/* -*- 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 <sal/config.h>
#include <comphelper/scopeguard.hxx>
#include <unx/cairotextrender.hxx>
#include <unx/fc_fontoptions.hxx>
#include <unx/freetype_glyphcache.hxx>
#include <unx/gendata.hxx>
#include <headless/CairoCommon.hxx>
#include <vcl/svapp.hxx>
#include <sallayout.hxx>
#include <salinst.hxx>
#include <cairo.h>
#include <cairo-ft.h>
#if defined(CAIRO_HAS_SVG_SURFACE)
#include <cairo-svg.h>
#elif defined(CAIRO_HAS_PDF_SURFACE)
#include <cairo-pdf.h>
#endif
#include <deque>
namespace {
typedef struct FT_FaceRec_* FT_Face;
class CairoFontsCache : public CacheOwner
{
public:
struct CacheId
{
FT_Face maFace;
const FontConfigFontOptions *mpOptions;
bool mbEmbolden;
bool mbVerticalMetrics;
bool operator ==(const CacheId& rOther) const
{
return maFace == rOther.maFace &&
mpOptions == rOther.mpOptions &&
mbEmbolden == rOther.mbEmbolden &&
mbVerticalMetrics == rOther.mbVerticalMetrics;
}
};
private:
#if defined __cpp_lib_memory_resource
typedef std::pmr::vector< std::pair<cairo_font_face_t*, CacheId> > LRUFonts;
#else
typedef std::vector< std::pair<cairo_font_face_t*, CacheId> > LRUFonts;
#endif
LRUFonts maLRUFonts;
virtual OUString getCacheName() const override
{
return "CairoFontsCache";
}
virtual bool dropCaches() override
{
LRUFonts(maLRUFonts.get_allocator()).swap(maLRUFonts);
return true;
}
virtual void dumpState(rtl::OStringBuffer& rState) override
{
rState.append("\nCairoFontsCache:\t");
rState.append(static_cast<sal_Int32>(maLRUFonts.size()));
}
public:
CairoFontsCache()
#if defined __cpp_lib_memory_resource
: maLRUFonts(&CacheOwner::GetMemoryResource())
#else
: maLRUFonts()
#endif
{
}
void CacheFont(cairo_font_face_t* pFont, const CacheId &rId);
cairo_font_face_t* FindCachedFont(const CacheId &rId);
};
CairoFontsCache& getCairoFontsCache()
{
static CairoFontsCache aCache;
return aCache;
}
void CairoFontsCache::CacheFont(cairo_font_face_t* pFont, const CairoFontsCache::CacheId &rId)
{
maLRUFonts.push_back( std::pair<cairo_font_face_t*, CairoFontsCache::CacheId>(pFont, rId) );
if (maLRUFonts.size() > 8)
{
cairo_font_face_destroy(maLRUFonts.front().first);
maLRUFonts.erase(maLRUFonts.begin());
}
}
cairo_font_face_t* CairoFontsCache::FindCachedFont(const CairoFontsCache::CacheId &rId)
{
auto aI = std::find_if(maLRUFonts.rbegin(), maLRUFonts.rend(),
[&rId](const LRUFonts::value_type& rFont) { return rFont.second == rId; });
if (aI != maLRUFonts.rend())
return aI->first;
return nullptr;
}
}
namespace
{
bool hasRotation(int nRotation)
{
return nRotation != 0;
}
double toRadian(Degree10 nDegree10th)
{
return toRadians(3600_deg10 - nDegree10th);
}
cairo_t* syncCairoContext(cairo_t* cr)
{
//rhbz#1283420 tdf#117413 bodge to force a read from the underlying surface which has
//the side effect of making the mysterious xrender related problem go away
cairo_surface_t *target = cairo_get_target(cr);
if (cairo_surface_get_type(target) == CAIRO_SURFACE_TYPE_XLIB)
{
cairo_surface_t *throw_away = cairo_surface_create_similar(target, cairo_surface_get_content(target), 1, 1);
cairo_t *force_read_cr = cairo_create(throw_away);
cairo_set_source_surface(force_read_cr, target, 0, 0);
cairo_paint(force_read_cr);
cairo_destroy(force_read_cr);
cairo_surface_destroy(throw_away);
}
return cr;
}
}
#if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION)
extern "C"
{
__attribute__((weak)) void __lsan_disable();
__attribute__((weak)) void __lsan_enable();
}
#endif
namespace {
struct CairoFontOptions
{
// https://gitlab.freedesktop.org/cairo/cairo/-/merge_requests/235
// I don't want to have CAIRO_ROUND_GLYPH_POS_ON set in the cairo
