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#ifndef OT_LAYOUT_GPOS_VALUEFORMAT_HH
#define OT_LAYOUT_GPOS_VALUEFORMAT_HH
#include "../../../hb-ot-layout-gsubgpos.hh"
namespace OT {
namespace Layout {
namespace GPOS_impl {
typedef HBUINT16 Value;
struct ValueBase {}; // Dummy base class tag for OffsetTo<Value> bases.
typedef UnsizedArrayOf<Value> ValueRecord;
struct ValueFormat : HBUINT16
{
enum Flags {
xPlacement = 0x0001u, /* Includes horizontal adjustment for placement */
yPlacement = 0x0002u, /* Includes vertical adjustment for placement */
xAdvance = 0x0004u, /* Includes horizontal adjustment for advance */
yAdvance = 0x0008u, /* Includes vertical adjustment for advance */
xPlaDevice = 0x0010u, /* Includes horizontal Device table for placement */
yPlaDevice = 0x0020u, /* Includes vertical Device table for placement */
xAdvDevice = 0x0040u, /* Includes horizontal Device table for advance */
yAdvDevice = 0x0080u, /* Includes vertical Device table for advance */
ignored = 0x0F00u, /* Was used in TrueType Open for MM fonts */
reserved = 0xF000u, /* For future use */
devices = 0x00F0u /* Mask for having any Device table */
};
/* All fields are options. Only those available advance the value pointer. */
#if 0
HBINT16 xPlacement; /* Horizontal adjustment for
* placement--in design units */
HBINT16 yPlacement; /* Vertical adjustment for
* placement--in design units */
HBINT16 xAdvance; /* Horizontal adjustment for
* advance--in design units (only used
* for horizontal writing) */
HBINT16 yAdvance; /* Vertical adjustment for advance--in
* design units (only used for vertical
* writing) */
Offset16To<Device> xPlaDevice; /* Offset to Device table for
* horizontal placement--measured from
* beginning of PosTable (may be NULL) */
Offset16To<Device> yPlaDevice; /* Offset to Device table for vertical
* placement--measured from beginning
* of PosTable (may be NULL) */
Offset16To<Device> xAdvDevice; /* Offset to Device table for
* horizontal advance--measured from
* beginning of PosTable (may be NULL) */
Offset16To<Device> yAdvDevice; /* Offset to Device table for vertical
* advance--measured from beginning of
* PosTable (may be NULL) */
#endif
IntType& operator = (uint16_t i) { v = i; return *this; }
unsigned int get_len () const { return hb_popcount ((unsigned int) *this); }
unsigned int get_size () const { return get_len () * Value::static_size; }
hb_vector_t<unsigned> get_device_table_indices () const {
unsigned i = 0;
hb_vector_t<unsigned> result;
unsigned format = *this;
if (format & xPlacement) i++;
if (format & yPlacement) i++;
if (format & xAdvance) i++;
if (format & yAdvance) i++;
if (format & xPlaDevice) result.push (i++);
if (format & yPlaDevice) result.push (i++);
if (format & xAdvDevice) result.push (i++);
if (format & yAdvDevice) result.push (i++);
return result;
}
bool apply_value (hb_ot_apply_context_t *c,
const ValueBase *base,
const Value *values,
hb_glyph_position_t &glyph_pos) const
{
bool ret = false;
unsigned int format = *this;
if (!format) return ret;
hb_font_t *font = c->font;
bool horizontal =
#ifndef HB_NO_VERTICAL
HB_DIRECTION_IS_HORIZONTAL (c->direction)
#else
true
#endif
;
if (format & xPlacement) glyph_pos.x_offset += font->em_scale_x (get_short (values++, &ret));
if (format & yPlacement) glyph_pos.y_offset += font->em_scale_y (get_short (values++, &ret));
if (format & xAdvance) {
if (likely (horizontal)) glyph_pos.x_advance += font->em_scale_x (get_short (values, &ret));
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, &ret));
values++;
}
if (!has_device ()) return ret;
bool use_x_device = font->x_ppem || font->num_coords;
bool use_y_device = font->y_ppem || font->num_coords;
if (!use_x_device && !use_y_device) return ret;
