[directwrite] Support feature ranges

Code copied from hb-uniscribe.cc and adapted to use DirectWrite types.
May be there is a better way to de-duplicate the code, though I'm not
exactly sure how or if it is worth it.
This commit is contained in:
Khaled Hosny 2021-06-20 18:59:13 +02:00 committed by Behdad Esfahbod
parent d2397d91f3
commit 14f220b761
1 changed files with 180 additions and 18 deletions

View File

@ -510,6 +510,44 @@ protected:
* shaper
*/
struct active_feature_t {
DWRITE_FONT_FEATURE fea;
unsigned int order;
HB_INTERNAL static int cmp (const void *pa, const void *pb) {
const active_feature_t *a = (const active_feature_t *) pa;
const active_feature_t *b = (const active_feature_t *) pb;
return a->fea.nameTag < b->fea.nameTag ? -1 : a->fea.nameTag > b->fea.nameTag ? 1 :
a->order < b->order ? -1 : a->order > b->order ? 1 :
a->fea.parameter < b->fea.parameter ? -1 : a->fea.parameter > b->fea.parameter ? 1 :
0;
}
bool operator== (const active_feature_t *f)
{ return cmp (this, f) == 0; }
};
struct feature_event_t {
unsigned int index;
bool start;
active_feature_t feature;
HB_INTERNAL static int cmp (const void *pa, const void *pb)
{
const feature_event_t *a = (const feature_event_t *) pa;
const feature_event_t *b = (const feature_event_t *) pb;
return a->index < b->index ? -1 : a->index > b->index ? 1 :
a->start < b->start ? -1 : a->start > b->start ? 1 :
active_feature_t::cmp (&a->feature, &b->feature);
}
};
struct range_record_t {
DWRITE_TYPOGRAPHIC_FEATURES features;
unsigned int index_first; /* == start */
unsigned int index_last; /* == end - 1 */
};
hb_bool_t
_hb_directwrite_shape (hb_shape_plan_t *shape_plan,
hb_font_t *font,
@ -568,8 +606,6 @@ _hb_directwrite_shape (hb_shape_plan_t *shape_plan,
log_clusters[chars_len++] = cluster; /* Surrogates. */
}
// TODO: Handle TEST_DISABLE_OPTIONAL_LIGATURES
DWRITE_READING_DIRECTION readingDirection;
readingDirection = buffer->props.direction ?
DWRITE_READING_DIRECTION_RIGHT_TO_LEFT :
@ -605,28 +641,157 @@ _hb_directwrite_shape (hb_shape_plan_t *shape_plan,
mbstowcs ((wchar_t*) localeName,
hb_language_to_string (buffer->props.language), 20);
// TODO: it does work but doesn't care about ranges
DWRITE_TYPOGRAPHIC_FEATURES typographic_features;
typographic_features.featureCount = num_features;
/*
* Set up features.
*/
hb_vector_t<DWRITE_FONT_FEATURE> feature_records;
hb_vector_t<range_record_t> range_records;
if (num_features)
{
typographic_features.features = new DWRITE_FONT_FEATURE[num_features];
for (unsigned int i = 0; i < num_features; ++i)
/* Sort features by start/end events. */
hb_vector_t<feature_event_t> feature_events;
for (unsigned int i = 0; i < num_features; i++)
{
typographic_features.features[i].nameTag = (DWRITE_FONT_FEATURE_TAG)
hb_uint32_swap (features[i].tag);
typographic_features.features[i].parameter = features[i].value;
active_feature_t feature;
feature.fea.nameTag = (DWRITE_FONT_FEATURE_TAG) hb_uint32_swap (features[i].tag);
feature.fea.parameter = features[i].value;
feature.order = i;
feature_event_t *event;
event = feature_events.push ();
event->index = features[i].start;
event->start = true;
event->feature = feature;
event = feature_events.push ();
event->index = features[i].end;
event->start = false;
event->feature = feature;
}
feature_events.qsort ();
/* Add a strategic final event. */
{
active_feature_t feature;
feature.fea.nameTag = (DWRITE_FONT_FEATURE_TAG) 0;
feature.fea.parameter = 0;
feature.order = num_features + 1;
feature_event_t *event = feature_events.push ();
event->index = 0; /* This value does magic. */
event->start = false;
event->feature = feature;
}
/* Scan events and save features for each range. */
hb_vector_t<active_feature_t> active_features;
unsigned int last_index = 0;
for (unsigned int i = 0; i < feature_events.length; i++)
{
