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qt6-bb10/src/gui/text/qfontengine.cpp

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/****************************************************************************
**
** Copyright (C) 2018 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtGui module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
** Public license version 3 or any later version approved by the KDE Free
** Qt Foundation. The licenses are as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-2.0.html and
** https://www.gnu.org/licenses/gpl-3.0.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include <qdebug.h>
#include <private/qfontengine_p.h>
#include <private/qfontengineglyphcache_p.h>
#include <private/qguiapplication_p.h>
#include <qpa/qplatformfontdatabase.h>
#include <qpa/qplatformintegration.h>
#include "qbitmap.h"
#include "qpainter.h"
#include "qpainterpath.h"
#include "qvarlengtharray.h"
#include <qmath.h>
#include <qendian.h>
#include <private/qstringiterator_p.h>
#if QT_CONFIG(harfbuzz)
# include "qharfbuzzng_p.h"
# include <harfbuzz/hb-ot.h>
#endif
#include <private/qharfbuzz_p.h>
#include <algorithm>
#include <limits.h>
QT_BEGIN_NAMESPACE
static inline bool qtransform_equals_no_translate(const QTransform &a, const QTransform &b)
{
if (a.type() <= QTransform::TxTranslate && b.type() <= QTransform::TxTranslate) {
return true;
} else {
// We always use paths for perspective text anyway, so no
// point in checking the full matrix...
Q_ASSERT(a.type() < QTransform::TxProject);
Q_ASSERT(b.type() < QTransform::TxProject);
return a.m11() == b.m11()
&& a.m12() == b.m12()
&& a.m21() == b.m21()
&& a.m22() == b.m22();
}
}
template<typename T>
static inline bool qSafeFromBigEndian(const uchar *source, const uchar *end, T *output)
{
if (source + sizeof(T) > end)
return false;
*output = qFromBigEndian<T>(source);
return true;
}
// Harfbuzz helper functions
#if QT_CONFIG(harfbuzz)
Q_GLOBAL_STATIC_WITH_ARGS(bool, useHarfbuzzNG,(qgetenv("QT_HARFBUZZ") != "old"))
bool qt_useHarfbuzzNG()
{
return *useHarfbuzzNG();
}
#endif
Q_STATIC_ASSERT(sizeof(HB_Glyph) == sizeof(glyph_t));
Q_STATIC_ASSERT(sizeof(HB_Fixed) == sizeof(QFixed));
static HB_Bool hb_stringToGlyphs(HB_Font font, const HB_UChar16 *string, hb_uint32 length, HB_Glyph *glyphs, hb_uint32 *numGlyphs, HB_Bool rightToLeft)
{
QFontEngine *fe = (QFontEngine *)font->userData;
const QChar *str = reinterpret_cast<const QChar *>(string);
QGlyphLayout qglyphs;
qglyphs.numGlyphs = *numGlyphs;
qglyphs.glyphs = glyphs;
int nGlyphs = *numGlyphs;
bool result = fe->stringToCMap(str, length, &qglyphs, &nGlyphs, QFontEngine::GlyphIndicesOnly);
*numGlyphs = nGlyphs;
if (rightToLeft && result && !fe->symbol) {
QStringIterator it(str, str + length);
while (it.hasNext()) {
const uint ucs4 = it.next();
const uint mirrored = QChar::mirroredChar(ucs4);
if (Q_UNLIKELY(mirrored != ucs4))
*glyphs = fe->glyphIndex(mirrored);
++glyphs;
}
}
return result;
}
static void hb_getAdvances(HB_Font font, const HB_Glyph *glyphs, hb_uint32 numGlyphs, HB_Fixed *advances, int flags)
{
QFontEngine *fe = (QFontEngine *)font->userData;
QGlyphLayout qglyphs;
qglyphs.numGlyphs = numGlyphs;
qglyphs.glyphs = const_cast<glyph_t *>(glyphs);
qglyphs.advances = reinterpret_cast<QFixed *>(advances);
fe->recalcAdvances(&qglyphs, (flags & HB_ShaperFlag_UseDesignMetrics) ? QFontEngine::DesignMetrics : QFontEngine::ShaperFlags(0));
}
static HB_Bool hb_canRender(HB_Font font, const HB_UChar16 *string, hb_uint32 length)
{
QFontEngine *fe = (QFontEngine *)font->userData;
return fe->canRender(reinterpret_cast<const QChar *>(string), length);
}
static void hb_getGlyphMetrics(HB_Font font, HB_Glyph glyph, HB_GlyphMetrics *metrics)
{
QFontEngine *fe = (QFontEngine *)font->userData;
glyph_metrics_t m = fe->boundingBox(glyph);
metrics->x = m.x.value();
metrics->y = m.y.value();
metrics->width = m.width.value();
metrics->height = m.height.value();
metrics->xOffset = m.xoff.value();
metrics->yOffset = m.yoff.value();
}
static HB_Fixed hb_getFontMetric(HB_Font font, HB_FontMetric metric)
{
if (metric == HB_FontAscent) {
QFontEngine *fe = (QFontEngine *)font->userData;
return fe->ascent().value();
}
return 0;
}
int QFontEngine::getPointInOutline(glyph_t glyph, int flags, quint32 point, QFixed *xpos, QFixed *ypos, quint32 *nPoints)
{
Q_UNUSED(glyph)
Q_UNUSED(flags)
Q_UNUSED(point)
Q_UNUSED(xpos)
Q_UNUSED(ypos)
Q_UNUSED(nPoints)
return Err_Not_Covered;
}
static HB_Error hb_getPointInOutline(HB_Font font, HB_Glyph glyph, int flags, hb_uint32 point, HB_Fixed *xpos, HB_Fixed *ypos, hb_uint32 *nPoints)
{
QFontEngine *fe = (QFontEngine *)font->userData;
return (HB_Error)fe->getPointInOutline(glyph, flags, point, (QFixed *)xpos, (QFixed *)ypos, (quint32 *)nPoints);
}
static const HB_FontClass hb_fontClass = {
hb_stringToGlyphs, hb_getAdvances, hb_canRender, hb_getPointInOutline,
hb_getGlyphMetrics, hb_getFontMetric
};
static HB_Error hb_getSFntTable(void *font, HB_Tag tableTag, HB_Byte *buffer, HB_UInt *length)
{
QFontEngine::FaceData *data = (QFontEngine::FaceData *)font;
Q_ASSERT(data);
qt_get_font_table_func_t get_font_table = data->get_font_table;
Q_ASSERT(get_font_table);
if (!get_font_table(data->user_data, tableTag, buffer, length))
return HB_Err_Invalid_Argument;
return HB_Err_Ok;
}
static void hb_freeFace(void *face)
{
qHBFreeFace((HB_Face)face);
}
static bool qt_get_font_table_default(void *user_data, uint tag, uchar *buffer, uint *length)
{
QFontEngine *fe = (QFontEngine *)user_data;
return fe->getSfntTableData(tag, buffer, length);
}
#ifdef QT_BUILD_INTERNAL
// for testing purpose only, not thread-safe!
static QList<QFontEngine *> *enginesCollector = 0;
Q_AUTOTEST_EXPORT void QFontEngine_startCollectingEngines()
{
delete enginesCollector;
enginesCollector = new QList<QFontEngine *>();
}
Q_AUTOTEST_EXPORT QList<QFontEngine *> QFontEngine_stopCollectingEngines()
{
Q_ASSERT(enginesCollector);
QList<QFontEngine *> ret = *enginesCollector;
delete enginesCollector;
enginesCollector = 0;
return ret;
}
#endif // QT_BUILD_INTERNAL
// QFontEngine
#define kBearingNotInitialized std::numeric_limits<qreal>::max()
QFontEngine::QFontEngine(Type type)
: m_type(type), ref(0),
font_(),
face_(),
m_minLeftBearing(kBearingNotInitialized),
m_minRightBearing(kBearingNotInitialized)
{
faceData.user_data = this;
faceData.get_font_table = qt_get_font_table_default;
cache_cost = 0;
fsType = 0;
symbol = false;
isSmoothlyScalable = false;
glyphFormat = Format_None;
m_subPixelPositionCount = 0;
#ifdef QT_BUILD_INTERNAL
if (enginesCollector)
enginesCollector->append(this);
#endif
}
QFontEngine::~QFontEngine()
{
#ifdef QT_BUILD_INTERNAL
if (enginesCollector)
enginesCollector->removeOne(this);
#endif
}
QFixed QFontEngine::lineThickness() const
{
// ad hoc algorithm
int score = fontDef.weight * fontDef.pixelSize;
int lw = score / 700;
// looks better with thicker line for small pointsizes
if (lw < 2 && score >= 1050) lw = 2;
if (lw == 0) lw = 1;
return lw;
}
QFixed QFontEngine::underlinePosition() const
{
return ((lineThickness() * 2) + 3) / 6;
}
void *QFontEngine::harfbuzzFont() const
{
Q_ASSERT(type() != QFontEngine::Multi);
#if QT_CONFIG(harfbuzz)
if (qt_useHarfbuzzNG())
return hb_qt_font_get_for_engine(const_cast<QFontEngine *>(this));
#endif
if (!font_) {
HB_Face hbFace = (HB_Face)harfbuzzFace();
if (hbFace->font_for_init) {
void *data = hbFace->font_for_init;
q_check_ptr(qHBLoadFace(hbFace));
free(data);
}
HB_FontRec *hbFont = (HB_FontRec *) malloc(sizeof(HB_FontRec));
Q_CHECK_PTR(hbFont);
hbFont->klass = &hb_fontClass;
hbFont->userData = const_cast<QFontEngine *>(this);
qint64 emSquare = emSquareSize().truncate();
Q_ASSERT(emSquare == emSquareSize().toInt()); // ensure no truncation
if (emSquare == 0)
emSquare = 1000; // a fallback value suitable for Type1 fonts
hbFont->y_ppem = fontDef.pixelSize;
hbFont->x_ppem = fontDef.pixelSize * fontDef.stretch / 100;
// same as QFixed(x)/QFixed(emSquare) but without int32 overflow for x
hbFont->x_scale = (((qint64)hbFont->x_ppem << 6) * 0x10000L + (emSquare >> 1)) / emSquare;
hbFont->y_scale = (((qint64)hbFont->y_ppem << 6) * 0x10000L + (emSquare >> 1)) / emSquare;
font_ = Holder(hbFont, free);
}
return font_.get();
}
void *QFontEngine::harfbuzzFace() const
{
Q_ASSERT(type() != QFontEngine::Multi);
#if QT_CONFIG(harfbuzz)
if (qt_useHarfbuzzNG())
return hb_qt_face_get_for_engine(const_cast<QFontEngine *>(this));
#endif
if (!face_) {
QFontEngine::FaceData *data = (QFontEngine::FaceData *)malloc(sizeof(QFontEngine::FaceData));
Q_CHECK_PTR(data);
data->user_data = faceData.user_data;
data->get_font_table = faceData.get_font_table;
HB_Face hbFace = qHBNewFace(data, hb_getSFntTable);
Q_CHECK_PTR(hbFace);
hbFace->isSymbolFont = symbol;
face_ = Holder(hbFace, hb_freeFace);
}
return face_.get();
}
bool QFontEngine::supportsScript(QChar::Script script) const
{
if (type() <= QFontEngine::Multi)
return true;
// ### TODO: This only works for scripts that require OpenType. More generally
// for scripts that do not require OpenType we should just look at the list of
// supported writing systems in the font's OS/2 table.
