office-gobmx/vcl/source/text/ImplLayoutArgs.cxx
Jonathan Clark 0eedac9d66 tdf#161397 Fix incorrect glyphs for RTL font fallback
This change fixes an issue causing incorrect font fallback for certain
RTL grapheme clusters.

Change-Id: I6cff7f175b766d40c4faf204d1d65c8c366eb3e3
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/168410
Tested-by: Jenkins
Reviewed-by: Jonathan Clark <jonathan@libreoffice.org>
2024-06-06 12:09:06 +02:00

326 lines
10 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* This file incorporates work covered by the following license notice:
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed
* with this work for additional information regarding copyright
* ownership. The ASF licenses this file to you under the Apache
* License, Version 2.0 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.apache.org/licenses/LICENSE-2.0 .
*/
#include <ImplLayoutArgs.hxx>
#include <unicode/ubidi.h>
#include <unicode/uchar.h>
#include <algorithm>
#include <memory>
#include <utility>
namespace vcl::text
{
ImplLayoutArgs::ImplLayoutArgs(const OUString& rStr, int nMinCharPos, int nEndCharPos,
SalLayoutFlags nFlags, LanguageTag aLanguageTag,
vcl::text::TextLayoutCache const* const pLayoutCache)
: maLanguageTag(std::move(aLanguageTag))
, mnFlags(nFlags)
, mrStr(rStr)
, mnMinCharPos(nMinCharPos)
, mnEndCharPos(nEndCharPos)
, m_pTextLayoutCache(pLayoutCache)
, mnLayoutWidth(0)
, mnOrientation(0)
{
if (mnFlags & SalLayoutFlags::BiDiStrong)
{
// handle strong BiDi mode
// do not bother to BiDi analyze strong LTR/RTL
// TODO: can we assume these strings do not have unicode control chars?
// if not remove the control characters from the runs
bool bRTL(mnFlags & SalLayoutFlags::BiDiRtl);
AddRun(mnMinCharPos, mnEndCharPos, bRTL);
}
else
{
// handle weak BiDi mode
UBiDiLevel nLevel = (mnFlags & SalLayoutFlags::BiDiRtl) ? 1 : 0;
// prepare substring for BiDi analysis
// TODO: reuse allocated pParaBidi
UErrorCode rcI18n = U_ZERO_ERROR;
const int nLength = mnEndCharPos - mnMinCharPos;
UBiDi* pParaBidi = ubidi_openSized(nLength, 0, &rcI18n);
if (!pParaBidi)
return;
ubidi_setPara(pParaBidi, reinterpret_cast<const UChar*>(mrStr.getStr()) + mnMinCharPos,
nLength, nLevel, nullptr, &rcI18n);
// run BiDi algorithm
const int nRunCount = ubidi_countRuns(pParaBidi, &rcI18n);
for (int i = 0; i < nRunCount; ++i)
{
int32_t nMinPos, nRunLength;
const UBiDiDirection nDir = ubidi_getVisualRun(pParaBidi, i, &nMinPos, &nRunLength);
const int nPos0 = nMinPos + mnMinCharPos;
const int nPos1 = nPos0 + nRunLength;
const bool bRTL = (nDir == UBIDI_RTL);
AddRun(nPos0, nPos1, bRTL);
}
// cleanup BiDi engine
ubidi_close(pParaBidi);
}
// prepare calls to GetNextPos/GetNextRun
maRuns.ResetPos();
}
void ImplLayoutArgs::SetLayoutWidth(double nWidth) { mnLayoutWidth = nWidth; }
void ImplLayoutArgs::SetJustificationData(JustificationData stJustification)
{
mstJustification = std::move(stJustification);
}
void ImplLayoutArgs::SetOrientation(Degree10 nOrientation) { mnOrientation = nOrientation; }
void ImplLayoutArgs::ResetPos() { maRuns.ResetPos(); }
bool ImplLayoutArgs::GetNextPos(int* nCharPos, bool* bRTL)
{
return maRuns.GetNextPos(nCharPos, bRTL);
}
void ImplLayoutArgs::AddFallbackRun(int nMinRunPos, int nEndRunPos, bool bRTL)
{
maFallbackRuns.AddRun(nMinRunPos, nEndRunPos, bRTL);
}
bool ImplLayoutArgs::HasFallbackRun() const { return !maFallbackRuns.IsEmpty(); }
static bool IsControlChar(sal_UCS4 cChar)
{
// C0 control characters
if ((0x0001 <= cChar) && (cChar <= 0x001F))
return true;
// formatting characters
if ((0x200E <= cChar) && (cChar <= 0x200F))
return true;
if ((0x2028 <= cChar) && (cChar <= 0x202E))
return true;
// deprecated formatting characters
if ((0x206A <= cChar) && (cChar <= 0x206F))
return true;
if (0x2060 == cChar)
return true;
// byte order markers and invalid unicode
if ((cChar == 0xFEFF) || (cChar == 0xFFFE) || (cChar == 0xFFFF))
return true;
// drop null character too, broken documents may contain it (ofz34898-1.doc)
if (cChar == 0)
return true;
return false;
}
// add a run after splitting it up to get rid of control chars
void ImplLayoutArgs::AddRun(int nCharPos0, int nCharPos1, bool bRTL)
{
SAL_WARN_IF(nCharPos0 > nCharPos1, "vcl", "ImplLayoutArgs::AddRun() nCharPos0>=nCharPos1");
// remove control characters from runs by splitting them up
if (!bRTL)
{
for (int i = nCharPos0; i < nCharPos1; ++i)
if (IsControlChar(mrStr[i]))
{
// add run until control char
maRuns.AddRun(nCharPos0, i, bRTL);
nCharPos0 = i + 1;
}
}
else
{
for (int i = nCharPos1; --i >= nCharPos0;)
if (IsControlChar(mrStr[i]))
{
// add run until control char
maRuns.AddRun(i + 1, nCharPos1, bRTL);
nCharPos1 = i;
}
}
// add remainder of run
maRuns.AddRun(nCharPos0, nCharPos1, bRTL);
}
bool ImplLayoutArgs::PrepareFallback(const SalLayoutGlyphsImpl* pGlyphsImpl)
{
// Generate runs with pre-calculated glyph items instead maFallbackRuns.