// surfaces font_options, but that's private, so tricky to achieve
cairo_font_options_t* mpRoundGlyphPosOffOptions;
CairoFontOptions()
{
// https://gitlab.freedesktop.org/cairo/cairo/-/merge_requests/235
// I don't want to have CAIRO_ROUND_GLYPH_POS_ON set in the cairo surfaces
// font_options when trying subpixel rendering, but that's a private
// feature of cairo_font_options_t, so tricky to achieve. Hack this by
// getting the font options of a backend known to set this private feature
// to CAIRO_ROUND_GLYPH_POS_OFF and then set to defaults the public
// features and the result can be merged with new font options to set
// CAIRO_ROUND_GLYPH_POS_OFF in those
mpRoundGlyphPosOffOptions = cairo_font_options_create();
#if defined(CAIRO_HAS_SVG_SURFACE)
// svg, pdf and ps backends have CAIRO_ROUND_GLYPH_POS_OFF by default
cairo_surface_t* hack = cairo_svg_surface_create(nullptr, 1, 1);
#elif defined(CAIRO_HAS_PDF_SURFACE)
cairo_surface_t* hack = cairo_pdf_surface_create(nullptr, 1, 1);
#endif
cairo_surface_get_font_options(hack, mpRoundGlyphPosOffOptions);
cairo_surface_destroy(hack);
cairo_font_options_set_antialias(mpRoundGlyphPosOffOptions, CAIRO_ANTIALIAS_DEFAULT);
cairo_font_options_set_subpixel_order(mpRoundGlyphPosOffOptions, CAIRO_SUBPIXEL_ORDER_DEFAULT);
cairo_font_options_set_hint_style(mpRoundGlyphPosOffOptions, CAIRO_HINT_STYLE_DEFAULT);
cairo_font_options_set_hint_metrics(mpRoundGlyphPosOffOptions, CAIRO_HINT_METRICS_DEFAULT);
}
~CairoFontOptions()
{
cairo_font_options_destroy(mpRoundGlyphPosOffOptions);
}
static const cairo_font_options_t *get()
{
static CairoFontOptions opts;
return opts.mpRoundGlyphPosOffOptions;
}
};
}
CairoTextRender::CairoTextRender(CairoCommon& rCairoCommon)
: mrCairoCommon(rCairoCommon)
{
}
CairoTextRender::~CairoTextRender()
{
}
static void ApplyFont(cairo_t* cr, const CairoFontsCache::CacheId& rId, double nWidth, double nHeight, int nGlyphRotation,
const GenericSalLayout& rLayout)
{
CairoFontsCache& rCache = getCairoFontsCache();
cairo_font_face_t* font_face = rCache.FindCachedFont(rId);
if (!font_face)
{
const FontConfigFontOptions *pOptions = rId.mpOptions;
FcPattern *pPattern = pOptions->GetPattern();
font_face = cairo_ft_font_face_create_for_pattern(pPattern);
rCache.CacheFont(font_face, rId);
}
cairo_set_font_face(cr, font_face);
cairo_set_font_size(cr, nHeight);
cairo_matrix_t m;
cairo_matrix_init_identity(&m);
if (rLayout.GetOrientation())
cairo_matrix_rotate(&m, toRadian(rLayout.GetOrientation()));
cairo_matrix_scale(&m, nWidth, nHeight);
if (nGlyphRotation)
cairo_matrix_rotate(&m, toRadian(Degree10(nGlyphRotation * 900)));
const LogicalFontInstance& rInstance = rLayout.GetFont();
if (rInstance.NeedsArtificialItalic())
{
cairo_matrix_t shear;
cairo_matrix_init_identity(&shear);
shear.xy = -shear.xx * ARTIFICIAL_ITALIC_SKEW;
cairo_matrix_multiply(&m, &shear, &m);
}
cairo_set_font_matrix(cr, &m);
}
static CairoFontsCache::CacheId makeCacheId(const GenericSalLayout& rLayout)
{
const FreetypeFontInstance& rInstance = static_cast<FreetypeFontInstance&>(rLayout.GetFont());
const FreetypeFont& rFont = rInstance.GetFreetypeFont();
FT_Face aFace = rFont.GetFtFace();
CairoFontsCache::CacheId aId;
aId.maFace = aFace;
aId.mpOptions = rFont.GetFontOptions();
aId.mbEmbolden = rInstance.NeedsArtificialBold();
aId.mbVerticalMetrics = false;
return aId;
}
void CairoTextRender::DrawTextLayout(const GenericSalLayout& rLayout, const SalGraphics& rGraphics)
{
/*
* It might be ideal to cache surface and cairo context between calls and
* only destroy it when the drawable changes, but to do that we need to at
* least change the SalFrame etc impls to dtor the SalGraphics *before* the