feature_event_t *event = &feature_events[i];
if (event->index != last_index)
{
/* Save a snapshot of active features and the range. */
range_record_t *range = range_records.push ();
unsigned int offset = feature_records.length;
active_features.qsort ();
for (unsigned int j = 0; j < active_features.length; j++)
{
if (!j || active_features[j].fea.nameTag != feature_records[feature_records.length - 1].nameTag)
{
feature_records.push (active_features[j].fea);
}
else
{
/* Overrides value for existing feature. */
feature_records[feature_records.length - 1].parameter = active_features[j].fea.parameter;
}
}
/* Will convert to pointer after all is ready, since feature_records.array
* may move as we grow it. */
range->features.features = reinterpret_cast<DWRITE_FONT_FEATURE *> (offset);
range->features.featureCount = feature_records.length - offset;
range->index_first = last_index;
range->index_last = event->index - 1;
last_index = event->index;
}
if (event->start)
{
active_features.push (event->feature);
}
else
{
active_feature_t *feature = active_features.find (&event->feature);
if (feature)
active_features.remove (feature - active_features.arrayZ);
}
}
if (!range_records.length) /* No active feature found. */
num_features = 0;
/* Fixup the pointers. */
for (unsigned int i = 0; i < range_records.length; i++)
{
range_record_t *range = &range_records[i];
range->features.features = (DWRITE_FONT_FEATURE *) feature_records + reinterpret_cast<uintptr_t> (range->features.features);
}
}
const DWRITE_TYPOGRAPHIC_FEATURES* dwFeatures;
dwFeatures = (const DWRITE_TYPOGRAPHIC_FEATURES*) &typographic_features;
const uint32_t featureRangeLengths[] = { textLength };
hb_vector_t<DWRITE_TYPOGRAPHIC_FEATURES *> range_features;
hb_vector_t<uint32_t> range_char_counts;
if (num_features)
{
range_features.shrink (0);
range_char_counts.shrink (0);
range_record_t *last_range = &range_records[0];
for (unsigned int i = 0; i < textLength; i++)
{
range_record_t *range = last_range;
while (log_clusters[i] < range->index_first)
range--;
while (log_clusters[i] > range->index_last)
range++;
if (!range_features.length ||
&range->features != range_features[range_features.length - 1])
{
auto **typoFeatures = range_features.push ();
auto *c = range_char_counts.push ();
if (unlikely (!typoFeatures || !c))
{
range_features.shrink (0);
range_char_counts.shrink (0);
break;
}
*typoFeatures = &range->features;
*c = 1;
}
else
{
range_char_counts[range_char_counts.length - 1]++;
}
last_range = range;
}
}
const auto **dwFeatures = (const DWRITE_TYPOGRAPHIC_FEATURES**) range_features.arrayZ;
auto featureRanges = range_features.length;
const auto *featureRangeLengths = range_char_counts.arrayZ;
//
uint16_t* clusterMap;
clusterMap = new uint16_t[textLength];
DWRITE_SHAPING_TEXT_PROPERTIES* textProperties;
textProperties = new DWRITE_SHAPING_TEXT_PROPERTIES[textLength];
retry_getglyphs:
uint16_t* glyphIndices = new uint16_t[maxGlyphCount];
DWRITE_SHAPING_GLYPH_PROPERTIES* glyphProperties;
@ -634,7 +799,7 @@ retry_getglyphs:
hr = analyzer->GetGlyphs (textString, textLength, fontFace, false,
isRightToLeft, &runHead->mScript, localeName,
nullptr, &dwFeatures, featureRangeLengths, 1,
nullptr, dwFeatures, featureRangeLengths, featureRanges,
maxGlyphCount, clusterMap, textProperties,
glyphIndices, glyphProperties, &glyphCount);
@ -676,7 +841,7 @@ retry_getglyphs:
textLength, glyphIndices, glyphProperties,
glyphCount, fontFace, fontEmSize,
false, isRightToLeft, &runHead->mScript, localeName,
&dwFeatures, featureRangeLengths, 1,
dwFeatures, featureRangeLengths, featureRanges,
glyphAdvances, glyphOffsets);
if (FAILED (hr))
@ -742,9 +907,6 @@ retry_getglyphs:
delete [] glyphAdvances;
delete [] glyphOffsets;
if (num_features)
delete [] typographic_features.features;
/* Wow, done! */
return true;
}