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

145 lines
4.0 KiB
C++

/*
* Copyright © 2018 Ebrahim Byagowi
*
* 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.
*/
#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
{
friend struct COLR;
inline bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (c->check_struct (this));
}
protected:
GlyphID glyphid; /* Glyph ID of layer glyph */
HBUINT16 colorIdx; /* Index value to use with a selected color palette */
public:
DEFINE_SIZE_STATIC (4);
};
struct BaseGlyphRecord
{
friend struct COLR;
inline bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (likely (c->check_struct (this)));
}
inline int cmp (hb_codepoint_t g) const {
return g < glyphid ? -1 : g > glyphid ? 1 : 0;
}
protected:
GlyphID glyphid; /* Glyph ID of reference glyph */
HBUINT16 firstLayerIdx; /* Index to the layer record */
HBUINT16 numLayers; /* Number of color layers associated with this glyph */
public:
DEFINE_SIZE_STATIC (6);
};
static int compare_bgr (const void *pa, const void *pb)
{
const hb_codepoint_t *a = (const hb_codepoint_t *) pa;
const BaseGlyphRecord *b = (const BaseGlyphRecord *) pb;
return b->cmp (*a);
}
struct COLR
{
static const hb_tag_t tableTag = HB_OT_TAG_COLR;
inline 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)));
}
inline bool get_base_glyph_record (hb_codepoint_t glyph_id,
unsigned int *first_layer /* OUT */,
unsigned int *num_layers /* OUT */) const
{
const BaseGlyphRecord* record;
record = (BaseGlyphRecord *) bsearch (&glyph_id, &(this+baseGlyphsZ), numBaseGlyphs,
sizeof (BaseGlyphRecord), compare_bgr);
if (unlikely (!record))
return false;
*first_layer = record->firstLayerIdx;
*num_layers = record->numLayers;
return true;
}
inline bool get_layer_record (unsigned int record,
hb_codepoint_t *glyph_id /* OUT */,
unsigned int *palette_index /* OUT */) const
{
if (unlikely (record >= numLayers))
{
*glyph_id = 0;
*palette_index = 0xFFFF;
return false;
}
const LayerRecord &layer = (this+layersZ)[record];
*glyph_id = layer.glyphid;
*palette_index = layer.colorIdx;
return true;
}
protected:
HBUINT16 version; /* Table version number */
HBUINT16 numBaseGlyphs; /* Number of Base Glyph Records */
LOffsetTo<UnsizedArrayOf<BaseGlyphRecord> >
baseGlyphsZ; /* Offset to Base Glyph records. */
LOffsetTo<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 */