if (!scriptRequiresOpenType(script))
return true;
#if QT_CONFIG(harfbuzz)
if (qt_useHarfbuzzNG()) {
#if defined(Q_OS_DARWIN)
// in AAT fonts, 'gsub' table is effectively replaced by 'mort'/'morx' table
uint len;
if (getSfntTableData(MAKE_TAG('m','o','r','t'), 0, &len) || getSfntTableData(MAKE_TAG('m','o','r','x'), 0, &len))
return true;
#endif
bool ret = false;
if (hb_face_t *face = hb_qt_face_get_for_engine(const_cast<QFontEngine *>(this))) {
hb_tag_t script_tag_1, script_tag_2;
hb_ot_tags_from_script(hb_qt_script_to_script(script), &script_tag_1, &script_tag_2);
unsigned int script_index;
ret = hb_ot_layout_table_find_script(face, HB_OT_TAG_GSUB, script_tag_1, &script_index);
if (!ret) {
ret = hb_ot_layout_table_find_script(face, HB_OT_TAG_GSUB, script_tag_2, &script_index);
if (!ret && script_tag_2 != HB_OT_TAG_DEFAULT_SCRIPT)
ret = hb_ot_layout_table_find_script(face, HB_OT_TAG_GSUB, HB_OT_TAG_DEFAULT_SCRIPT, &script_index);
}
}
return ret;
}
#endif
HB_Face hbFace = (HB_Face)harfbuzzFace();
if (hbFace->font_for_init) {
void *data = hbFace->font_for_init;
q_check_ptr(qHBLoadFace(hbFace));
free(data);
}
return hbFace->supported_scripts[script_to_hbscript(script)];
}
bool QFontEngine::canRender(const QChar *str, int len) const
{
QStringIterator it(str, str + len);
while (it.hasNext()) {
if (glyphIndex(it.next()) == 0)
return false;
}
return true;
}
glyph_metrics_t QFontEngine::boundingBox(glyph_t glyph, const QTransform &matrix)
{
glyph_metrics_t metrics = boundingBox(glyph);
if (matrix.type() > QTransform::TxTranslate) {
return metrics.transformed(matrix);
}
return metrics;
}
QFixed QFontEngine::calculatedCapHeight() const
{
const glyph_t glyph = glyphIndex('H');
glyph_metrics_t bb = const_cast<QFontEngine *>(this)->boundingBox(glyph);
return bb.height;
}
QFixed QFontEngine::xHeight() const
{
const glyph_t glyph = glyphIndex('x');
glyph_metrics_t bb = const_cast<QFontEngine *>(this)->boundingBox(glyph);
return bb.height;
}
QFixed QFontEngine::averageCharWidth() const
{
const glyph_t glyph = glyphIndex('x');
glyph_metrics_t bb = const_cast<QFontEngine *>(this)->boundingBox(glyph);
return bb.xoff;
}
bool QFontEngine::supportsTransformation(const QTransform &transform) const
{
return transform.type() < QTransform::TxProject;
}
bool QFontEngine::expectsGammaCorrectedBlending() const
{
return true;
}
void QFontEngine::getGlyphPositions(const QGlyphLayout &glyphs, const QTransform &matrix, QTextItem::RenderFlags flags,
QVarLengthArray<glyph_t> &glyphs_out, QVarLengthArray<QFixedPoint> &positions)
{
QFixed xpos;
QFixed ypos;
const bool transform = matrix.m11() != 1.
|| matrix.m12() != 0.
|| matrix.m21() != 0.
|| matrix.m22() != 1.;
if (!transform) {
xpos = QFixed::fromReal(matrix.dx());
ypos = QFixed::fromReal(matrix.dy());
}
int current = 0;
if (flags & QTextItem::RightToLeft) {
int i = glyphs.numGlyphs;
int totalKashidas = 0;
while(i--) {
if (glyphs.attributes[i].dontPrint)
continue;
xpos += glyphs.advances[i] + QFixed::fromFixed(glyphs.justifications[i].space_18d6);
totalKashidas += glyphs.justifications[i].nKashidas;
}
positions.resize(glyphs.numGlyphs+totalKashidas);
glyphs_out.resize(glyphs.numGlyphs+totalKashidas);
i = 0;
while(i < glyphs.numGlyphs) {
if (glyphs.attributes[i].dontPrint) {
++i;
continue;
}
xpos -= glyphs.advances[i];
QFixed gpos_x = xpos + glyphs.offsets[i].x;
QFixed gpos_y = ypos + glyphs.offsets[i].y;
if (transform) {
QPointF gpos(gpos_x.toReal(), gpos_y.toReal());
gpos = gpos * matrix;
gpos_x = QFixed::fromReal(gpos.x());
gpos_y = QFixed::fromReal(gpos.y());
}
positions[current].x = gpos_x;
positions[current].y = gpos_y;
glyphs_out[current] = glyphs.glyphs[i];
++current;
if (glyphs.justifications[i].nKashidas) {
QChar ch(0x640); // Kashida character
glyph_t kashidaGlyph = glyphIndex(ch.unicode());
QFixed kashidaWidth;
QGlyphLayout g;
g.numGlyphs = 1;
g.glyphs = &kashidaGlyph;
g.advances = &kashidaWidth;
recalcAdvances(&g, 0);
for (uint k = 0; k < glyphs.justifications[i].nKashidas; ++k) {
xpos -= kashidaWidth;
QFixed gpos_x = xpos + glyphs.offsets[i].x;
QFixed gpos_y = ypos + glyphs.offsets[i].y;
if (transform) {
QPointF gpos(gpos_x.toReal(), gpos_y.toReal());
gpos = gpos * matrix;
gpos_x = QFixed::fromReal(gpos.x());
gpos_y = QFixed::fromReal(gpos.y());
}
positions[current].x = gpos_x;
positions[current].y = gpos_y;
glyphs_out[current] = kashidaGlyph;
++current;
}
} else {
xpos -= QFixed::fromFixed(glyphs.justifications[i].space_18d6);
}
++i;
}
} else {
positions.resize(glyphs.numGlyphs);
glyphs_out.resize(glyphs.numGlyphs);
int i = 0;
if (!transform) {
while (i < glyphs.numGlyphs) {
if (!glyphs.attributes[i].dontPrint) {
positions[current].x = xpos + glyphs.offsets[i].x;
positions[current].y = ypos + glyphs.offsets[i].y;
glyphs_out[current] = glyphs.glyphs[i];
xpos += glyphs.advances[i] + QFixed::fromFixed(glyphs.justifications[i].space_18d6);
++current;
}
++i;
}
} else {
while (i < glyphs.numGlyphs) {
if (!glyphs.attributes[i].dontPrint) {
QFixed gpos_x = xpos + glyphs.offsets[i].x;
QFixed gpos_y = ypos + glyphs.offsets[i].y;
QPointF gpos(gpos_x.toReal(), gpos_y.toReal());
gpos = gpos * matrix;
positions[current].x = QFixed::fromReal(gpos.x());
positions[current].y = QFixed::fromReal(gpos.y());
glyphs_out[current] = glyphs.glyphs[i];
xpos += glyphs.advances[i] + QFixed::fromFixed(glyphs.justifications[i].space_18d6);
++current;
}
++i;
}
}
}
positions.resize(current);
glyphs_out.resize(current);
Q_ASSERT(positions.size() == glyphs_out.size());
}
void QFontEngine::getGlyphBearings(glyph_t glyph, qreal *leftBearing, qreal *rightBearing)
{
glyph_metrics_t gi = boundingBox(glyph);
if (leftBearing != 0)
*leftBearing = gi.leftBearing().toReal();
if (rightBearing != 0)
*rightBearing = gi.rightBearing().toReal();
}
qreal QFontEngine::minLeftBearing() const
{
if (m_minLeftBearing == kBearingNotInitialized)
minRightBearing(); // Initializes both (see below)
return m_minLeftBearing;
}
#define q16Dot16ToFloat(i) ((i) / 65536.0)
#define kMinLeftSideBearingOffset 12
#define kMinRightSideBearingOffset 14
qreal QFontEngine::minRightBearing() const
{
if (m_minRightBearing == kBearingNotInitialized) {
// Try the 'hhea' font table first, which covers the entire font
QByteArray hheaTable = getSfntTable(MAKE_TAG('h', 'h', 'e', 'a'));
if (hheaTable.size() >= int(kMinRightSideBearingOffset + sizeof(qint16))) {
const uchar *tableData = reinterpret_cast<const uchar *>(hheaTable.constData());
Q_ASSERT(q16Dot16ToFloat(qFromBigEndian<quint32>(tableData)) == 1.0);
qint16 minLeftSideBearing = qFromBigEndian<qint16>(tableData + kMinLeftSideBearingOffset);
qint16 minRightSideBearing = qFromBigEndian<qint16>(tableData + kMinRightSideBearingOffset);
// The table data is expressed as FUnits, meaning we have to take the number
// of units per em into account. Since pixelSize already has taken DPI into
// account we can use that directly instead of the point size.
