[GPOS] Merge attach_chain() and cursive_chain()
Differentiate, using new attach_type().
diff --git a/src/hb-ot-layout-gpos-table.hh b/src/hb-ot-layout-gpos-table.hh
index 8c83cf2..b349524 100644
--- a/src/hb-ot-layout-gpos-table.hh
+++ b/src/hb-ot-layout-gpos-table.hh
@@ -36,8 +36,17 @@
/* buffer **position** var allocations */
-#define attach_chain() var.i16[0] /* glyph to which this attaches to, relative to current glyphs; negative for going back. */
-#define cursive_chain() var.i16[1] /* glyph to which this connects, may be positive or negative */
+#define attach_chain() var.i16[0] /* glyph to which this attaches to, relative to current glyphs; negative for going back, positive for forward. */
+#define attach_type() var.u8[2] /* attachment type */
+/* Note! if attach_chain() is zero, the value of attach_type() is irrelevant. */
+
+enum attach_type_t {
+ ATTACH_TYPE_NONE = 0X00,
+
+ /* Each attachment should be either a mark or a cursive; can't be both. */
+ ATTACH_TYPE_MARK = 0X01,
+ ATTACH_TYPE_CURSIVE = 0X02,
+};
/* Shared Tables: ValueRecord, Anchor Table, and MarkArray */
@@ -425,6 +434,7 @@
hb_glyph_position_t &o = buffer->cur_pos();
o.x_offset = base_x - mark_x;
o.y_offset = base_y - mark_y;
+ o.attach_type() = ATTACH_TYPE_MARK;
o.attach_chain() = (int) glyph_pos - (int) buffer->idx;
buffer->scratch_flags |= HB_BUFFER_SCRATCH_FLAG_HAS_GPOS_ATTACHMENT;
@@ -993,7 +1003,8 @@
*/
reverse_cursive_minor_offset (pos, child, c->direction, parent);
- pos[child].cursive_chain() = (int) parent - (int) child;
+ pos[child].attach_type() = ATTACH_TYPE_CURSIVE;
+ pos[child].attach_chain() = (int) parent - (int) child;
buffer->scratch_flags |= HB_BUFFER_SCRATCH_FLAG_HAS_GPOS_CURSIVE;
if (likely (HB_DIRECTION_IS_HORIZONTAL (c->direction)))
pos[child].y_offset = y_offset;
@@ -1518,14 +1529,13 @@
static void
reverse_cursive_minor_offset (hb_glyph_position_t *pos, unsigned int i, hb_direction_t direction, unsigned int new_parent)
{
- unsigned int j = pos[i].cursive_chain();
- if (likely (!j))
+ int chain = pos[i].attach_chain(), type = pos[i].attach_type();
+ if (likely (!chain || 0 == (type & ATTACH_TYPE_CURSIVE)))
return;
- int old_chain = j;
- pos[i].cursive_chain() = 0;
+ pos[i].attach_chain() = 0;
- j += i;
+ unsigned int j = (int) i + chain;
/* Stop if we see new parent in the chain. */
if (j == new_parent)
@@ -1538,17 +1548,19 @@
else
pos[j].x_offset = -pos[i].x_offset;
- pos[j].cursive_chain() = -old_chain;
+ pos[j].attach_chain() = -chain;
+ pos[j].attach_type() = type;
}
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))
+ int chain = pos[i].attach_chain(), type = pos[i].attach_type();
+ if (likely (!chain || 0 == (type & ATTACH_TYPE_CURSIVE)))
return;
- pos[i].cursive_chain() = 0;
- j += i;
+ pos[i].attach_chain() = 0;
+
+ unsigned int j = (int) i + chain;
fix_cursive_minor_offset (pos, j, direction);
@@ -1561,15 +1573,17 @@
static void
fix_mark_attachment (hb_glyph_position_t *pos, unsigned int i, hb_direction_t direction)
{
- unsigned int j = pos[i].attach_chain();
- if (likely (!j))
+ int chain = pos[i].attach_chain(), type = pos[i].attach_type();
+ if (likely (!chain || 0 == (type & ATTACH_TYPE_MARK)))
return;
- j += i;
+ unsigned int j = (int) i + chain;
+
pos[i].x_offset += pos[j].x_offset;
pos[i].y_offset += pos[j].y_offset;
+ assert (j < i);
if (HB_DIRECTION_IS_FORWARD (direction))
for (unsigned int k = j; k < i; k++) {
pos[i].x_offset -= pos[k].x_advance;
@@ -1589,7 +1603,7 @@
unsigned int count = buffer->len;
for (unsigned int i = 0; i < count; i++)
- buffer->pos[i].attach_chain() = buffer->pos[i].cursive_chain() = 0;
+ buffer->pos[i].attach_chain() = buffer->pos[i].attach_type() = 0;
}
void
@@ -1639,7 +1653,7 @@
#undef attach_chain
-#undef cursive_chain
+#undef attach_type
} /* namespace OT */
