summaryrefslogtreecommitdiffstats
path: root/gfx/graphite2/src/GlyphCache.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'gfx/graphite2/src/GlyphCache.cpp')
-rw-r--r--gfx/graphite2/src/GlyphCache.cpp492
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));
+}
+