int unitsPerEm = emSquareSize().toInt();
qreal funitToPixelFactor = fontDef.pixelSize / unitsPerEm;
// Some fonts on OS X (such as Gurmukhi Sangam MN, Khmer MN, Lao Sangam MN, etc.), have
// invalid values for their NBSPACE left bearing, causing the 'hhea' minimum bearings to
// be way off. We detect this by assuming that the minimum bearsings are within a certain
// range of the em square size.
static const int largestValidBearing = 4 * unitsPerEm;
if (qAbs(minLeftSideBearing) < largestValidBearing)
m_minLeftBearing = minLeftSideBearing * funitToPixelFactor;
if (qAbs(minRightSideBearing) < largestValidBearing)
m_minRightBearing = minRightSideBearing * funitToPixelFactor;
}
// Fallback in case of missing 'hhea' table (bitmap fonts e.g.) or broken 'hhea' values
if (m_minLeftBearing == kBearingNotInitialized || m_minRightBearing == kBearingNotInitialized) {
// To balance performance and correctness we only look at a subset of the
// possible glyphs in the font, based on which characters are more likely
// to have a left or right bearing.
static const ushort characterSubset[] = {
'(', 'C', 'F', 'K', 'V', 'X', 'Y', ']', '_', 'f', 'r', '|',
127, 205, 645, 884, 922, 1070, 12386
};
// The font may have minimum bearings larger than 0, so we have to start at the max
m_minLeftBearing = m_minRightBearing = std::numeric_limits<qreal>::max();
for (uint i = 0; i < (sizeof(characterSubset) / sizeof(ushort)); ++i) {
const glyph_t glyph = glyphIndex(characterSubset[i]);
if (!glyph)
continue;
glyph_metrics_t glyphMetrics = const_cast<QFontEngine *>(this)->boundingBox(glyph);
// Glyphs with no contours shouldn't contribute to bearings
if (!glyphMetrics.width || !glyphMetrics.height)
continue;
m_minLeftBearing = qMin(m_minLeftBearing, glyphMetrics.leftBearing().toReal());
m_minRightBearing = qMin(m_minRightBearing, glyphMetrics.rightBearing().toReal());
}
}
if (m_minLeftBearing == kBearingNotInitialized || m_minRightBearing == kBearingNotInitialized)
qWarning() << "Failed to compute left/right minimum bearings for" << fontDef.family;
}
return m_minRightBearing;
}
glyph_metrics_t QFontEngine::tightBoundingBox(const QGlyphLayout &glyphs)
{
glyph_metrics_t overall;
QFixed ymax = 0;
QFixed xmax = 0;
for (int i = 0; i < glyphs.numGlyphs; i++) {
glyph_metrics_t bb = boundingBox(glyphs.glyphs[i]);
QFixed x = overall.xoff + glyphs.offsets[i].x + bb.x;
QFixed y = overall.yoff + glyphs.offsets[i].y + bb.y;
overall.x = qMin(overall.x, x);
overall.y = qMin(overall.y, y);
xmax = qMax(xmax, x + bb.width);
ymax = qMax(ymax, y + bb.height);
overall.xoff += bb.xoff;
overall.yoff += bb.yoff;
}
overall.height = qMax(overall.height, ymax - overall.y);
overall.width = xmax - overall.x;
return overall;
}
void QFontEngine::addOutlineToPath(qreal x, qreal y, const QGlyphLayout &glyphs, QPainterPath *path,
QTextItem::RenderFlags flags)
{
if (!glyphs.numGlyphs)
return;
QVarLengthArray<QFixedPoint> positions;
QVarLengthArray<glyph_t> positioned_glyphs;
QTransform matrix = QTransform::fromTranslate(x, y);
getGlyphPositions(glyphs, matrix, flags, positioned_glyphs, positions);
addGlyphsToPath(positioned_glyphs.data(), positions.data(), positioned_glyphs.size(), path, flags);
}
#define GRID(x, y) grid[(y)*(w+1) + (x)]
#define SET(x, y) (*(image_data + (y)*bpl + ((x) >> 3)) & (0x80 >> ((x) & 7)))
enum { EdgeRight = 0x1,
EdgeDown = 0x2,
EdgeLeft = 0x4,
EdgeUp = 0x8
};
static void collectSingleContour(qreal x0, qreal y0, uint *grid, int x, int y, int w, int h, QPainterPath *path)
{
Q_UNUSED(h);
path->moveTo(x + x0, y + y0);
while (GRID(x, y)) {
if (GRID(x, y) & EdgeRight) {
while (GRID(x, y) & EdgeRight) {
GRID(x, y) &= ~EdgeRight;
++x;
}
Q_ASSERT(x <= w);
path->lineTo(x + x0, y + y0);
continue;
}
if (GRID(x, y) & EdgeDown) {
while (GRID(x, y) & EdgeDown) {
GRID(x, y) &= ~EdgeDown;
++y;
}
Q_ASSERT(y <= h);
path->lineTo(x + x0, y + y0);
continue;
}
if (GRID(x, y) & EdgeLeft) {
while (GRID(x, y) & EdgeLeft) {
GRID(x, y) &= ~EdgeLeft;
--x;
}
Q_ASSERT(x >= 0);
path->lineTo(x + x0, y + y0);
continue;
}
if (GRID(x, y) & EdgeUp) {
while (GRID(x, y) & EdgeUp) {
GRID(x, y) &= ~EdgeUp;
--y;
}
Q_ASSERT(y >= 0);
path->lineTo(x + x0, y + y0);
continue;
}
}
path->closeSubpath();
}
Q_GUI_EXPORT void qt_addBitmapToPath(qreal x0, qreal y0, const uchar *image_data, int bpl, int w, int h, QPainterPath *path)
{
uint *grid = new uint[(w+1)*(h+1)];
// set up edges
for (int y = 0; y <= h; ++y) {
for (int x = 0; x <= w; ++x) {
bool topLeft = (x == 0)|(y == 0) ? false : SET(x - 1, y - 1);
bool topRight = (x == w)|(y == 0) ? false : SET(x, y - 1);
bool bottomLeft = (x == 0)|(y == h) ? false : SET(x - 1, y);
bool bottomRight = (x == w)|(y == h) ? false : SET(x, y);
GRID(x, y) = 0;
if ((!topRight) & bottomRight)
GRID(x, y) |= EdgeRight;
if ((!bottomRight) & bottomLeft)
GRID(x, y) |= EdgeDown;
if ((!bottomLeft) & topLeft)
GRID(x, y) |= EdgeLeft;
if ((!topLeft) & topRight)
GRID(x, y) |= EdgeUp;
}
}
// collect edges
for (int y = 0; y < h; ++y) {
for (int x = 0; x < w; ++x) {
if (!GRID(x, y))
continue;
// found start of a contour, follow it
collectSingleContour(x0, y0, grid, x, y, w, h, path);
}
}
delete [] grid;
}
#undef GRID
#undef SET
void QFontEngine::addBitmapFontToPath(qreal x, qreal y, const QGlyphLayout &glyphs,
QPainterPath *path, QTextItem::RenderFlags flags)
{
// TODO what to do with 'flags' ??
Q_UNUSED(flags);
QFixed advanceX = QFixed::fromReal(x);
QFixed advanceY = QFixed::fromReal(y);
for (int i=0; i < glyphs.numGlyphs; ++i) {
glyph_metrics_t metrics = boundingBox(glyphs.glyphs[i]);
if (metrics.width.value() == 0 || metrics.height.value() == 0) {
advanceX += glyphs.advances[i];
continue;
}
const QImage alphaMask = alphaMapForGlyph(glyphs.glyphs[i]);
const int w = alphaMask.width();
const int h = alphaMask.height();
const int srcBpl = alphaMask.bytesPerLine();
QImage bitmap;
if (alphaMask.depth() == 1) {
bitmap = alphaMask;
} else {
bitmap = QImage(w, h, QImage::Format_Mono);
const uchar *imageData = alphaMask.bits();
const int destBpl = bitmap.bytesPerLine();
uchar *bitmapData = bitmap.bits();
for (int yi = 0; yi < h; ++yi) {
const uchar *src = imageData + yi*srcBpl;
uchar *dst = bitmapData + yi*destBpl;
for (int xi = 0; xi < w; ++xi) {
const int byte = xi / 8;
const int bit = xi % 8;
if (bit == 0)
dst[byte] = 0;
if (src[xi])
dst[byte] |= 128 >> bit;
}
}
}
const uchar *bitmap_data = bitmap.constBits();
QFixedPoint offset = glyphs.offsets[i];
advanceX += offset.x;
advanceY += offset.y;
qt_addBitmapToPath((advanceX + metrics.x).toReal(), (advanceY + metrics.y).toReal(), bitmap_data, bitmap.bytesPerLine(), w, h, path);
advanceX += glyphs.advances[i];
}
}
void QFontEngine::addGlyphsToPath(glyph_t *glyphs, QFixedPoint *positions, int nGlyphs,
QPainterPath *path, QTextItem::RenderFlags flags)
{
qreal x = positions[0].x.toReal();
qreal y = positions[0].y.toReal();
QVarLengthGlyphLayoutArray g(nGlyphs);
for (int i = 0; i < nGlyphs - 1; ++i) {
g.glyphs[i] = glyphs[i];
g.advances[i] = positions[i + 1].x - positions[i].x;
}
g.glyphs[nGlyphs - 1] = glyphs[nGlyphs - 1];
g.advances[nGlyphs - 1] = QFixed::fromReal(maxCharWidth());
addBitmapFontToPath(x, y, g, path, flags);
}
QImage QFontEngine::alphaMapForGlyph(glyph_t glyph, QFixed /*subPixelPosition*/)
{
// For font engines don't support subpixel positioning
return alphaMapForGlyph(glyph);
}
QImage QFontEngine::alphaMapForGlyph(glyph_t glyph, const QTransform &t)
{
QImage i = alphaMapForGlyph(glyph);
if (t.type() > QTransform::TxTranslate)
i = i.transformed(t).convertToFormat(QImage::Format_Alpha8);
Q_ASSERT(i.depth() <= 8); // To verify that transformed didn't change the format...
return i;
}
QImage QFontEngine::alphaMapForGlyph(glyph_t glyph, QFixed subPixelPosition, const QTransform &t)
{
if (! supportsSubPixelPositions())
return alphaMapForGlyph(glyph, t);
QImage i = alphaMapForGlyph(glyph, subPixelPosition);
if (t.type() > QTransform::TxTranslate)
i = i.transformed(t).convertToFormat(QImage::Format_Alpha8);
Q_ASSERT(i.depth() <= 8); // To verify that transformed didn't change the format...
return i;
}
QImage QFontEngine::alphaRGBMapForGlyph(glyph_t glyph, QFixed /*subPixelPosition*/, const QTransform &t)
{
const QImage alphaMask = alphaMapForGlyph(glyph, t);
QImage rgbMask(alphaMask.width(), alphaMask.height(), QImage::Format_RGB32);
for (int y=0; y<alphaMask.height(); ++y) {
uint *dst = (uint *) rgbMask.scanLine(y);
const uchar *src = alphaMask.constScanLine(y);
for (int x=0; x<alphaMask.width(); ++x) {
int val = src[x];
dst[x] = qRgb(val, val, val);
}
}
return rgbMask;
}
QImage QFontEngine::bitmapForGlyph(glyph_t, QFixed subPixelPosition, const QTransform&)
{
Q_UNUSED(subPixelPosition);
return QImage();
}
QFixed QFontEngine::subPixelPositionForX(QFixed x) const
{
if (m_subPixelPositionCount <= 1 || !supportsSubPixelPositions())
return QFixed();
QFixed subPixelPosition;
if (x != 0) {
subPixelPosition = x - x.floor();
QFixed fraction = (subPixelPosition / QFixed::fromReal(1.0 / m_subPixelPositionCount)).floor();
// Compensate for precision loss in fixed point to make sure we are always drawing at a subpixel position over
// the lower boundary for the selected rasterization by adding 1/64.
subPixelPosition = fraction / QFixed(m_subPixelPositionCount) + QFixed::fromReal(0.015625);
}
return subPixelPosition;
}
QImage *QFontEngine::lockedAlphaMapForGlyph(glyph_t glyph, QFixed subPixelPosition,
QFontEngine::GlyphFormat neededFormat,
const QTransform &t, QPoint *offset)
{
Q_ASSERT(currentlyLockedAlphaMap.isNull());
if (neededFormat == Format_None)
neededFormat = Format_A32;
if (neededFormat != Format_A32)
currentlyLockedAlphaMap = alphaMapForGlyph(glyph, subPixelPosition, t);
else
currentlyLockedAlphaMap = alphaRGBMapForGlyph(glyph, subPixelPosition, t);
if (offset != 0)
*offset = QPoint(0, 0);
return &currentlyLockedAlphaMap;
}
void QFontEngine::unlockAlphaMapForGlyph()
{
Q_ASSERT(!currentlyLockedAlphaMap.isNull());
currentlyLockedAlphaMap = QImage();
}
QImage QFontEngine::alphaMapForGlyph(glyph_t glyph)
{
glyph_metrics_t gm = boundingBox(glyph);
int glyph_x = qFloor(gm.x.toReal());
int glyph_y = qFloor(gm.y.toReal());
int glyph_width = qCeil((gm.x + gm.width).toReal()) - glyph_x;
int glyph_height = qCeil((gm.y + gm.height).toReal()) - glyph_y;
if (glyph_width <= 0 || glyph_height <= 0)
return QImage();
QFixedPoint pt;
pt.x = -glyph_x;
pt.y = -glyph_y; // the baseline
QPainterPath path;
path.setFillRule(Qt::WindingFill);
QImage im(glyph_width, glyph_height, QImage::Format_ARGB32_Premultiplied);
im.fill(Qt::transparent);
QPainter p(&im);
p.setRenderHint(QPainter::Antialiasing);
addGlyphsToPath(&glyph, &pt, 1, &path, 0);
p.setPen(Qt::NoPen);
p.setBrush(Qt::black);
p.drawPath(path);
p.end();
QImage alphaMap(im.width(), im.height(), QImage::Format_Alpha8);
for (int y=0; y<im.height(); ++y) {
uchar *dst = (uchar *) alphaMap.scanLine(y);
const uint *src = reinterpret_cast<const uint *>(im.constScanLine(y));
for (int x=0; x<im.width(); ++x)
dst[x] = qAlpha(src[x]);
}
return alphaMap;
}
void QFontEngine::removeGlyphFromCache(glyph_t)
{
}
QFontEngine::Properties QFontEngine::properties() const
{
Properties p;
p.postscriptName
= QFontEngine::convertToPostscriptFontFamilyName(fontDef.family.toUtf8())
+ '-'
+ QByteArray::number(fontDef.style)
+ '-'
+ QByteArray::number(fontDef.weight);
p.ascent = ascent();
p.descent = descent();
p.leading = leading();
p.emSquare = p.ascent;
p.boundingBox = QRectF(0, -p.ascent.toReal(), maxCharWidth(), (p.ascent + p.descent).toReal());
p.italicAngle = 0;
p.capHeight = p.ascent;
p.lineWidth = lineThickness();
return p;
}
void QFontEngine::getUnscaledGlyph(glyph_t glyph, QPainterPath *path, glyph_metrics_t *metrics)
{
*metrics = boundingBox(glyph);
QFixedPoint p;
p.x = 0;
p.y = 0;
addGlyphsToPath(&glyph, &p, 1, path, QFlag(0));
}
/*!
Returns \c true if the font table idetified by \a tag exists in the font;
returns \c false otherwise.
If \a buffer is NULL, stores the size of the buffer required for the font table data,
in bytes, in \a length. If \a buffer is not NULL and the capacity
of the buffer, passed in \a length, is sufficient to store the font table data,
also copies the font table data to \a buffer.
Note: returning \c false when the font table exists could lead to an undefined behavior.
*/
bool QFontEngine::getSfntTableData(uint tag, uchar *buffer, uint *length) const
{
Q_UNUSED(tag)
Q_UNUSED(buffer)
Q_UNUSED(length)
return false;
}
QByteArray QFontEngine::getSfntTable(uint tag) const
{
QByteArray table;
uint len = 0;
if (!getSfntTableData(tag, 0, &len))
return table;
table.resize(len);
if (!getSfntTableData(tag, reinterpret_cast<uchar *>(table.data()), &len))
return QByteArray();
return table;
}
void QFontEngine::clearGlyphCache(const void *context)
{
m_glyphCaches.remove(context);
}
void QFontEngine::setGlyphCache(const void *context, QFontEngineGlyphCache *cache)
{
Q_ASSERT(cache);
GlyphCaches &caches = m_glyphCaches[context];
for (GlyphCaches::const_iterator it = caches.constBegin(), end = caches.constEnd(); it != end; ++it) {
if (cache == it->cache.data())
return;
}
// Limit the glyph caches to 4 per context. This covers all 90 degree rotations,
// and limits memory use when there is continuous or random rotation
if (caches.size() == 4)
caches.removeLast();
GlyphCacheEntry entry;
entry.cache = cache;
caches.push_front(entry);
}
QFontEngineGlyphCache *QFontEngine::glyphCache(const void *context, GlyphFormat format, const QTransform &transform) const
{
const QHash<const void*, GlyphCaches>::const_iterator caches = m_glyphCaches.constFind(context);
if (caches == m_glyphCaches.cend())
return nullptr;
for (GlyphCaches::const_iterator it = caches->begin(), end = caches->end(); it != end; ++it) {
QFontEngineGlyphCache *cache = it->cache.data();
if (format == cache->glyphFormat() && qtransform_equals_no_translate(cache->m_transform, transform))
return cache;
}
return nullptr;
}
static inline QFixed kerning(int left, int right, const QFontEngine::KernPair *pairs, int numPairs)
{
uint left_right = (left << 16) + right;
left = 0, right = numPairs - 1;
while (left <= right) {
int middle = left + ( ( right - left ) >> 1 );
if(pairs[middle].left_right == left_right)
return pairs[middle].adjust;
if (pairs[middle].left_right < left_right)
left = middle + 1;
else
right = middle - 1;
}
return 0;
}
void QFontEngine::doKerning(QGlyphLayout *glyphs, QFontEngine::ShaperFlags flags) const
{
int numPairs = kerning_pairs.size();
if(!numPairs)
return;
const KernPair *pairs = kerning_pairs.constData();
