* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*
- * Google Author(s): Behdad Esfahbod
+ * Google Author(s): Behdad Esfahbod, Roderick Sheeter
*/
#ifndef HB_OT_HMTX_TABLE_HH
#define HB_OT_HMTX_TABLE_HH
#include "hb-open-type-private.hh"
+#include "hb-ot-hhea-table.hh"
+#include "hb-ot-os2-table.hh"
+#include "hb-ot-var-hvar-table.hh"
namespace OT {
DEFINE_SIZE_STATIC (4);
};
+template <typename T, typename H>
struct hmtxvmtx
{
- static const hb_tag_t hmtxTag = HB_OT_TAG_hmtx;
- static const hb_tag_t vmtxTag = HB_OT_TAG_vmtx;
-
inline bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (true);
}
- public:
+
+ inline bool subset_update_header (hb_subset_plan_t *plan,
+ unsigned int num_hmetrics) const
+ {
+ hb_blob_t *src_blob = OT::Sanitizer<H> ().sanitize (plan->source->reference_table (H::tableTag));
+ hb_blob_t *dest_blob = hb_blob_copy_writable_or_fail(src_blob);
+ hb_blob_destroy (src_blob);
+
+ if (unlikely (!dest_blob)) {
+ return false;
+ }
+
+ unsigned int length;
+ H *table = (H *) hb_blob_get_data (dest_blob, &length);
+ table->numberOfLongMetrics.set (num_hmetrics);
+
+ bool result = hb_subset_plan_add_table (plan, H::tableTag, dest_blob);
+ hb_blob_destroy (dest_blob);
+
+ return result;
+ }
+
+ inline bool subset (hb_subset_plan_t *plan) const
+ {
+ typename T::accelerator_t _mtx;
+ _mtx.init (plan->source);
+
+ /* All the trailing glyphs with the same advance can use one LongMetric
+ * and just keep LSB */
+ hb_prealloced_array_t<hb_codepoint_t> &gids = plan->gids_to_retain_sorted;
+ unsigned int num_advances = gids.len;
+ unsigned int last_advance = _mtx.get_advance (gids[num_advances - 1]);
+ while (num_advances > 1
+ && last_advance == _mtx.get_advance (gids[num_advances - 2]))
+ {
+ num_advances--;
+ }
+
+ /* alloc the new table */
+ size_t dest_sz = num_advances * 4
+ + (gids.len - num_advances) * 2;
+ void *dest = (void *) malloc (dest_sz);
+ if (unlikely (!dest))
+ {
+ return false;
+ }
+ DEBUG_MSG(SUBSET, nullptr, "%c%c%c%c in src has %d advances, %d lsbs", HB_UNTAG(T::tableTag), _mtx.num_advances, _mtx.num_metrics - _mtx.num_advances);
+ DEBUG_MSG(SUBSET, nullptr, "%c%c%c%c in dest has %d advances, %d lsbs, %u bytes", HB_UNTAG(T::tableTag), num_advances, gids.len - num_advances, (unsigned int) dest_sz);
+
+ const char *source_table = hb_blob_get_data (_mtx.blob, nullptr);
+ // Copy everything over
+ LongMetric * old_metrics = (LongMetric *) source_table;
+ FWORD *lsbs = (FWORD *) (old_metrics + _mtx.num_advances);
+ char * dest_pos = (char *) dest;
+ for (unsigned int i = 0; i < gids.len; i++)
+ {
+ /* the last metric or the one for gids[i] */
+ LongMetric *src_metric = old_metrics + MIN ((hb_codepoint_t) _mtx.num_advances - 1, gids[i]);
+ if (gids[i] < _mtx.num_advances)
+ {
+ /* src is a LongMetric */
+ if (i < num_advances)
+ {
+ /* dest is a LongMetric, copy it */
+ *((LongMetric *) dest_pos) = *src_metric;
+ }
+ else
+ {
+ /* dest just lsb */
+ *((FWORD *) dest_pos) = src_metric->lsb;
+ }
+ }
+ else
+ {
+ FWORD src_lsb = *(lsbs + gids[i] - _mtx.num_advances);
+ if (i < num_advances)
+ {
+ /* dest needs a full LongMetric */
+ LongMetric *metric = (LongMetric *)dest_pos;
+ metric->advance = src_metric->advance;
+ metric->lsb = src_lsb;
+ }
+ else
+ {
+ /* dest just needs an lsb */
+ *((FWORD *) dest_pos) = src_lsb;
+ }
+ }
+ dest_pos += (i < num_advances ? 4 : 2);
+ }
+ _mtx.fini ();
+
+ // Amend header num hmetrics
+ if (unlikely (!subset_update_header (plan, num_advances)))
+ {
+ free (dest);
+ return false;
+ }
+
+ hb_blob_t *result = hb_blob_create ((const char *)dest,
+ dest_sz,
+ HB_MEMORY_MODE_READONLY,
+ dest,
+ free);
+ bool success = hb_subset_plan_add_table (plan, T::tableTag, result);
+ hb_blob_destroy (result);
+ return success;
+ }
+
+ struct accelerator_t
+ {
+ friend struct hmtxvmtx;
+
+ inline void init (hb_face_t *face,
+ unsigned int default_advance_ = 0)
+ {
+ default_advance = default_advance_ ? default_advance_ : hb_face_get_upem (face);
+
+ bool got_font_extents = false;
+ if (T::os2Tag)
+ {
