harfbuzz/src/hb-ot-color-colr-table.hh

279 lines
8.6 KiB
C++

/*
* Copyright © 2018 Ebrahim Byagowi
* Copyright © 2020 Google, Inc.
*
* This is part of HarfBuzz, a text shaping library.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*
* Google Author(s): Calder Kitagawa
*/
#ifndef HB_OT_COLOR_COLR_TABLE_HH
#define HB_OT_COLOR_COLR_TABLE_HH
#include "hb-open-type.hh"
/*
* COLR -- Color
* https://docs.microsoft.com/en-us/typography/opentype/spec/colr
*/
#define HB_OT_TAG_COLR HB_TAG('C','O','L','R')
namespace OT {
struct LayerRecord
{
operator hb_ot_color_layer_t () const { return {glyphId, colorIdx}; }
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (c->check_struct (this));
}
public:
HBGlyphID glyphId; /* Glyph ID of layer glyph */
Index colorIdx; /* Index value to use with a
* selected color palette.
* An index value of 0xFFFF
* is a special case indicating
* that the text foreground
* color (defined by a
* higher-level client) should
* be used and shall not be
* treated as actual index
* into CPAL ColorRecord array. */
public:
DEFINE_SIZE_STATIC (4);
};
struct BaseGlyphRecord
{
int cmp (hb_codepoint_t g) const
{ return g < glyphId ? -1 : g > glyphId ? 1 : 0; }
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (likely (c->check_struct (this)));
}
public:
HBGlyphID glyphId; /* Glyph ID of reference glyph */
HBUINT16 firstLayerIdx; /* Index (from beginning of
* the Layer Records) to the
* layer record. There will be
* numLayers consecutive entries
* for this base glyph. */
HBUINT16 numLayers; /* Number of color layers
* associated with this glyph */
public:
DEFINE_SIZE_STATIC (6);
};
struct COLR
{
static constexpr hb_tag_t tableTag = HB_OT_TAG_COLR;
bool has_data () const { return numBaseGlyphs; }
unsigned int get_glyph_layers (hb_codepoint_t glyph,
unsigned int start_offset,
unsigned int *count, /* IN/OUT. May be NULL. */
hb_ot_color_layer_t *layers /* OUT. May be NULL. */) const
{
const BaseGlyphRecord &record = (this+baseGlyphsZ).bsearch (numBaseGlyphs, glyph);
hb_array_t<const LayerRecord> all_layers = (this+layersZ).as_array (numLayers);
hb_array_t<const LayerRecord> glyph_layers = all_layers.sub_array (record.firstLayerIdx,
record.numLayers);
if (count)
{
+ glyph_layers.sub_array (start_offset, count)
| hb_sink (hb_array (layers, *count))
;
}
return glyph_layers.length;
}
struct accelerator_t
{
accelerator_t () {}
~accelerator_t () { fini (); }
void init (hb_face_t *face)
{ colr = hb_sanitize_context_t ().reference_table<COLR> (face); }
void fini () { this->colr.destroy (); }
bool is_valid () { return colr.get_blob ()->length; }
void closure_glyphs (hb_codepoint_t glyph,
hb_set_t *related_ids /* OUT */) const
{ colr->closure_glyphs (glyph, related_ids); }
private:
hb_blob_ptr_t<COLR> colr;
};
void closure_glyphs (hb_codepoint_t glyph,
hb_set_t *related_ids /* OUT */) const
{
const BaseGlyphRecord *record = get_base_glyph_record (glyph);
if (!record) return;
auto glyph_layers = (this+layersZ).as_array (numLayers).sub_array (record->firstLayerIdx,
record->numLayers);
if (!glyph_layers.length) return;
related_ids->add_array (&glyph_layers[0].glyphId, glyph_layers.length, LayerRecord::min_size);
}
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (likely (c->check_struct (this) &&
(this+baseGlyphsZ).sanitize (c, numBaseGlyphs) &&
(this+layersZ).sanitize (c, numLayers)));
}
template<typename BaseIterator, typename LayerIterator,
hb_requires (hb_is_iterator (BaseIterator)),
hb_requires (hb_is_iterator (LayerIterator))>
bool serialize (hb_serialize_context_t *c,
unsigned version,
BaseIterator base_it,
LayerIterator layer_it)
{
TRACE_SERIALIZE (this);
if (unlikely (base_it.len () != layer_it.len ()))
return_trace (false);
if (unlikely (!c->extend_min (this))) return_trace (false);
this->version = version;
numLayers = 0;
numBaseGlyphs = base_it.len ();
baseGlyphsZ = COLR::min_size;
layersZ = COLR::min_size + numBaseGlyphs * BaseGlyphRecord::min_size;
for (const hb_item_type<BaseIterator>& _ : + base_it.iter ())
{
auto* record = c->embed (_);
if (unlikely (!record)) return_trace (false);
record->firstLayerIdx = numLayers;
numLayers += record->numLayers;
}
for (const hb_item_type<LayerIterator>& _ : + layer_it.iter ())
_.as_array ().copy (c);
return_trace (true);
}
const BaseGlyphRecord* get_base_glyph_record (hb_codepoint_t gid) const
{
if ((unsigned int) gid == 0) // Ignore notdef.
