hb_apply_context_t c[1] = {{0}};
- c->layout = layout;
+ c->font = font;
+ c->face = font->face;
c->buffer = buffer;
+ c->direction = buffer->props.direction;
c->lookup_mask = lookup_mask;
c->context_length = context_length;
c->nesting_level_left = nesting_level_left;
- c->lookup_flag = get_flag ();
+ c->lookup_props = get_props ();
- if (!_hb_ot_layout_check_glyph_property (c->layout->face, &c->buffer->info[c->buffer->i], c->lookup_flag, &c->property))
+ if (!_hb_ot_layout_check_glyph_property (c->face, &c->buffer->info[c->buffer->i], c->lookup_props, &c->property))
return false;
for (unsigned int i = 0; i < get_subtable_count (); i++)
return false;
}
- inline bool apply_string (hb_ot_layout_context_t *layout,
+ inline bool apply_string (hb_font_t *font,
hb_buffer_t *buffer,
hb_mask_t mask) const
{
if (unlikely (!buffer->len))
return false;
- layout->info.gpos.last = HB_OT_LAYOUT_GPOS_NO_LAST; /* no last valid glyph for cursive pos. */
-
buffer->i = 0;
while (buffer->i < buffer->len)
{
- bool done;
- if (buffer->info[buffer->i].mask & mask)
- {
- done = apply_once (layout, buffer, mask, NO_CONTEXT, MAX_NESTING_LEVEL);
- ret |= done;
- }
+ if ((buffer->info[buffer->i].mask & mask) &&
+ apply_once (font, buffer, mask, NO_CONTEXT, MAX_NESTING_LEVEL))
+ ret = true;
else
- {
- done = false;
- /* Contrary to properties defined in GDEF, user-defined properties
- will always stop a possible cursive positioning. */
- layout->info.gpos.last = HB_OT_LAYOUT_GPOS_NO_LAST;
- }
-
- if (!done)
buffer->i++;
}
inline const PosLookup& get_lookup (unsigned int i) const
{ return CastR<PosLookup> (GSUBGPOS::get_lookup (i)); }
- inline bool position_lookup (hb_ot_layout_context_t *layout,
+ inline bool position_lookup (hb_font_t *font,
hb_buffer_t *buffer,
unsigned int lookup_index,
hb_mask_t mask) const
- { return get_lookup (lookup_index).apply_string (layout, buffer, mask); }
+ { return get_lookup (lookup_index).apply_string (font, buffer, mask); }
+
+ static inline void position_finish (hb_buffer_t *buffer);
inline bool sanitize (hb_sanitize_context_t *c) {
TRACE_SANITIZE ();
};
+static void
+fix_cursive_minor_offset (hb_glyph_position_t *pos, unsigned int i, hb_direction_t direction)
+{
+ unsigned int j = pos[i].cursive_chain();
+ if (likely (!j))
+ return;
+
+ j += i;
+
+ pos[i].cursive_chain() = 0;
+
+ fix_cursive_minor_offset (pos, j, direction);
+
+ if (HB_DIRECTION_IS_HORIZONTAL (direction))
+ pos[i].y_offset += pos[j].y_offset;
+ else
+ pos[i].x_offset += pos[j].x_offset;
+}
+
+static void
+fix_mark_attachment (hb_glyph_position_t *pos, unsigned int i, hb_direction_t direction)
+{
+ if (likely (!(pos[i].attach_lookback())))
+ return;
+
+ unsigned int j = i - pos[i].attach_lookback();
+
+ pos[i].x_advance = 0;
+ pos[i].y_advance = 0;
+ pos[i].x_offset += pos[j].x_offset;
+ pos[i].y_offset += pos[j].y_offset;
+
+ if (HB_DIRECTION_IS_FORWARD (direction))
+ for (unsigned int k = j; k < i; k++) {
+ pos[i].x_offset -= pos[k].x_advance;
+ pos[i].y_offset -= pos[k].y_advance;
+ }
+ else
+ for (unsigned int k = j + 1; k < i + 1; k++) {
+ pos[i].x_offset += pos[k].x_advance;
+ pos[i].y_offset += pos[k].y_advance;
+ }
+}
+
+void
+GPOS::position_finish (hb_buffer_t *buffer)
+{
+ unsigned int len;
+ hb_glyph_position_t *pos = hb_buffer_get_glyph_positions (buffer, &len);
+ hb_direction_t direction = buffer->props.direction;
+
+ /* Handle cursive connections */
+ for (unsigned int i = 0; i < len; i++)
+ {
+ fix_cursive_minor_offset (pos, i, direction);
+ }
+
+ /* Handle attachments */
+ for (unsigned int i = 0; i < len; i++)
+ {
+ fix_mark_attachment (pos, i, direction);
+ }
+}
+
+
/* Out-of-class implementation for methods recursing */
inline bool ExtensionPos::apply (hb_apply_context_t *c) const
static inline bool position_lookup (hb_apply_context_t *c, unsigned int lookup_index)
{
- const GPOS &gpos = *(c->layout->face->ot_layout->gpos);
+ const GPOS &gpos = *(c->face->ot_layout->gpos);
const PosLookup &l = gpos.get_lookup (lookup_index);
if (unlikely (c->nesting_level_left == 0))
if (unlikely (c->context_length < 1))
return false;
- return l.apply_once (c->layout, c->buffer, c->lookup_mask, c->context_length, c->nesting_level_left - 1);
+ return l.apply_once (c->font, c->buffer, c->lookup_mask, c->context_length, c->nesting_level_left - 1);
}
+#undef attach_lookback
+#undef cursive_chain
+
+
HB_END_DECLS
#endif /* HB_OT_LAYOUT_GPOS_PRIVATE_HH */