* destruction of the windows they reference
*/
cairo_t *cr = syncCairoContext(getCairoContext());
if (!cr)
{
SAL_WARN("vcl", "no cairo context for text");
return;
}
comphelper::ScopeGuard releaseContext([this, cr]() { releaseCairoContext(cr); });
// void CairoCommon::clipRegion(cairo_t* cr) { CairoCommon::clipRegion(cr, m_aClipRegion); }
ImplDrawTextLayout(cr, mnTextColor, rLayout, &mrCairoCommon, rGraphics.getAntiAlias());
}
void CairoTextRender::ImplDrawTextLayout(cairo_t* cr, const Color& rTextColor, const GenericSalLayout& rLayout, CairoCommon* pCairoCommon, bool bAntiAlias)
{
const LogicalFontInstance& rInstance = rLayout.GetFont();
const bool bSubpixelPositioning = rLayout.GetSubpixelPositioning();
std::vector<cairo_glyph_t> cairo_glyphs;
std::vector<int> glyph_extrarotation;
cairo_glyphs.reserve( 256 );
double nSnapToSubPixelDiff = 0.0;
double nXScale, nYScale;
dl_cairo_surface_get_device_scale(cairo_get_target(cr), &nXScale, &nYScale);
basegfx::B2DPoint aPos;
const GlyphItem* pGlyph;
const GlyphItem* pPrevGlyph = nullptr;
int nStart = 0;
while (rLayout.GetNextGlyph(&pGlyph, aPos, nStart))
{
cairo_glyph_t aGlyph;
aGlyph.index = pGlyph->glyphId();
aGlyph.x = aPos.getX();
aGlyph.y = aPos.getY();
const bool bVertical = pGlyph->IsVertical();
glyph_extrarotation.push_back(bVertical ? 1 : 0);
if (bSubpixelPositioning)
{
// tdf#150507 like skia, even when subpixel rendering pixel, snap y
if (!bVertical)
aGlyph.y = std::floor(aGlyph.y + 0.5);
else
aGlyph.x = std::floor(aGlyph.x + 0.5);
// tdf#152094 snap to 1/4 of a pixel after a run of whitespace,
// probably a little dubious, but maybe worth a shot for lodpi
double& rGlyphDimension = !bVertical ? aGlyph.x : aGlyph.y;
const int nSubPixels = 4 * (!bVertical ? nXScale : nYScale);
if (pGlyph->IsSpacing())
nSnapToSubPixelDiff = 0;
else if (pPrevGlyph && pPrevGlyph->IsSpacing())
{
double nSnapToSubPixel = std::floor(rGlyphDimension * nSubPixels) / nSubPixels;
nSnapToSubPixelDiff = rGlyphDimension - nSnapToSubPixel;
rGlyphDimension = nSnapToSubPixel;
}
else
rGlyphDimension -= nSnapToSubPixelDiff;
pPrevGlyph = pGlyph;
}
cairo_glyphs.push_back(aGlyph);
}
const size_t nGlyphs = cairo_glyphs.size();
if (!nGlyphs)
return;
const vcl::font::FontSelectPattern& rFSD = rInstance.GetFontSelectPattern();
double nHeight = rFSD.mnHeight;
double nWidth = rFSD.mnWidth ? rFSD.mnWidth : nHeight;
if (nWidth == 0 || nHeight == 0)
return;
if (nHeight > SAL_MAX_UINT16)
{
// as seen with freetype 2.11.0, so cairo surface status is "fail"
// ("error occurred in libfreetype") and no further operations are
// executed, so this error then leads to later leaks
SAL_WARN("vcl", "rendering text would fail with height: " << nHeight);
return;
}
#if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION)
if (nHeight > 7000)
{
SAL_WARN("vcl", "rendering text would use > 2G Memory: " << nHeight);
return;
}
if (nWidth > 2000)
{
SAL_WARN("vcl", "rendering text would use > 2G Memory: " << nWidth);
return;
}
#endif
if (nullptr != pCairoCommon)
pCairoCommon->clipRegion(cr);
cairo_set_source_rgba(cr,
rTextColor.GetRed()/255.0,
rTextColor.GetGreen()/255.0,
rTextColor.GetBlue()/255.0,
rTextColor.GetAlpha()/255.0);
int nRatio = nWidth * 10 / nHeight;
// tdf#132112 excessive stretch of underbrace and overbrace can trigger freetype into an error, which propagates to cairo
// and once a cairo surface is in an error state, that cannot be cleared and all subsequent drawing fails, so bodge that
// with a high degree of stretch we draw the brace without stretch to a temp surface and stretch that to give a far
// poorer visual result, but one that can be rendered.
if (nGlyphs == 1 && nRatio > 100 && (cairo_glyphs[0].index == 974 || cairo_glyphs[0].index == 975) &&
rFSD.maTargetName == "OpenSymbol" && !glyph_extrarotation.back() && !rLayout.GetOrientation())
{
CairoFontsCache::CacheId aId = makeCacheId(rLayout);
ApplyFont(cr, aId, nWidth, nHeight, 0, rLayout);
cairo_text_extents_t stretched_extents;
cairo_glyph_extents(cr, cairo_glyphs.data(), nGlyphs, &stretched_extents);
ApplyFont(cr, aId, nHeight, nHeight, 0, rLayout);
cairo_text_extents_t unstretched_extents;
cairo_glyph_extents(cr, cairo_glyphs.data(), nGlyphs, &unstretched_extents);
cairo_surface_t *target = cairo_get_target(cr);
cairo_surface_t *temp_surface = cairo_surface_create_similar(target, cairo_surface_get_content(target),
unstretched_extents.width, unstretched_extents.height);
cairo_t *temp_cr = cairo_create(temp_surface);
cairo_glyph_t glyph;
glyph.x = -unstretched_extents.x_bearing;
glyph.y = -unstretched_extents.y_bearing;
glyph.index = cairo_glyphs[0].index;
ApplyFont(temp_cr, aId, nHeight, nHeight, 0, rLayout);
cairo_set_source_rgb(temp_cr,
rTextColor.GetRed()/255.0,
rTextColor.GetGreen()/255.0,
rTextColor.GetBlue()/255.0);
cairo_show_glyphs(temp_cr, &glyph, 1);
cairo_destroy(temp_cr);
cairo_set_source_surface(cr, temp_surface, cairo_glyphs[0].x, cairo_glyphs[0].y + stretched_extents.y_bearing);
cairo_pattern_t* sourcepattern = cairo_get_source(cr);
cairo_matrix_t matrix;
cairo_pattern_get_matrix(sourcepattern, &matrix);
cairo_matrix_scale(&matrix, unstretched_extents.width / stretched_extents.width, 1);
cairo_pattern_set_matrix(sourcepattern, &matrix);
cairo_rectangle(cr, cairo_glyphs[0].x, cairo_glyphs[0].y + stretched_extents.y_bearing, stretched_extents.width, stretched_extents.height);
cairo_fill(cr);
cairo_surface_destroy(temp_surface);
return;
}
if (nRatio >= 5120)
{
// as seen with freetype 2.12.1, so cairo surface status is "fail"
SAL_WARN("vcl", "rendering text would fail with stretch of: " << nRatio / 10.0);
return;
}
#if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION)
if (__lsan_disable)
__lsan_disable();
#endif
const StyleSettings& rStyleSettings = Application::GetSettings().GetStyleSettings();
const bool bDisableAA = !rStyleSettings.GetUseFontAAFromSystem() && !bAntiAlias;
static bool bAllowDefaultHinting = getenv("SAL_ALLOW_DEFAULT_HINTING") != nullptr;
const cairo_font_options_t* pFontOptions = GetSalInstance()->GetCairoFontOptions();
if (pFontOptions || bDisableAA || bSubpixelPositioning)
{
cairo_hint_style_t eHintStyle = pFontOptions ? cairo_font_options_get_hint_style(pFontOptions) : CAIRO_HINT_STYLE_DEFAULT;
bool bAllowedHintStyle = !bSubpixelPositioning || bAllowDefaultHinting || (eHintStyle == CAIRO_HINT_STYLE_NONE || eHintStyle == CAIRO_HINT_STYLE_SLIGHT);
if (bDisableAA || !bAllowedHintStyle || bSubpixelPositioning)
{
// Disable font AA in case global AA setting is supposed to affect
// font rendering (not the default) and AA is disabled.