const ItemVariationStore &store = c->var_store;
auto *cache = c->var_store_cache;
/* pixel -> fractional pixel */
if (format & xPlaDevice)
{
if (use_x_device) glyph_pos.x_offset += get_device (values, &ret, base, c->sanitizer).get_x_delta (font, store, cache);
values++;
}
if (format & yPlaDevice)
{
if (use_y_device) glyph_pos.y_offset += get_device (values, &ret, base, c->sanitizer).get_y_delta (font, store, cache);
values++;
}
if (format & xAdvDevice)
{
if (horizontal && use_x_device) glyph_pos.x_advance += get_device (values, &ret, base, c->sanitizer).get_x_delta (font, store, cache);
values++;
}
if (format & yAdvDevice)
{
/* y_advance values grow downward but font-space grows upward, hence negation */
if (!horizontal && use_y_device) glyph_pos.y_advance -= get_device (values, &ret, base, c->sanitizer).get_y_delta (font, store, cache);
values++;
}
return ret;
}
unsigned int get_effective_format (const Value *values, bool strip_hints, bool strip_empty, const ValueBase *base,
const hb_hashmap_t<unsigned, hb_pair_t<unsigned, int>> *varidx_delta_map) const
{
unsigned int format = *this;
for (unsigned flag = xPlacement; flag <= yAdvDevice; flag = flag << 1) {
if (format & flag)
{
if (strip_hints && flag >= xPlaDevice)
{
format = format & ~flag;
values++;
continue;
}
if (varidx_delta_map && flag >= xPlaDevice)
{
update_var_flag (values++, (Flags) flag, &format, base, varidx_delta_map);
continue;
}
/* do not strip empty when instancing, cause we don't know whether the new
* default value is 0 or not */
if (strip_empty) should_drop (*values, (Flags) flag, &format);
values++;
}
}
return format;
}
template<typename Iterator,
hb_requires (hb_is_iterator (Iterator))>
unsigned int get_effective_format (Iterator it, bool strip_hints, bool strip_empty, const ValueBase *base,
const hb_hashmap_t<unsigned, hb_pair_t<unsigned, int>> *varidx_delta_map) const {
unsigned int new_format = 0;
for (const hb_array_t<const Value>& values : it)
new_format = new_format | get_effective_format (&values, strip_hints, strip_empty, base, varidx_delta_map);
return new_format;
}
void copy_values (hb_serialize_context_t *c,
unsigned int new_format,
const ValueBase *base,
const Value *values,
const hb_hashmap_t<unsigned, hb_pair_t<unsigned, int>> *layout_variation_idx_delta_map) const
{
unsigned int format = *this;
if (!format) return;
HBINT16 *x_placement = nullptr, *y_placement = nullptr, *x_adv = nullptr, *y_adv = nullptr;
if (format & xPlacement) x_placement = copy_value (c, new_format, xPlacement, *values++);
if (format & yPlacement) y_placement = copy_value (c, new_format, yPlacement, *values++);
if (format & xAdvance) x_adv = copy_value (c, new_format, xAdvance, *values++);
if (format & yAdvance) y_adv = copy_value (c, new_format, yAdvance, *values++);
if (!has_device ())
return;
if (format & xPlaDevice)
{
add_delta_to_value (x_placement, base, values, layout_variation_idx_delta_map);
copy_device (c, base, values++, layout_variation_idx_delta_map, new_format, xPlaDevice);
}
if (format & yPlaDevice)
{
add_delta_to_value (y_placement, base, values, layout_variation_idx_delta_map);
copy_device (c, base, values++, layout_variation_idx_delta_map, new_format, yPlaDevice);
}
if (format & xAdvDevice)
{
add_delta_to_value (x_adv, base, values, layout_variation_idx_delta_map);
copy_device (c, base, values++, layout_variation_idx_delta_map, new_format, xAdvDevice);
}
if (format & yAdvDevice)
{
add_delta_to_value (y_adv, base, values, layout_variation_idx_delta_map);
copy_device (c, base, values++, layout_variation_idx_delta_map, new_format, yAdvDevice);
}
}
HBINT16* copy_value (hb_serialize_context_t *c,
unsigned int new_format,
Flags flag,
Value value) const
{
// Filter by new format.