if (flags & DesignMetrics) {
for(int i = 0; i < glyphs->numGlyphs - 1; ++i)
glyphs->advances[i] += kerning(glyphs->glyphs[i], glyphs->glyphs[i+1] , pairs, numPairs);
} else {
for(int i = 0; i < glyphs->numGlyphs - 1; ++i)
glyphs->advances[i] += qRound(kerning(glyphs->glyphs[i], glyphs->glyphs[i+1] , pairs, numPairs));
}
}
void QFontEngine::loadKerningPairs(QFixed scalingFactor)
{
kerning_pairs.clear();
QByteArray tab = getSfntTable(MAKE_TAG('k', 'e', 'r', 'n'));
if (tab.isEmpty())
return;
const uchar *table = reinterpret_cast<const uchar *>(tab.constData());
const uchar *end = table + tab.size();
quint16 version;
if (!qSafeFromBigEndian(table, end, &version))
return;
if (version != 0) {
// qDebug("wrong version");
return;
}
quint16 numTables;
if (!qSafeFromBigEndian(table + 2, end, &numTables))
return;
{
int offset = 4;
for(int i = 0; i < numTables; ++i) {
const uchar *header = table + offset;
quint16 version;
if (!qSafeFromBigEndian(header, end, &version))
goto end;
quint16 length;
if (!qSafeFromBigEndian(header + 2, end, &length))
goto end;
quint16 coverage;
if (!qSafeFromBigEndian(header + 4, end, &coverage))
goto end;
// qDebug("subtable: version=%d, coverage=%x",version, coverage);
if(version == 0 && coverage == 0x0001) {
if (offset + length > tab.size()) {
// qDebug("length ouf ot bounds");
goto end;
}
const uchar *data = table + offset + 6;
quint16 nPairs;
if (!qSafeFromBigEndian(data, end, &nPairs))
goto end;
if(nPairs * 6 + 8 > length - 6) {
// qDebug("corrupt table!");
// corrupt table
goto end;
}
int off = 8;
for(int i = 0; i < nPairs; ++i) {
QFontEngine::KernPair p;
quint16 tmp;
if (!qSafeFromBigEndian(data + off, end, &tmp))
goto end;
p.left_right = uint(tmp) << 16;
if (!qSafeFromBigEndian(data + off + 2, end, &tmp))
goto end;
p.left_right |= tmp;
if (!qSafeFromBigEndian(data + off + 4, end, &tmp))
goto end;
p.adjust = QFixed(int(short(tmp))) / scalingFactor;
kerning_pairs.append(p);
off += 6;
}
}
offset += length;
}
}
end:
std::sort(kerning_pairs.begin(), kerning_pairs.end());
// for (int i = 0; i < kerning_pairs.count(); ++i)
// qDebug() << 'i' << i << "left_right" << hex << kerning_pairs.at(i).left_right;
}
int QFontEngine::glyphCount() const
{
QByteArray maxpTable = getSfntTable(MAKE_TAG('m', 'a', 'x', 'p'));
if (maxpTable.size() < 6)
return 0;
const uchar *source = reinterpret_cast<const uchar *>(maxpTable.constData() + 4);
const uchar *end = source + maxpTable.size();
quint16 count = 0;
qSafeFromBigEndian(source, end, &count);
return count;
}
Qt::HANDLE QFontEngine::handle() const
{
return nullptr;
}
const uchar *QFontEngine::getCMap(const uchar *table, uint tableSize, bool *isSymbolFont, int *cmapSize)
{
const uchar *header = table;
const uchar *endPtr = table + tableSize;
// version check
quint16 version;
if (!qSafeFromBigEndian(header, endPtr, &version) || version != 0)
return 0;
quint16 numTables;
if (!qSafeFromBigEndian(header + 2, endPtr, &numTables))
return 0;
const uchar *maps = table + 4;
enum {
Invalid,
AppleRoman,
Symbol,
Unicode11,
Unicode,
MicrosoftUnicode,
MicrosoftUnicodeExtended
};
int symbolTable = -1;
int tableToUse = -1;
int score = Invalid;
for (int n = 0; n < numTables; ++n) {
quint16 platformId;
if (!qSafeFromBigEndian(maps + 8 * n, endPtr, &platformId))
return 0;
quint16 platformSpecificId = 0;
if (!qSafeFromBigEndian(maps + 8 * n + 2, endPtr, &platformSpecificId))
return 0;
switch (platformId) {
case 0: // Unicode
if (score < Unicode &&
(platformSpecificId == 0 ||
platformSpecificId == 2 ||
platformSpecificId == 3)) {
tableToUse = n;
score = Unicode;
} else if (score < Unicode11 && platformSpecificId == 1) {
tableToUse = n;
score = Unicode11;
}
break;
case 1: // Apple
if (score < AppleRoman && platformSpecificId == 0) { // Apple Roman
tableToUse = n;
score = AppleRoman;
}
break;
case 3: // Microsoft
switch (platformSpecificId) {
case 0:
symbolTable = n;
if (score < Symbol) {
tableToUse = n;
score = Symbol;
}
break;
case 1:
if (score < MicrosoftUnicode) {
tableToUse = n;
score = MicrosoftUnicode;
}
break;
case 0xa:
if (score < MicrosoftUnicodeExtended) {
tableToUse = n;
score = MicrosoftUnicodeExtended;
}
break;
default:
break;
}
default:
break;
}
}
if(tableToUse < 0)
return 0;
resolveTable:
*isSymbolFont = (symbolTable > -1);
quint32 unicode_table = 0;
if (!qSafeFromBigEndian(maps + 8 * tableToUse + 4, endPtr, &unicode_table))
return 0;
if (!unicode_table)
return 0;
// get the header of the unicode table
header = table + unicode_table;
quint16 format;
if (!qSafeFromBigEndian(header, endPtr, &format))
return 0;
quint32 length;
if (format < 8) {
quint16 tmp;
if (!qSafeFromBigEndian(header + 2, endPtr, &tmp))
return 0;
length = tmp;
} else {
if (!qSafeFromBigEndian(header + 4, endPtr, &length))
return 0;
}
if (table + unicode_table + length > endPtr)
return 0;
*cmapSize = length;
// To support symbol fonts that contain a unicode table for the symbol area
// we check the cmap tables and fall back to symbol font unless that would
// involve losing information from the unicode table
if (symbolTable > -1 && ((score == Unicode) || (score == Unicode11))) {
const uchar *selectedTable = table + unicode_table;
// Check that none of the latin1 range are in the unicode table
bool unicodeTableHasLatin1 = false;
for (int uc=0x00; uc<0x100; ++uc) {
