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Diffstat (limited to 'gfx/graphite2/src/GlyphCache.cpp')
| -rw-r--r-- | gfx/graphite2/src/GlyphCache.cpp | 492 |
1 files changed, 492 insertions, 0 deletions
diff --git a/gfx/graphite2/src/GlyphCache.cpp b/gfx/graphite2/src/GlyphCache.cpp new file mode 100644 index 000000000..c4ab807b8 --- /dev/null +++ b/gfx/graphite2/src/GlyphCache.cpp @@ -0,0 +1,492 @@ +/* GRAPHITE2 LICENSING + + Copyright 2012, SIL International + All rights reserved. + + This library is free software; you can redistribute it and/or modify + it under the terms of the GNU Lesser General Public License as published + by the Free Software Foundation; either version 2.1 of License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should also have received a copy of the GNU Lesser General Public + License along with this library in the file named "LICENSE". + If not, write to the Free Software Foundation, 51 Franklin Street, + Suite 500, Boston, MA 02110-1335, USA or visit their web page on the + internet at http://www.fsf.org/licenses/lgpl.html. + +Alternatively, the contents of this file may be used under the terms of the +Mozilla Public License (http://mozilla.org/MPL) or the GNU General Public +License, as published by the Free Software Foundation, either version 2 +of the License or (at your option) any later version. +*/ +#include "graphite2/Font.h" + +#include "inc/Main.h" +#include "inc/Face.h" //for the tags +#include "inc/GlyphCache.h" +#include "inc/GlyphFace.h" +#include "inc/Endian.h" +#include "inc/bits.h" + +using namespace graphite2; + +namespace +{ + // Iterator over version 1 or 2 glat entries which consist of a series of + // +-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+ + // v1 |k|n|v1 |v2 |...|vN | or v2 | k | n |v1 |v2 |...|vN | + // +-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+ + // variable length structures. + + template<typename W> + class _glat_iterator : public std::iterator<std::input_iterator_tag, std::pair<sparse::key_type, sparse::mapped_type> > + { + unsigned short key() const { return be::peek<W>(_e) + _n; } + unsigned int run() const { return be::peek<W>(_e+sizeof(W)); } + void advance_entry() { _n = 0; _e = _v; be::skip<W>(_v,2); } + public: + _glat_iterator(const void * glat=0) : _e(reinterpret_cast<const byte *>(glat)), _v(_e+2*sizeof(W)), _n(0) {} + + _glat_iterator<W> & operator ++ () { + ++_n; be::skip<uint16>(_v); + if (_n == run()) advance_entry(); + return *this; + } + _glat_iterator<W> operator ++ (int) { _glat_iterator<W> tmp(*this); operator++(); return tmp; } + + // This is strictly a >= operator. A true == operator could be + // implemented that test for overlap but it would be more expensive a + // test. + bool operator == (const _glat_iterator<W> & rhs) { return _v >= rhs._e - 1; } + bool operator != (const _glat_iterator<W> & rhs) { return !operator==(rhs); } + + value_type operator * () const { + return value_type(key(), be::peek<uint16>(_v)); + } + + protected: + const byte * _e, * _v; + size_t _n; + }; + + typedef _glat_iterator<uint8> glat_iterator; + typedef _glat_iterator<uint16> glat2_iterator; +} + +const SlantBox SlantBox::empty = {0,0,0,0}; + + +class GlyphCache::Loader +{ +public: + Loader(const Face & face, const bool dumb_font); //return result indicates success. Do not use if failed. + + operator bool () const throw(); + unsigned short int units_per_em() const throw(); + unsigned short int num_glyphs() const throw(); + unsigned short int num_attrs() const