cairo_font_options_t* pOptions = pFontOptions ? cairo_font_options_copy(pFontOptions) : cairo_font_options_create();
if (bDisableAA)
cairo_font_options_set_antialias(pOptions, CAIRO_ANTIALIAS_NONE);
if (!bAllowedHintStyle)
cairo_font_options_set_hint_style(pOptions, CAIRO_HINT_STYLE_SLIGHT);
if (bSubpixelPositioning)
{
// Disable private CAIRO_ROUND_GLYPH_POS_ON by merging with
// font options known to have CAIRO_ROUND_GLYPH_POS_OFF
cairo_font_options_merge(pOptions, CairoFontOptions::get());
// a) tdf#153699 skip this with cairo 1.17.8 as it has a problem
// See: https://gitlab.freedesktop.org/cairo/cairo/-/issues/643
// b) tdf#152675 a similar report for cairo: 1.16.0-4ubuntu1,
// assume that everything <= 1.17.8 is unsafe to disable this
if (cairo_version() > CAIRO_VERSION_ENCODE(1, 17, 8))
cairo_font_options_set_hint_metrics(pOptions, CAIRO_HINT_METRICS_OFF);
}
cairo_set_font_options(cr, pOptions);
cairo_font_options_destroy(pOptions);
}
else if (pFontOptions)
cairo_set_font_options(cr, pFontOptions);
}
CairoFontsCache::CacheId aId = makeCacheId(rLayout);
std::vector<int>::const_iterator aEnd = glyph_extrarotation.end();
std::vector<int>::const_iterator aStart = glyph_extrarotation.begin();
std::vector<int>::const_iterator aI = aStart;
while (aI != aEnd)
{
int nGlyphRotation = *aI;
std::vector<int>::const_iterator aNext = nGlyphRotation?(aI+1):std::find_if(aI+1, aEnd, hasRotation);
size_t nStartIndex = std::distance(aStart, aI);
size_t nLen = std::distance(aI, aNext);
aId.mbVerticalMetrics = nGlyphRotation != 0.0;
ApplyFont(cr, aId, nWidth, nHeight, nGlyphRotation, rLayout);
cairo_show_glyphs(cr, &cairo_glyphs[nStartIndex], nLen);
if (cairo_status(cr) != CAIRO_STATUS_SUCCESS)
{
SAL_WARN("vcl", "rendering text failed with stretch ratio of: " << nRatio << ", " << cairo_status_to_string(cairo_status(cr)));
}
#if OSL_DEBUG_LEVEL > 2
//draw origin
cairo_save (cr);
cairo_rectangle (cr, cairo_glyphs[nStartIndex].x, cairo_glyphs[nStartIndex].y, 5, 5);
cairo_set_source_rgba (cr, 1, 0, 0, 0.80);
cairo_fill (cr);
cairo_restore (cr);
#endif
aI = aNext;
}
#if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION)
if (__lsan_enable)
__lsan_enable();
#endif
}
cairo_t* CairoTextRender::getCairoContext()
{
// Note that cairo_set_antialias (bAntiAlias property) doesn't affect cairo
// text rendering. That's affected by cairo_font_options_set_antialias instead.
return mrCairoCommon.getCairoContext(/*bXorModeAllowed*/false, /*bAntiAlias*/true);
}
void CairoTextRender::releaseCairoContext(cairo_t* cr)
{
mrCairoCommon.releaseCairoContext(cr, /*bXorModeAllowed*/false, basegfx::B2DRange());
}
void FontConfigFontOptions::cairo_font_options_substitute(FcPattern* pPattern)
{
const cairo_font_options_t* pFontOptions = GetSalInstance()->GetCairoFontOptions();
if( !pFontOptions )
return;
cairo_ft_font_options_substitute(pFontOptions, pPattern);
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
↑ V530 The return value of function 'append' is required to be utilized.