if (pGlyphsImpl != nullptr)
{
maRuns.Clear();
maFallbackRuns.Clear();
for (auto const& aGlyphItem : *pGlyphsImpl)
{
for (int i = aGlyphItem.charPos(); i < aGlyphItem.charPos() + aGlyphItem.charCount();
++i)
maRuns.AddPos(i, aGlyphItem.IsRTLGlyph());
}
return !maRuns.IsEmpty();
}
// short circuit if no fallback is needed
if (maFallbackRuns.IsEmpty())
{
maRuns.Clear();
return false;
}
ImplLayoutRuns::PrepareFallbackRuns(&maRuns, &maFallbackRuns);
return true;
}
bool ImplLayoutArgs::GetNextRun(int* nMinRunPos, int* nEndRunPos, bool* bRTL)
{
bool bValid = maRuns.GetRun(nMinRunPos, nEndRunPos, bRTL);
maRuns.NextRun();
return bValid;
}
}
std::ostream& operator<<(std::ostream& s, vcl::text::ImplLayoutArgs const& rArgs)
{
#ifndef SAL_LOG_INFO
(void)rArgs;
#else
s << "ImplLayoutArgs{";
s << "Flags=";
if (rArgs.mnFlags == SalLayoutFlags::NONE)
s << 0;
else
{
bool need_or = false;
s << "{";
#define TEST(x) \
if (rArgs.mnFlags & SalLayoutFlags::x) \
{ \
if (need_or) \
s << "|"; \
s << #x; \
need_or = true; \
}
TEST(BiDiRtl);
TEST(BiDiStrong);
TEST(RightAlign);
TEST(DisableKerning);
TEST(KerningAsian);
TEST(Vertical);
TEST(DisableLigatures);
TEST(ForFallback);
#undef TEST
s << "}";
}
const int nLength = rArgs.mrStr.getLength();
s << ",Length=" << nLength;
s << ",MinCharPos=" << rArgs.mnMinCharPos;
s << ",EndCharPos=" << rArgs.mnEndCharPos;
s << ",Str=\"";
int lim = nLength;
if (lim > 10)
lim = 7;
for (int i = 0; i < lim; i++)
{
if (rArgs.mrStr[i] == '\n')
s << "\\n";
else if (rArgs.mrStr[i] < ' ' || (rArgs.mrStr[i] >= 0x7F && rArgs.mrStr[i] <= 0xFF))
s << "\\0x" << std::hex << std::setw(2) << std::setfill('0')
<< static_cast<int>(rArgs.mrStr[i]) << std::setfill(' ') << std::setw(1) << std::dec;
else if (rArgs.mrStr[i] < 0x7F)
s << static_cast<char>(rArgs.mrStr[i]);
else
s << "\\u" << std::hex << std::setw(4) << std::setfill('0')
<< static_cast<int>(rArgs.mrStr[i]) << std::setfill(' ') << std::setw(1) << std::dec;
}
if (nLength > lim)
s << "...";
s << "\"";
s << ",DXArray=";
if (!rArgs.mstJustification.empty())
{
s << "[";
int count = rArgs.mnEndCharPos - rArgs.mnMinCharPos;
lim = count;
if (lim > 10)
lim = 7;
for (int i = 0; i < lim; i++)
{
s << rArgs.mstJustification.GetTotalAdvance(rArgs.mnMinCharPos + i);
if (i < lim - 1)
s << ",";
}
if (count > lim)
{
if (count > lim + 1)
s << "...";
s << rArgs.mstJustification.GetTotalAdvance(rArgs.mnMinCharPos + count - 1);
}
s << "]";
}
else
s << "NULL";
s << ",KashidaArray=";
if (!rArgs.mstJustification.empty() && rArgs.mstJustification.ContainsKashidaPositions())
{
s << "[";
int count = rArgs.mnEndCharPos - rArgs.mnMinCharPos;
lim = count;
if (lim > 10)
lim = 7;
for (int i = 0; i < lim; i++)
{
s << rArgs.mstJustification.GetPositionHasKashida(rArgs.mnMinCharPos + i)
.value_or(false);
if (i < lim - 1)
s << ",";
}
if (count > lim)
{
if (count > lim + 1)
s << "...";
s << rArgs.mstJustification.GetPositionHasKashida(rArgs.mnMinCharPos + count - 1)
.value_or(false);
}
s << "]";
}
else
s << "NULL";
s << ",LayoutWidth=" << rArgs.mnLayoutWidth;
s << "}";
#endif
return s;
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */