michael@0: /*  GRAPHITE2 LICENSING
michael@0: 
michael@0:     Copyright 2010, SIL International
michael@0:     All rights reserved.
michael@0: 
michael@0:     This library is free software; you can redistribute it and/or modify
michael@0:     it under the terms of the GNU Lesser General Public License as published
michael@0:     by the Free Software Foundation; either version 2.1 of License, or
michael@0:     (at your option) any later version.
michael@0: 
michael@0:     This program is distributed in the hope that it will be useful,
michael@0:     but WITHOUT ANY WARRANTY; without even the implied warranty of
michael@0:     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
michael@0:     Lesser General Public License for more details.
michael@0: 
michael@0:     You should also have received a copy of the GNU Lesser General Public
michael@0:     License along with this library in the file named "LICENSE".
michael@0:     If not, write to the Free Software Foundation, 51 Franklin Street,
michael@0:     Suite 500, Boston, MA 02110-1335, USA or visit their web page on the
michael@0:     internet at http://www.fsf.org/licenses/lgpl.html.
michael@0: 
michael@0: Alternatively, the contents of this file may be used under the terms of the
michael@0: Mozilla Public License (http://mozilla.org/MPL) or the GNU General Public
michael@0: License, as published by the Free Software Foundation, either version 2
michael@0: of the License or (at your option) any later version.
michael@0: */
michael@0: 
michael@0: #include "inc/Main.h"
michael@0: #include "inc/CmapCache.h"
michael@0: #include "inc/Face.h"
michael@0: #include "inc/TtfTypes.h"
michael@0: #include "inc/TtfUtil.h"
michael@0: 
michael@0: 
michael@0: using namespace graphite2;
michael@0: 
michael@0: const void * bmp_subtable(const Face::Table & cmap)
michael@0: {
michael@0:     const void * stbl;
michael@0:     if (!cmap.size()) return 0;
michael@0:     if (TtfUtil::CheckCmapSubtable4(stbl = TtfUtil::FindCmapSubtable(cmap, 3, 1, cmap.size()))
michael@0:      || TtfUtil::CheckCmapSubtable4(stbl = TtfUtil::FindCmapSubtable(cmap, 0, 3, cmap.size()))
michael@0:      || TtfUtil::CheckCmapSubtable4(stbl = TtfUtil::FindCmapSubtable(cmap, 0, 2, cmap.size()))
michael@0:      || TtfUtil::CheckCmapSubtable4(stbl = TtfUtil::FindCmapSubtable(cmap, 0, 1, cmap.size()))
michael@0:      || TtfUtil::CheckCmapSubtable4(stbl = TtfUtil::FindCmapSubtable(cmap, 0, 0, cmap.size())))
michael@0:         return stbl;
michael@0:     return 0;
michael@0: }
michael@0: 
michael@0: const void * smp_subtable(const Face::Table & cmap)
michael@0: {
michael@0:     const void * stbl;
michael@0:     if (!cmap.size()) return 0;
michael@0:     if (TtfUtil::CheckCmapSubtable12(stbl = TtfUtil::FindCmapSubtable(cmap, 3, 10, cmap.size()))
michael@0:      || TtfUtil::CheckCmapSubtable12(stbl = TtfUtil::FindCmapSubtable(cmap, 0, 4, cmap.size())))
michael@0:         return stbl;
michael@0:     return 0;
michael@0: }
michael@0: 
michael@0: template <unsigned int (*NextCodePoint)(const void *, unsigned int, int *),
michael@0:           uint16 (*LookupCodePoint)(const void *, unsigned int, int)>
michael@0: bool cache_subtable(uint16 * blocks[], const void * cst, const unsigned int limit)
michael@0: {
michael@0:     int rangeKey = 0;
michael@0:     uint32          codePoint = NextCodePoint(cst, 0, &rangeKey),
michael@0:                     prevCodePoint = 0;
michael@0:     while (codePoint != limit)
michael@0:     {
michael@0:         unsigned int block = codePoint >> 8;
michael@0:         if (!blocks[block])
michael@0:         {
michael@0:             blocks[block] = grzeroalloc<uint16>(0x100);
michael@0:             if (!blocks[block])
michael@0:                 return false;
michael@0:         }
michael@0:         blocks[block][codePoint & 0xFF] = LookupCodePoint(cst, codePoint, rangeKey);
michael@0:         // prevent infinite loop
michael@0:         if (codePoint <= prevCodePoint)
michael@0:             codePoint = prevCodePoint + 1;
michael@0:         prevCodePoint = codePoint;
michael@0:         codePoint =  NextCodePoint(cst, codePoint, &rangeKey);
michael@0:     }
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: 
michael@0: CachedCmap::CachedCmap(const Face & face)
michael@0: : m_isBmpOnly(true),
michael@0:   m_blocks(0)
michael@0: {
michael@0:     const Face::Table cmap(face, Tag::cmap);
michael@0:     if (!cmap)  return;
michael@0: 
michael@0:     const void * bmp_cmap = bmp_subtable(cmap);
michael@0:     const void * smp_cmap = smp_subtable(cmap);
michael@0:     m_isBmpOnly = !smp_cmap;
michael@0: 
michael@0:     m_blocks = grzeroalloc<uint16 *>(m_isBmpOnly ? 0x100 : 0x1100);
michael@0:     if (m_blocks && smp_cmap)
michael@0:     {
michael@0:         if (!cache_subtable<TtfUtil::CmapSubtable12NextCodepoint, TtfUtil::CmapSubtable12Lookup>(m_blocks, smp_cmap, 0x10FFFF))
michael@0:             return;
michael@0:     }
michael@0: 
michael@0:     if (m_blocks && bmp_cmap)
michael@0:     {
michael@0:         if (!cache_subtable<TtfUtil::CmapSubtable4NextCodepoint, TtfUtil::CmapSubtable4Lookup>(m_blocks, bmp_cmap, 0xFFFF))
michael@0:             return;
michael@0:     }
michael@0: }
michael@0: 
michael@0: CachedCmap::~CachedCmap() throw()
michael@0: {
michael@0:     if (!m_blocks) return;
michael@0:     unsigned int numBlocks = (m_isBmpOnly)? 0x100 : 0x1100;
michael@0:     for (unsigned int i = 0; i < numBlocks; i++)
michael@0:         free(m_blocks[i]);
michael@0:     free(m_blocks);
michael@0: }
michael@0: 
michael@0: uint16 CachedCmap::operator [] (const uint32 usv) const throw()
michael@0: {
michael@0:     if ((m_isBmpOnly && usv > 0xFFFF) || (usv > 0x10FFFF))
michael@0:         return 0;
michael@0:     const uint32 block = 0xFFFF & (usv >> 8);
michael@0:     if (m_blocks[block])
michael@0:         return m_blocks[block][usv & 0xFF];
michael@0:     return 0;
michael@0: };
michael@0: 
michael@0: CachedCmap::operator bool() const throw()
michael@0: {
michael@0:     return m_blocks != 0;
michael@0: }
michael@0: 
michael@0: 
michael@0: DirectCmap::DirectCmap(const Face & face)
michael@0: : _cmap(face, Tag::cmap),
michael@0:   _smp(smp_subtable(_cmap)),
michael@0:   _bmp(bmp_subtable(_cmap))
michael@0: {
michael@0: }
michael@0: 
michael@0: uint16 DirectCmap::operator [] (const uint32 usv) const throw()
michael@0: {
michael@0:     return usv > 0xFFFF
michael@0:             ? (_smp ? TtfUtil::CmapSubtable12Lookup(_smp, usv, 0) : 0)
michael@0:             : TtfUtil::CmapSubtable4Lookup(_bmp, usv, 0);
michael@0: }
michael@0: 
michael@0: DirectCmap::operator bool () const throw()
michael@0: {
michael@0:     return _cmap && _bmp;
michael@0: }
michael@0: