src/hb-aat-layout-morx-table.hh | 64 +++++++++++++++++++++++++++++++++++++++-
1 file changed, 63 insertions(+), 1 deletion(-)
New commits:
commit dc8ed45292ce4e522c3bda03fd83873da7b6591e
Author: Behdad Esfahbod <beh...@behdad.org>
Date: Wed Sep 19 16:46:41 2018 -0400
[morx] Implement forward/backward processing
We reverse too many times. Can be optimized. But I doubt many fonts
use reverse lookups, so doesn't matter.
Other than not applying user features, this completes morx table
implementation.
diff --git a/src/hb-aat-layout-morx-table.hh b/src/hb-aat-layout-morx-table.hh
index 03bb4d53..0a2d62b5 100644
--- a/src/hb-aat-layout-morx-table.hh
+++ b/src/hb-aat-layout-morx-table.hh
@@ -836,6 +836,8 @@ struct Chain
unsigned int count = subtableCount;
for (unsigned int i = 0; i < count; i++)
{
+ bool reverse;
+
if (!(subtable->subFeatureFlags & flags))
goto skip;
@@ -844,11 +846,49 @@ struct Chain
bool (subtable->coverage & ChainSubtable::Vertical))
goto skip;
+ /* Buffer contents is always in logical direction. Determine if
+ * we need to reverse before applying this subtable. We reverse
+ * back after if we did reverse indeed.
+ *
+ * Quoting the spac:
+ * """
+ * Bits 28 and 30 of the coverage field control the order in which
+ * glyphs are processed when the subtable is run by the layout engine.
+ * Bit 28 is used to indicate if the glyph processing direction is
+ * the same as logical order or layout order. Bit 30 is used to
+ * indicate whether glyphs are processed forwards or backwards within
+ * that order.
+
+ Bit 30 Bit 28 Interpretation for Horizontal Text
+ 0 0 The subtable is processed in layout order
+ (the same order as the glyphs, which is
+ always left-to-right).
+ 1 0 The subtable is processed in reverse layout
order
+ (the order opposite that of the glyphs, which is
+ always right-to-left).
+ 0 1 The subtable is processed in logical order
+ (the same order as the characters, which may be
+ left-to-right or right-to-left).
+ 1 1 The subtable is processed in reverse logical
order
+ (the order opposite that of the characters,
which
+ may be right-to-left or left-to-right).
+ */
+ reverse = subtable->coverage & ChainSubtable::Logical ?
+ bool (subtable->coverage & ChainSubtable::Descending) :
+ bool (subtable->coverage & ChainSubtable::Descending) !=
+ HB_DIRECTION_IS_BACKWARD (c->buffer->props.direction);
+
if (!c->buffer->message (c->font, "start chain subtable %d",
c->lookup_index))
goto skip;
+ if (reverse)
+ c->buffer->reverse ();
+
subtable->dispatch (c);
+ if (reverse)
+ c->buffer->reverse ();
+
(void) c->buffer->message (c->font, "end chain subtable %d",
c->lookup_index);
skip:
commit 3bccd62196b5dff70d446c3fe053b1b47bb9c19e
Author: Behdad Esfahbod <beh...@behdad.org>
Date: Wed Sep 19 16:24:34 2018 -0400
[morx] Implement horiz-only/vert-only subtables
diff --git a/src/hb-aat-layout-morx-table.hh b/src/hb-aat-layout-morx-table.hh
index 03f31024..03bb4d53 100644
--- a/src/hb-aat-layout-morx-table.hh
+++ b/src/hb-aat-layout-morx-table.hh
@@ -743,8 +743,25 @@ struct ChainSubtable
friend struct Chain;
inline unsigned int get_size (void) const { return length; }
- inline unsigned int get_type (void) const { return coverage & 0xFF; }
+ inline unsigned int get_type (void) const { return coverage & SubtableType; }
+ enum Coverage
+ {
+ Vertical = 0x80000000, /* If set, this subtable will only be
applied
+ * to vertical text. If clear, this
subtable
+ * will only be applied to horizontal
text. */
+ Descending = 0x40000000, /* If set, this subtable will process
glyphs
+ * in descending order. If clear, it
will
+ * process the glyphs in ascending
order. */
+ AllDirections = 0x20000000, /* If set, this subtable will be
applied to
+ * both horizontal and vertical text
(i.e.
+ * the state of bit 0x80000000 is
ignored). */
+ Logical = 0x10000000, /* If set, this subtable will process
glyphs
+ * in logical order (or reverse logical
order,
+ * depending on the value of bit
0x80000000). */
+ Reserved = 0x0FFFFF00, /* Reserved, set to zero. */
+ SubtableType = 0x000000FF, /* Subtable type; see following table.
*/
+ };
enum Type
{
Rearrangement = 0,
@@ -822,6 +839,11 @@ struct Chain
if (!(subtable->subFeatureFlags & flags))
goto skip;
+ if (!(subtable->coverage & ChainSubtable::AllDirections) &&
+ HB_DIRECTION_IS_VERTICAL (c->buffer->props.direction) !=
+ bool (subtable->coverage & ChainSubtable::Vertical))
+ goto skip;
+
if (!c->buffer->message (c->font, "start chain subtable %d",
c->lookup_index))
goto skip;
_______________________________________________
HarfBuzz mailing list
HarfBuzz@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/harfbuzz
