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Diffstat (limited to 'gfx/harfbuzz/src/hb-ot-var-avar-table.hh')
| -rw-r--r-- | gfx/harfbuzz/src/hb-ot-var-avar-table.hh | 244 |
1 files changed, 244 insertions, 0 deletions
diff --git a/gfx/harfbuzz/src/hb-ot-var-avar-table.hh b/gfx/harfbuzz/src/hb-ot-var-avar-table.hh new file mode 100644 index 0000000000..3449b30499 --- /dev/null +++ b/gfx/harfbuzz/src/hb-ot-var-avar-table.hh @@ -0,0 +1,244 @@ +/* + * Copyright © 2017 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): Behdad Esfahbod + */ + +#ifndef HB_OT_VAR_AVAR_TABLE_HH +#define HB_OT_VAR_AVAR_TABLE_HH + +#include "hb-open-type.hh" +#include "hb-ot-var-common.hh" + + +/* + * avar -- Axis Variations + * https://docs.microsoft.com/en-us/typography/opentype/spec/avar + */ + +#define HB_OT_TAG_avar HB_TAG('a','v','a','r') + + +namespace OT { + + +/* "Spec": https://github.com/be-fonts/boring-expansion-spec/issues/14 */ +struct avarV2Tail +{ + friend struct avar; + + bool sanitize (hb_sanitize_context_t *c, + const void *base) const + { + TRACE_SANITIZE (this); + return_trace (varIdxMap.sanitize (c, base) && + varStore.sanitize (c, base)); + } + + protected: + Offset32To<DeltaSetIndexMap> varIdxMap; /* Offset from the beginning of 'avar' table. */ + Offset32To<VariationStore> varStore; /* Offset from the beginning of 'avar' table. */ + + public: + DEFINE_SIZE_STATIC (8); +}; + + +struct AxisValueMap +{ + bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + return_trace (c->check_struct (this)); + } + + public: + F2DOT14 coords[2]; +// F2DOT14 fromCoord; /* A normalized coordinate value obtained using +// * default normalization. */ +// F2DOT14 toCoord; /* The modified, normalized coordinate value. */ + + public: + DEFINE_SIZE_STATIC (4); +}; + +struct SegmentMaps : Array16Of<AxisValueMap> +{ + int map (int value, unsigned int from_offset = 0, unsigned int to_offset = 1) const + { +#define fromCoord coords[from_offset].to_int () +#define toCoord coords[to_offset].to_int () + /* The following special-cases are not part of OpenType, which requires + * that at least -1, 0, and +1 must be mapped. But we include these as + * part of a better error recovery scheme. */ + if (len < 2) + { + if (!len) + return value; + else /* len == 1*/ + return value - arrayZ[0].fromCoord + arrayZ[0].toCoord; + } + + if (value <= arrayZ[0].fromCoord) + return value - arrayZ[0].fromCoord + arrayZ[0].toCoord; + + unsigned int i; + unsigned int count = len - 1; + for (i = 1; i < count && value > arrayZ[i].fromCoord; i++) + ; + + if (value >= arrayZ[i].fromCoord) + return value - arrayZ[i].fromCoord + arrayZ[i].toCoord; + + if (unlikely (arrayZ[i-1].fromCoord == arrayZ[i].fromCoord)) + return arrayZ[i-1].toCoord; + + int denom = arrayZ[i].fromCoord - arrayZ[i-1].fromCoord; + return roundf (arrayZ[i-1].toCoord + ((float) (arrayZ[i].toCoord - arrayZ[i-1].toCoord) * + (value - arrayZ[i-1].fromCoord)) / denom); +#undef toCoord +#undef fromCoord + } + + int unmap (int value) const { return map (value, 1, 0); } + + public: + DEFINE_SIZE_ARRAY (2, *this); +}; + +struct avar +{ + static constexpr hb_tag_t tableTag = HB_OT_TAG_avar; + + bool has_data () const { return version.to_int (); } + + const SegmentMaps* get_segment_maps () const + { return &firstAxisSegmentMaps; } + + unsigned get_axis_count () const + { return axisCount; } + + bool sanitize (hb_sanitize_context_t *c) const + { + TRACE_SANITIZE (this); + if (!(version.sanitize (c) && + (version.major == 1 +#ifndef HB_NO_AVAR2 + || version.major == 2 +#endif + ) && + c->check_struct (this))) + return_trace (false); + + const SegmentMaps *map = &firstAxisSegmentMaps; + unsigned int count = axisCount; + for (unsigned int i = 0; i < count; i++) + { + if (unlikely (!map->sanitize (c))) + return_trace (false); + map = &StructAfter<SegmentMaps> (*map); + } + +#ifndef HB_NO_AVAR2 + if (version.major < 2) + return_trace (true); + + const auto &v2 = * (const avarV2Tail *) map; + if (unlikely (!v2.sanitize (c, this))) + return_trace (false); +#endif + + return_trace (true); + } + + void map_coords (int *coords, unsigned int coords_length) const + { + unsigned int count = hb_min (coords_length, axisCount); + + const SegmentMaps *map = &firstAxisSegmentMaps; + for (unsigned int i = 0; i < count; i++) + { + coords[i] = map->map (coords[i]); + map = &StructAfter<SegmentMaps> (*map); + } + +#ifndef HB_NO_AVAR2 + if (version.major < 2) + return; + + for (; count < axisCount; count++) + map = &StructAfter<SegmentMaps> (*map); + + const auto &v2 = * (const avarV2Tail *) map; + + const auto &varidx_map = this+v2.varIdxMap; + const auto &var_store = this+v2.varStore; + auto *var_store_cache = var_store.create_cache (); + + hb_vector_t<int> out; + out.alloc (coords_length); + for (unsigned i = 0; i < coords_length; i++) + { + int v = coords[i]; + uint32_t varidx = varidx_map.map (i); + float delta = var_store.get_delta (varidx, coords, coords_length, var_store_cache); + v += roundf (delta); + v = hb_clamp (v, -(1<<14), +(1<<14)); + out.push (v); + } + for (unsigned i = 0; i < coords_length; i++) + coords[i] = out[i]; + + OT::VariationStore::destroy_cache (var_store_cache); +#endif + } + + void unmap_coords (int *coords, unsigned int coords_length) const + { + unsigned int count = hb_min (coords_length, axisCount); + + const SegmentMaps *map = &firstAxisSegmentMaps; + for (unsigned int i = 0; i < count; i++) + { + coords[i] = map->unmap (coords[i]); + map = &StructAfter<SegmentMaps> (*map); + } + } + + protected: + FixedVersion<>version; /* Version of the avar table + * initially set to 0x00010000u */ + HBUINT16 reserved; /* This field is permanently reserved. Set to 0. */ + HBUINT16 axisCount; /* The number of variation axes in the font. This + * must be the same number as axisCount in the + * 'fvar' table. */ + SegmentMaps firstAxisSegmentMaps; + + public: + DEFINE_SIZE_MIN (8); +}; + +} /* namespace OT */ + + +#endif /* HB_OT_VAR_AVAR_TABLE_HH */ |