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

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/*
* Copyright © 2016 Google, Inc.
* 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.
*
* Google Author(s): Sascha Brawer
*/
#ifndef HB_OT_COLOR_CPAL_TABLE_HH
#define HB_OT_COLOR_CPAL_TABLE_HH
#include "hb-open-type-private.hh"
/*
* Following parts to be moved to a public header.
*/
/**
* hb_ot_color_t:
* ARGB data type for holding color values.
*
* Since: REPLACEME
*/
typedef uint32_t hb_ot_color_t;
/**
* hb_ot_color_palette_flags_t:
* @HB_OT_COLOR_PALETTE_FLAG_DEFAULT: default indicating that there is nothing special to note about a color palette.
* @HB_OT_COLOR_PALETTE_FLAG_FOR_LIGHT_BACKGROUND: flag indicating that the color palette is suitable for rendering text on light background.
* @HB_OT_COLOR_PALETTE_FLAG_FOR_DARK_BACKGROUND: flag indicating that the color palette is suitable for rendering text on dark background.
*
* Since: REPLACEME
*/
typedef enum { /*< flags >*/
HB_OT_COLOR_PALETTE_FLAG_DEFAULT = 0x00000000u,
HB_OT_COLOR_PALETTE_FLAG_FOR_LIGHT_BACKGROUND = 0x00000001u,
HB_OT_COLOR_PALETTE_FLAG_FOR_DARK_BACKGROUND = 0x00000002u,
} hb_ot_color_palette_flags_t;
// HB_EXTERN unsigned int
// hb_ot_color_get_palette_count (hb_face_t *face);
// HB_EXTERN unsigned int
// hb_ot_color_get_palette_name_id (hb_face_t *face, unsigned int palette);
// HB_EXTERN hb_ot_color_palette_flags_t
// hb_ot_color_get_palette_flags (hb_face_t *face, unsigned int palette);
// HB_EXTERN unsigned int
// hb_ot_color_get_palette_colors (hb_face_t *face,
// unsigned int palette, /* default=0 */
// unsigned int start_offset,
// unsigned int *color_count /* IN/OUT */,
// hb_ot_color_t *colors /* OUT */);
/*
* CPAL -- Color Palette
* https://docs.microsoft.com/en-us/typography/opentype/spec/cpal
*/
#define HB_OT_TAG_CPAL HB_TAG('C','P','A','L')
namespace OT {
struct CPALV1Tail
{
friend struct CPAL;
inline bool
sanitize (hb_sanitize_context_t *c, const void *base, unsigned int palettes) const
{
TRACE_SANITIZE (this);
return_trace (c->check_struct (this) &&
(base+paletteFlagsZ).sanitize (c, palettes) &&
(base+paletteLabelZ).sanitize (c, palettes) &&
(base+paletteEntryLabelZ).sanitize (c, palettes));
}
private:
inline hb_ot_color_palette_flags_t
get_palette_flags (const void *base, unsigned int palette) const
{
// range checked at the CPAL caller
return (hb_ot_color_palette_flags_t) (uint32_t) (base+paletteFlagsZ)[palette];
}
inline unsigned int
get_palette_name_id (const void *base, unsigned int palette) const
{
// range checked at the CPAL caller
return (base+paletteLabelZ)[palette];
}
protected:
LOffsetTo<UnsizedArrayOf<HBUINT32> >
paletteFlagsZ; /* Offset from the beginning of CPAL table to
* the Palette Type Array. Set to 0 if no array
* is provided. */
LOffsetTo<UnsizedArrayOf<HBUINT16> >
paletteLabelZ; /* Offset from the beginning of CPAL table to
* the Palette Labels Array. Set to 0 if no
* array is provided. */
LOffsetTo<UnsizedArrayOf<HBUINT16> >
paletteEntryLabelZ; /* Offset from the beginning of CPAL table to
* the Palette Entry Label Array. Set to 0
* if no array is provided. */
public:
DEFINE_SIZE_STATIC (12);
};
typedef HBUINT32 BGRAColor;
struct CPAL
{
static const hb_tag_t tableTag = HB_OT_TAG_CPAL;
inline bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
if (unlikely (!(c->check_struct (this) && // it checks colorRecordIndices also
// see #get_size
(this+colorRecordsZ).sanitize (c, numColorRecords))))
return_trace (false);
// Check for indices sanity so no need for doing it runtime
for (unsigned int i = 0; i < numPalettes; ++i)
if (unlikely (colorRecordIndicesZ[i] + numPaletteEntries > numColorRecords))
return_trace (false);
// If version is zero, we are done here; otherwise we need to check tail also
if (version == 0)
return_trace (true);
const CPALV1Tail &v1 = StructAfter<CPALV1Tail> (*this);
return_trace (likely (v1.sanitize (c, this, numPalettes)));
}
inline unsigned int get_size (void) const
{
return min_size + numPalettes * sizeof (HBUINT16);
}
inline hb_ot_color_palette_flags_t get_palette_flags (unsigned int palette) const
{
if (unlikely (version == 0 || palette >= numPalettes))
return HB_OT_COLOR_PALETTE_FLAG_DEFAULT;
const CPALV1Tail& cpal1 = StructAfter<CPALV1Tail> (*this);
return cpal1.get_palette_flags (this, palette);
}
inline unsigned int get_palette_name_id (unsigned int palette) const
{
if (unlikely (version == 0 || palette >= numPalettes))
return 0xFFFF;
const CPALV1Tail& cpal1 = StructAfter<CPALV1Tail> (*this);
return cpal1.get_palette_name_id (this, palette);
}
inline unsigned int get_palette_count () const
{
return numPalettes;
}
inline hb_ot_color_t
get_color_record_argb (unsigned int color_index, unsigned int palette) const
{
if (unlikely (color_index >= numPaletteEntries || palette >= numPalettes))
return 0;
// No need for more range check as it is already done on #sanitize
const UnsizedArrayOf<BGRAColor>& color_records = this+colorRecordsZ;
return color_records[colorRecordIndicesZ[palette] + color_index];
}
protected:
HBUINT16 version; /* Table version number */
/* Version 0 */
HBUINT16 numPaletteEntries; /* Number of palette entries in each palette. */
HBUINT16 numPalettes; /* Number of palettes in the table. */
HBUINT16 numColorRecords; /* Total number of color records, combined for
* all palettes. */
LOffsetTo<UnsizedArrayOf<BGRAColor> >
colorRecordsZ; /* Offset from the beginning of CPAL table to
* the first ColorRecord. */
UnsizedArrayOf<HBUINT16>
colorRecordIndicesZ; /* Index of each palettes first color record in
* the combined color record array. */
/*CPALV1Tail v1;*/
public:
DEFINE_SIZE_ARRAY (12, colorRecordIndicesZ);
};
} /* namespace OT */
#endif /* HB_OT_COLOR_CPAL_TABLE_HH */