return nullptr;
const BaseGlyphRecord* record = &(this+baseGlyphsZ).bsearch (numBaseGlyphs, (unsigned int) gid);
if ((record && (hb_codepoint_t) record->glyphId != gid))
record = nullptr;
return record;
}
bool subset (hb_subset_context_t *c) const
{
TRACE_SUBSET (this);
const hb_map_t &reverse_glyph_map = *c->plan->reverse_glyph_map;
auto base_it =
+ hb_range (c->plan->num_output_glyphs ())
| hb_map_retains_sorting ([&](hb_codepoint_t new_gid)
{
hb_codepoint_t old_gid = reverse_glyph_map.get (new_gid);
const BaseGlyphRecord* old_record = get_base_glyph_record (old_gid);
if (unlikely (!old_record))
return hb_pair_t<bool, BaseGlyphRecord> (false, Null (BaseGlyphRecord));
BaseGlyphRecord new_record;
new_record.glyphId = new_gid;
new_record.numLayers = old_record->numLayers;
return hb_pair_t<bool, BaseGlyphRecord> (true, new_record);
})
| hb_filter (hb_first)
| hb_map_retains_sorting (hb_second)
;
auto layer_it =
+ hb_range (c->plan->num_output_glyphs ())
| hb_map (reverse_glyph_map)
| hb_map_retains_sorting ([&](hb_codepoint_t old_gid)
{
const BaseGlyphRecord* old_record = get_base_glyph_record (old_gid);
hb_vector_t<LayerRecord> out_layers;
if (unlikely (!old_record ||
old_record->firstLayerIdx >= numLayers ||
old_record->firstLayerIdx + old_record->numLayers > numLayers))
return hb_pair_t<bool, hb_vector_t<LayerRecord>> (false, out_layers);
auto layers = (this+layersZ).as_array (numLayers).sub_array (old_record->firstLayerIdx,
old_record->numLayers);
out_layers.resize (layers.length);
for (unsigned int i = 0; i < layers.length; i++) {
out_layers[i] = layers[i];
hb_codepoint_t new_gid = 0;
if (unlikely (!c->plan->new_gid_for_old_gid (out_layers[i].glyphId, &new_gid)))
return hb_pair_t<bool, hb_vector_t<LayerRecord>> (false, out_layers);
out_layers[i].glyphId = new_gid;
}
return hb_pair_t<bool, hb_vector_t<LayerRecord>> (true, out_layers);
})
| hb_filter (hb_first)
| hb_map_retains_sorting (hb_second)
;
if (unlikely (!base_it || !layer_it || base_it.len () != layer_it.len ()))
return_trace (false);
COLR *colr_prime = c->serializer->start_embed<COLR> ();
return_trace (colr_prime->serialize (c->serializer, version, base_it, layer_it));
}
protected:
HBUINT16 version; /* Table version number (starts at 0). */
HBUINT16 numBaseGlyphs; /* Number of Base Glyph Records. */
LNNOffsetTo<SortedUnsizedArrayOf<BaseGlyphRecord>>
baseGlyphsZ; /* Offset to Base Glyph records. */
LNNOffsetTo<UnsizedArrayOf<LayerRecord>>
layersZ; /* Offset to Layer Records. */
HBUINT16 numLayers; /* Number of Layer Records. */
public:
DEFINE_SIZE_STATIC (14);
};
} /* namespace OT */
#endif /* HB_OT_COLOR_COLR_TABLE_HH */