+ hb_blob_t *os2_blob = Sanitizer<os2> ().sanitize (face->reference_table (T::os2Tag));
+ const os2 *os2_table = Sanitizer<os2>::lock_instance (os2_blob);
+#define USE_TYPO_METRICS (1u<<7)
+ if (0 != (os2_table->fsSelection & USE_TYPO_METRICS))
+ {
+ ascender = os2_table->sTypoAscender;
+ descender = os2_table->sTypoDescender;
+ line_gap = os2_table->sTypoLineGap;
+ got_font_extents = (ascender | descender) != 0;
+ }
+ hb_blob_destroy (os2_blob);
+ }
+
+ hb_blob_t *_hea_blob = Sanitizer<H> ().sanitize (face->reference_table (H::tableTag));
+ const H *_hea_table = Sanitizer<H>::lock_instance (_hea_blob);
+ num_advances = _hea_table->numberOfLongMetrics;
+ if (!got_font_extents)
+ {
+ ascender = _hea_table->ascender;
+ descender = _hea_table->descender;
+ line_gap = _hea_table->lineGap;
+ got_font_extents = (ascender | descender) != 0;
+ }
+ hb_blob_destroy (_hea_blob);
+
+ has_font_extents = got_font_extents;
+
+ blob = Sanitizer<hmtxvmtx> ().sanitize (face->reference_table (T::tableTag));
+
+ /* Cap num_metrics() and num_advances() based on table length. */
+ unsigned int len = hb_blob_get_length (blob);
+ if (unlikely (num_advances * 4 > len))
+ num_advances = len / 4;
+ num_metrics = num_advances + (len - 4 * num_advances) / 2;
+
+ /* We MUST set num_metrics to zero if num_advances is zero.
+ * Our get_advance() depends on that. */
+ if (unlikely (!num_advances))
+ {
+ num_metrics = num_advances = 0;
+ hb_blob_destroy (blob);
+ blob = hb_blob_get_empty ();
+ }
+ table = Sanitizer<hmtxvmtx>::lock_instance (blob);
+
+ var_blob = Sanitizer<HVARVVAR> ().sanitize (face->reference_table (T::variationsTag));
+ var_table = Sanitizer<HVARVVAR>::lock_instance (var_blob);
+ }
+
+ inline void fini (void)
+ {
+ hb_blob_destroy (blob);
+ hb_blob_destroy (var_blob);
+ }
+
+ inline unsigned int get_advance (hb_codepoint_t glyph) const
+ {
+ if (unlikely (glyph >= num_metrics))
+ {
+ /* If num_metrics is zero, it means we don't have the metrics table
+ * for this direction: return default advance. Otherwise, it means that the
+ * glyph index is out of bound: return zero. */
+ if (num_metrics)
+ return 0;
+ else
+ return default_advance;
+ }
+
+ return table->longMetric[MIN (glyph, (uint32_t) num_advances - 1)].advance;
+ }
+
+ inline unsigned int get_advance (hb_codepoint_t glyph,
+ hb_font_t *font) const
+ {
+ unsigned int advance = get_advance (glyph);
+ if (likely(glyph < num_metrics))
+ {
+ advance += (font->num_coords ? var_table->get_advance_var (glyph, font->coords, font->num_coords) : 0); // TODO Optimize?!
+ }
+ return advance;
+ }
+
+ public:
+ bool has_font_extents;
+ unsigned short ascender;
+ unsigned short descender;
+ unsigned short line_gap;
+
+ protected:
+ unsigned int num_metrics;
+ unsigned int num_advances;
+ unsigned int default_advance;
+
+ private:
+ const hmtxvmtx *table;
+ hb_blob_t *blob;
+ const HVARVVAR *var_table;
+ hb_blob_t *var_blob;
+ };
+
+ protected:
LongMetric longMetric[VAR]; /* Paired advance width and leading
* bearing values for each glyph. The
* value numOfHMetrics comes from
* be in the array, but that entry is
* required. The last entry applies to
* all subsequent glyphs. */
- FWORD leadingBearingX[VAR]; /* Here the advance is assumed
+/*FWORD leadingBearingX[VAR];*/ /* Here the advance is assumed
* to be the same as the advance
* for the last entry above. The
* number of entries in this array is
* font to vary the side bearing
* values for each glyph. */
public:
- DEFINE_SIZE_ARRAY2 (0, longMetric, leadingBearingX);
+ DEFINE_SIZE_ARRAY (0, longMetric);
};
-struct hmtx : hmtxvmtx {
+struct hmtx : hmtxvmtx<hmtx, hhea> {
static const hb_tag_t tableTag = HB_OT_TAG_hmtx;
+ static const hb_tag_t variationsTag = HB_OT_TAG_HVAR;
+ static const hb_tag_t os2Tag = HB_OT_TAG_os2;
};
-struct vmtx : hmtxvmtx {
+struct vmtx : hmtxvmtx<vmtx, vhea> {
static const hb_tag_t tableTag = HB_OT_TAG_vmtx;
+ static const hb_tag_t variationsTag = HB_OT_TAG_VVAR;
+ static const hb_tag_t os2Tag = HB_TAG_NONE;
};
} /* namespace OT */
projects / platform / upstream / harfbuzz.git / blobdiff