if (!(new_format & flag)) return nullptr;
return reinterpret_cast<HBINT16 *> (c->copy (value));
}
void collect_variation_indices (hb_collect_variation_indices_context_t *c,
const ValueBase *base,
const hb_array_t<const Value>& values) const
{
unsigned format = *this;
unsigned i = 0;
if (format & xPlacement) i++;
if (format & yPlacement) i++;
if (format & xAdvance) i++;
if (format & yAdvance) i++;
if (format & xPlaDevice)
{
(base + get_device (&(values[i]))).collect_variation_indices (c);
i++;
}
if (format & ValueFormat::yPlaDevice)
{
(base + get_device (&(values[i]))).collect_variation_indices (c);
i++;
}
if (format & ValueFormat::xAdvDevice)
{
(base + get_device (&(values[i]))).collect_variation_indices (c);
i++;
}
if (format & ValueFormat::yAdvDevice)
{
(base + get_device (&(values[i]))).collect_variation_indices (c);
i++;
}
}
private:
bool sanitize_value_devices (hb_sanitize_context_t *c, const ValueBase *base, const Value *values) const
{
unsigned int format = *this;
if (format & xPlacement) values++;
if (format & yPlacement) values++;
if (format & xAdvance) values++;
if (format & yAdvance) values++;
if ((format & xPlaDevice) && !get_device (values++).sanitize (c, base)) return false;
if ((format & yPlaDevice) && !get_device (values++).sanitize (c, base)) return false;
if ((format & xAdvDevice) && !get_device (values++).sanitize (c, base)) return false;
if ((format & yAdvDevice) && !get_device (values++).sanitize (c, base)) return false;
return true;
}
static inline Offset16To<Device, ValueBase>& get_device (Value* value)
{
return *static_cast<Offset16To<Device, ValueBase> *> (value);
}
static inline const Offset16To<Device, ValueBase>& get_device (const Value* value)
{
return *static_cast<const Offset16To<Device, ValueBase> *> (value);
}
static inline const Device& get_device (const Value* value,
bool *worked,
const ValueBase *base,
hb_sanitize_context_t &c)
{
if (worked) *worked |= bool (*value);
auto &offset = *static_cast<const Offset16To<Device> *> (value);
if (unlikely (!offset.sanitize (&c, base)))
return Null(Device);
hb_barrier ();
return base + offset;
}
void add_delta_to_value (HBINT16 *value,
const ValueBase *base,
const Value *src_value,
const hb_hashmap_t<unsigned, hb_pair_t<unsigned, int>> *layout_variation_idx_delta_map) const
{
if (!value) return;
unsigned varidx = (base + get_device (src_value)).get_variation_index ();
hb_pair_t<unsigned, int> *varidx_delta;
if (!layout_variation_idx_delta_map->has (varidx, &varidx_delta)) return;
*value += hb_second (*varidx_delta);
}
bool copy_device (hb_serialize_context_t *c,
const ValueBase *base,
const Value *src_value,
const hb_hashmap_t<unsigned, hb_pair_t<unsigned, int>> *layout_variation_idx_delta_map,
unsigned int new_format, Flags flag) const
{
// Filter by new format.
if (!(new_format & flag)) return true;
Value *dst_value = c->copy (*src_value);
if (!dst_value) return false;
if (*dst_value == 0) return true;
*dst_value = 0;
c->push ();
if ((base + get_device (src_value)).copy (c, layout_variation_idx_delta_map))
{
c->add_link (*dst_value, c->pop_pack ());
return true;
}
else
{
c->pop_discard ();
return false;
}
}
static inline const HBINT16& get_short (const Value* value, bool *worked=nullptr)
{
if (worked) *worked |= bool (*value);
return *reinterpret_cast<const HBINT16 *> (value);
}
public:
bool has_device () const
{
unsigned int format = *this;
return (format & devices) != 0;
}
bool sanitize_value (hb_sanitize_context_t *c, const ValueBase *base, const Value *values) const
{
TRACE_SANITIZE (this);
if (unlikely (!c->check_range (values, get_size ()))) return_trace (false);
if (c->lazy_some_gpos)
return_trace (true);
return_trace (!has_device () || sanitize_value_devices (c, base, values));
}
bool sanitize_values (hb_sanitize_context_t *c, const ValueBase *base, const Value *values, unsigned int count) const
{
TRACE_SANITIZE (this);
unsigned size = get_size ();
if (!c->check_range (values, count, size)) return_trace (false);
if (c->lazy_some_gpos)
return_trace (true);
hb_barrier ();
return_trace (sanitize_values_stride_unsafe (c, base, values, count, size));
}
/* Just sanitize referenced Device tables. Doesn't check the values themselves. */
bool sanitize_values_stride_unsafe (hb_sanitize_context_t *c, const ValueBase *base, const Value *values, unsigned int count, unsigned int stride) const
{
TRACE_SANITIZE (this);
if (!has_device ()) return_trace (true);
for (unsigned int i = 0; i < count; i++) {
if (!sanitize_value_devices (c, base, values))
return_trace (false);
values = &StructAtOffset<const Value> (values, stride);
}
return_trace (true);
}
private:
void should_drop (Value value, Flags flag, unsigned int* format) const
{
if (value) return;
*format = *format & ~flag;
}
void update_var_flag (const Value* value, Flags flag,
unsigned int* format, const ValueBase *base,
const hb_hashmap_t<unsigned, hb_pair_t<unsigned, int>> *varidx_delta_map) const
{
if (*value)
{
unsigned varidx = (base + get_device (value)).get_variation_index ();
hb_pair_t<unsigned, int> *varidx_delta;
if (varidx_delta_map->has (varidx, &varidx_delta) &&
varidx_delta->first != HB_OT_LAYOUT_NO_VARIATIONS_INDEX)
return;
}
*format = *format & ~flag;
}
};
}
}
}
#endif // #ifndef OT_LAYOUT_GPOS_VALUEFORMAT_HH