throw(); + bool has_boxes() const throw(); + + const GlyphFace * read_glyph(unsigned short gid, GlyphFace &, int *numsubs) const throw(); + GlyphBox * read_box(uint16 gid, GlyphBox *curr, const GlyphFace & face) const throw(); + + CLASS_NEW_DELETE; +private: + Face::Table _head, + _hhea, + _hmtx, + _glyf, + _loca, + m_pGlat, + m_pGloc; + + bool _long_fmt; + bool _has_boxes; + unsigned short _num_glyphs_graphics, //i.e. boundary box and advance + _num_glyphs_attributes, + _num_attrs; // number of glyph attributes per glyph +}; + + + +GlyphCache::GlyphCache(const Face & face, const uint32 face_options) +: _glyph_loader(new Loader(face, bool(face_options & gr_face_dumbRendering))), + _glyphs(_glyph_loader && *_glyph_loader && _glyph_loader->num_glyphs() + ? grzeroalloc<const GlyphFace *>(_glyph_loader->num_glyphs()) : 0), + _boxes(_glyph_loader && _glyph_loader->has_boxes() && _glyph_loader->num_glyphs() + ? grzeroalloc<GlyphBox *>(_glyph_loader->num_glyphs()) : 0), + _num_glyphs(_glyphs ? _glyph_loader->num_glyphs() : 0), + _num_attrs(_glyphs ? _glyph_loader->num_attrs() : 0), + _upem(_glyphs ? _glyph_loader->units_per_em() : 0) +{ + if ((face_options & gr_face_preloadGlyphs) && _glyph_loader && _glyphs) + { + int numsubs = 0; + GlyphFace * const glyphs = new GlyphFace [_num_glyphs]; + if (!glyphs) + return; + + // The 0 glyph is definately required. + _glyphs[0] = _glyph_loader->read_glyph(0, glyphs[0], &numsubs); + + // glyphs[0] has the same address as the glyphs array just allocated, + // thus assigning the &glyphs[0] to _glyphs[0] means _glyphs[0] points + // to the entire array. + const GlyphFace * loaded = _glyphs[0]; + for (uint16 gid = 1; loaded && gid != _num_glyphs; ++gid) + _glyphs[gid] = loaded = _glyph_loader->read_glyph(gid, glyphs[gid], &numsubs); + + if (!loaded) + { + _glyphs[0] = 0; + delete [] glyphs; + } + else if (numsubs > 0 && _boxes) + { + GlyphBox * boxes = (GlyphBox *)gralloc<char>(_num_glyphs * sizeof(GlyphBox) + numsubs * 8 * sizeof(float)); + GlyphBox * currbox = boxes; + + for (uint16 gid = 0; currbox && gid != _num_glyphs; ++gid) + { + _boxes[gid] = currbox; + currbox = _glyph_loader->read_box(gid, currbox, *_glyphs[gid]); + } + if (!currbox) + { + free(boxes); + _boxes[0] = 0; + } + } + delete _glyph_loader; + _glyph_loader = 0; + } + + if (_glyphs && glyph(0) == 0) + { + free(_glyphs); + _glyphs = 0; + if (_boxes) + { + free(_boxes); + _boxes = 0; + } + _num_glyphs = _num_attrs = _upem = 0; + } +} + + +GlyphCache::~GlyphCache() +{ + if (_glyphs) + { + if (_glyph_loader) + { + const GlyphFace * * g = _glyphs; + for(unsigned short n = _num_glyphs; n; --n, ++g) + delete *g; + } + else + delete [] _glyphs[0]; + free(_glyphs); + } + if (_boxes) + { + if (_glyph_loader) + { + GlyphBox * * g = _boxes; + for (uint16 n = _num_glyphs; n; --n, ++g) + free(*g); + } + else + free(_boxes[0]); + free(_boxes); + } + delete _glyph_loader; +} + +const GlyphFace *GlyphCache::glyph(unsigned short glyphid) const //result may be changed by subsequent call with a different glyphid +{ + if (glyphid >= numGlyphs()) + return _glyphs[0]; + const GlyphFace * & p = _glyphs[glyphid]; + if (p == 0 && _glyph_loader) + { + int numsubs = 0; + GlyphFace * g = new GlyphFace(); + if (g) p = _glyph_loader->read_glyph(glyphid, *g, &numsubs); + if (!p) + { + delete g; + return *_glyphs; + } + if (_boxes) + { + _boxes[glyphid] = (GlyphBox *)gralloc<char>(sizeof(GlyphBox) + 8 * numsubs * sizeof(float)); + if (!_glyph_loader->read_box(glyphid, _boxes[glyphid], *_glyphs[glyphid])) + { + free(_boxes[glyphid]); + _boxes[glyphid] = 0; + } + } + } + return p; +} + + + +GlyphCache::Loader::Loader(const Face & face, const bool dumb_font) +: _head(face, Tag::head), + _hhea(face, Tag::hhea), + _hmtx(face, Tag::hmtx), + _glyf(face, Tag::glyf), + _loca(face, Tag::loca), + _long_fmt(false), + _has_boxes(false), + _num_glyphs_graphics(0), + _num_glyphs_attributes(0), + _num_attrs(0) +{ + if (!operator bool()) + return; + + const Face::Table maxp = Face::Table(face, Tag::maxp); + if (!maxp) { _head = Face::Table(); return; } + + _num_glyphs_graphics = TtfUtil::GlyphCount(maxp); + // This will fail if the number of glyphs is wildly out of range. + if (_glyf && TtfUtil::LocaLookup(_num_glyphs_graphics-1, _loca, _loca.size(), _head) == size_t(-2)) + { + _head = Face::Table(); + return; + } + + if (!dumb_font) + { + if ((m_pGlat = Face::Table(face, Tag::Glat, 0x00030000)) == NULL + || (m_pGloc = Face::Table(face, Tag::Gloc)) == NULL + || m_pGloc.size() < 8) + { + _head = Face::Table(); + return; + } + const byte * p = m_pGloc; + int version = be::read<uint32>(p); + const uint16 flags = be::read<uint16>(p); + _num_attrs = be::read<uint16>(p); + // We can accurately calculate the number of attributed glyphs by + // subtracting the length of the attribids array (numAttribs long if present) + // and dividing by either 2 or 4 depending on shor or lonf format + _long_fmt = flags & 1; + int tmpnumgattrs = (m_pGloc.size() + - (p - m_pGloc) + - sizeof(uint16)*(flags & 0x2 ? _num_attrs : 0)) + / (_long_fmt ? sizeof(uint32) : sizeof(uint16)) - 1; + + if (version >= 0x00020000 || tmpnumgattrs < 0 || tmpnumgattrs > 65535 + || _num_attrs == 0 || _num_attrs > 0x3000 // is this hard limit appropriate? + || _num_glyphs_graphics > tmpnumgattrs + || m_pGlat.size() < 4) + { + _head = Face::Table(); + return; + } + + _num_glyphs_attributes = static_cast<unsigned short>(tmpnumgattrs); + p = m_pGlat; + version = be::read<uint32>(p); + if (version >= 0x00040000 || (version >= 0x00030000 && m_pGlat.size() < 8)) // reject Glat tables that are too new + { + _head = Face::Table(); + return; + } + else if (version >= 0x00030000) + { + unsigned int glatflags = be::read<uint32>(p); + _has_boxes = glatflags & 1; + // delete this once the compiler is fixed + _has_boxes = true; + } + } +} + +inline +GlyphCache::Loader::operator bool () const throw() +{ + return _head && _hhea && _hmtx && !(bool(_glyf) != bool(_loca)); +} + +inline +unsigned short int GlyphCache::Loader::units_per_em() const throw() +{ + return _head ? TtfUtil::DesignUnits(_head) : 0; +} + +inline +unsigned short int GlyphCache::Loader::num_glyphs() const throw() +{ + return max(_num_glyphs_graphics, _num_glyphs_attributes); +} + +inline +unsigned short int GlyphCache::Loader::num_attrs() const throw() +{ + return _num_attrs; +} + +inline +bool GlyphCache::Loader::has_boxes () const throw() +{ + return _has_boxes; +} + +const GlyphFace * GlyphCache::Loader::read_glyph(unsigned short glyphid, GlyphFace & glyph, int *numsubs) const throw() +{ + Rect bbox; + Position advance; + + if (glyphid < _num_glyphs_graphics) + { + int nLsb; + unsigned int nAdvWid; + if (_glyf) + { + int xMin, yMin, xMax, yMax; + size_t locidx = TtfUtil::LocaLookup(glyphid, _loca, _loca.size(), _head); + void *pGlyph = TtfUtil::GlyfLookup(_glyf, locidx, _glyf.size()); + + if (pGlyph && TtfUtil::GlyfBox(pGlyph, xMin, yMin, xMax, yMax)) + { + if ((xMin > xMax) || (yMin > yMax)) + return 0; + bbox = Rect(Position(static_cast<float>(xMin), static_cast<float>(yMin)), + Position(static_cast<float>(xMax), static_cast<float>(yMax))); + } + } + if (TtfUtil::HorMetrics(glyphid, _hmtx, _hmtx.size(), _hhea, nLsb, nAdvWid)) + advance = Position(static_cast<float>(nAdvWid), 0); + } + + if (glyphid < _num_glyphs_attributes) + { + const byte * gloc = m_pGloc; + size_t glocs = 0, gloce = 0; + + be::skip<uint32>(gloc); + be::skip<uint16>(gloc,2); + if (_long_fmt) + { + if (8 + glyphid * sizeof(uint32) > m_pGloc.size()) + return 0; + be::skip<uint32>(gloc, glyphid); + glocs = be::read<uint32>(gloc); + gloce = be::peek<uint32>(gloc); + } + else + { + if (8 + glyphid * sizeof(uint16) > m_pGloc.size()) + return 0; + be::skip<uint16>(gloc, glyphid); + glocs = be::read<uint16>(gloc); + gloce = be::peek<uint16>(gloc); + } + + if (glocs >= m_pGlat.size() - 1 || gloce > m_pGlat.size()) + return 0; + + const uint32 glat_version = be::peek<uint32>(m_pGlat); + if (glat_version >= 0x00030000) + { + if (glocs >= gloce) + return 0; + const byte * p = m_pGlat + glocs; + uint16 bmap = be::read<uint16>(p); + int num = bit_set_count((uint32)bmap); + if (numsubs) *numsubs += num; + glocs += 6 + 8 * num; + if (glocs > gloce) + return 0; + } + if (glat_version < 0x00020000) + { + if (gloce - glocs < 2*sizeof(byte)+sizeof(uint16) + || gloce - glocs > _num_attrs*(2*sizeof(byte)+sizeof(uint16))) + return 0; + new (&glyph) GlyphFace(bbox, advance, glat_iterator(m_pGlat + glocs), glat_iterator(m_pGlat + gloce)); + } + else + { + if (gloce - glocs < 3*sizeof(uint16) // can a glyph have no attributes? why not? + || gloce - glocs > _num_attrs*3*sizeof(uint16) + || glocs > m_pGlat.size() - 2*sizeof(uint16)) + return 0; + new (&glyph) GlyphFace(bbox, advance, glat2_iterator(m_pGlat + glocs), glat2_iterator(m_pGlat + gloce)); + } + if (!glyph.attrs() || glyph.attrs().capacity() > _num_attrs) + return 0; + } + return &glyph; +} + +inline float scale_to(uint8 t, float zmin, float zmax) +{ + return (zmin + t * (zmax - zmin) / 255); +} + +Rect readbox(Rect &b, uint8 zxmin, uint8 zymin, uint8 zxmax, uint8 zymax) +{ + return Rect(Position(scale_to(zxmin, b.bl.x, b.tr.x), scale_to(zymin, b.bl.y, b.tr.y)), + Position(scale_to(zxmax, b.bl.x, b.tr.x), scale_to(zymax, b.bl.y, b.tr.y))); +} + +GlyphBox * GlyphCache::Loader::read_box(uint16 gid, GlyphBox *curr, const GlyphFace & glyph) const throw() +{ + if (gid >= _num_glyphs_attributes) return 0; + + const byte * gloc = m_pGloc; + size_t glocs = 0, gloce = 0; + + be::skip<uint32>(gloc); + be::skip<uint16>(gloc,2); + if (_long_fmt) + { + be::skip<uint32>(gloc, gid); + glocs = be::read<uint32>(gloc); + gloce = be::peek<uint32>(gloc); + } + else + { + be::skip<uint16>(gloc, gid); + glocs = be::read<uint16>(gloc); + gloce = be::peek<uint16>(gloc); + } + + if (gloce > m_pGlat.size() || glocs + 6 >= gloce) + return 0; + + const byte * p = m_pGlat + glocs; + uint16 bmap = be::read<uint16>(p); + int num = bit_set_count((uint32)bmap); + + Rect bbox = glyph.theBBox(); + Rect diamax(Position(bbox.bl.x + bbox.bl.y, bbox.bl.x - bbox.tr.y), + Position(bbox.tr.x + bbox.tr.y, bbox.tr.x - bbox.bl.y)); + Rect diabound = readbox(diamax, p[0], p[2], p[1], p[3]); + ::new (curr) GlyphBox(num, bmap, &diabound); + be::skip<uint8>(p, 4); + if (glocs + 6 + num * 8 >= gloce) + return 0; + + for (int i = 0; i < num * 2; ++i) + { + Rect box = readbox((i & 1) ? diamax : bbox, p[0], p[2], p[1], p[3]); + curr->addSubBox(i >> 1, i & 1, &box); + be::skip<uint8>(p, 4); + } + return (GlyphBox *)((char *)(curr) + sizeof(GlyphBox) + 2 * num * sizeof(Rect)); +} + |