if (getTrueTypeGlyphIndex(selectedTable, length, uc) != 0) {
unicodeTableHasLatin1 = true;
break;
}
}
// Check that at least one symbol char is in the unicode table
bool unicodeTableHasSymbols = false;
if (!unicodeTableHasLatin1) {
for (int uc=0xf000; uc<0xf100; ++uc) {
if (getTrueTypeGlyphIndex(selectedTable, length, uc) != 0) {
unicodeTableHasSymbols = true;
break;
}
}
}
// Fall back to symbol table
if (!unicodeTableHasLatin1 && unicodeTableHasSymbols) {
tableToUse = symbolTable;
score = Symbol;
goto resolveTable;
}
}
return table + unicode_table;
}
quint32 QFontEngine::getTrueTypeGlyphIndex(const uchar *cmap, int cmapSize, uint unicode)
{
const uchar *end = cmap + cmapSize;
quint16 format;
if (!qSafeFromBigEndian(cmap, end, &format))
return 0;
if (format == 0) {
const uchar *ptr = cmap + 6 + unicode;
if (unicode < 256 && ptr < end)
return quint32(*ptr);
} else if (format == 4) {
/* some fonts come with invalid cmap tables, where the last segment
specified end = start = rangeoffset = 0xffff, delta = 0x0001
Since 0xffff is never a valid Unicode char anyway, we just get rid of the issue
by returning 0 for 0xffff
*/
if(unicode >= 0xffff)
return 0;
quint16 segCountX2;
if (!qSafeFromBigEndian(cmap + 6, end, &segCountX2))
return 0;
const unsigned char *ends = cmap + 14;
int i = 0;
for (; i < segCountX2/2; ++i) {
quint16 codePoint;
if (!qSafeFromBigEndian(ends + 2 * i, end, &codePoint))
return 0;
if (codePoint >= unicode)
break;
}
const unsigned char *idx = ends + segCountX2 + 2 + 2*i;
quint16 startIndex;
if (!qSafeFromBigEndian(idx, end, &startIndex))
return 0;
if (startIndex > unicode)
return 0;
idx += segCountX2;
quint16 tmp;
if (!qSafeFromBigEndian(idx, end, &tmp))
return 0;
qint16 idDelta = qint16(tmp);
idx += segCountX2;
quint16 idRangeoffset_t;
if (!qSafeFromBigEndian(idx, end, &idRangeoffset_t))
return 0;
quint16 glyphIndex;
if (idRangeoffset_t) {
quint16 id;
if (!qSafeFromBigEndian(idRangeoffset_t + 2 * (unicode - startIndex) + idx, end, &id))
return 0;
if (id)
glyphIndex = (idDelta + id) % 0x10000;
else
glyphIndex = 0;
} else {
glyphIndex = (idDelta + unicode) % 0x10000;
}
return glyphIndex;
} else if (format == 6) {
quint16 tableSize;
if (!qSafeFromBigEndian(cmap + 2, end, &tableSize))
return 0;
quint16 firstCode6;
if (!qSafeFromBigEndian(cmap + 6, end, &firstCode6))
return 0;
if (unicode < firstCode6)
return 0;
quint16 entryCount6;
if (!qSafeFromBigEndian(cmap + 8, end, &entryCount6))
return 0;
if (entryCount6 * 2 + 10 > tableSize)
return 0;
quint16 sentinel6 = firstCode6 + entryCount6;
if (unicode >= sentinel6)
return 0;
quint16 entryIndex6 = unicode - firstCode6;
quint16 index = 0;
qSafeFromBigEndian(cmap + 10 + (entryIndex6 * 2), end, &index);
return index;
} else if (format == 12) {
quint32 nGroups;
if (!qSafeFromBigEndian(cmap + 12, end, &nGroups))
return 0;
cmap += 16; // move to start of groups
int left = 0, right = nGroups - 1;
while (left <= right) {
int middle = left + ( ( right - left ) >> 1 );
quint32 startCharCode;
if (!qSafeFromBigEndian(cmap + 12 * middle, end, &startCharCode))
return 0;
if(unicode < startCharCode)
right = middle - 1;
else {
quint32 endCharCode;
if (!qSafeFromBigEndian(cmap + 12 * middle + 4, end, &endCharCode))
return 0;
if (unicode <= endCharCode) {
quint32 index;
if (!qSafeFromBigEndian(cmap + 12 * middle + 8, end, &index))
return 0;
return index + unicode - startCharCode;
}
left = middle + 1;
}
}
} else {
qDebug("cmap table of format %d not implemented", format);
}
return 0;
}
QByteArray QFontEngine::convertToPostscriptFontFamilyName(const QByteArray &family)
{
QByteArray f = family;
f.replace(' ', "");
f.replace('(', "");
f.replace(')', "");
f.replace('<', "");
f.replace('>', "");
f.replace('[', "");
f.replace(']', "");
f.replace('{', "");
f.replace('}', "");
f.replace('/', "");
f.replace('%', "");
return f;
}
// Allow font engines (e.g. Windows) that can not reliably create
// outline paths for distance-field rendering to switch the scene
// graph over to native text rendering.
bool QFontEngine::hasUnreliableGlyphOutline() const
{
// Color glyphs (Emoji) are generally not suited for outlining
return glyphFormat == QFontEngine::Format_ARGB;
}
QFixed QFontEngine::lastRightBearing(const QGlyphLayout &glyphs, bool round)
{
if (glyphs.numGlyphs >= 1) {
glyph_t glyph = glyphs.glyphs[glyphs.numGlyphs - 1];
glyph_metrics_t gi = boundingBox(glyph);
if (gi.isValid())
return round ? qRound(gi.rightBearing()) : gi.rightBearing();
}
return 0;
}
QFontEngine::GlyphCacheEntry::GlyphCacheEntry()
{
}
QFontEngine::GlyphCacheEntry::GlyphCacheEntry(const GlyphCacheEntry &o)
: cache(o.cache)
{
}
QFontEngine::GlyphCacheEntry::~GlyphCacheEntry()
{
}
QFontEngine::GlyphCacheEntry &QFontEngine::GlyphCacheEntry::operator=(const GlyphCacheEntry &o)
{
cache = o.cache;
return *this;
}
// ------------------------------------------------------------------
// The box font engine
// ------------------------------------------------------------------
QFontEngineBox::QFontEngineBox(int size)
: QFontEngine(Box),
_size(size)
{
cache_cost = sizeof(QFontEngineBox);
}
QFontEngineBox::QFontEngineBox(Type type, int size)
: QFontEngine(type),
_size(size)
{
cache_cost = sizeof(QFontEngineBox);
}
QFontEngineBox::~QFontEngineBox()
{
}
glyph_t QFontEngineBox::glyphIndex(uint ucs4) const
{
Q_UNUSED(ucs4)
return 0;
}
bool QFontEngineBox::stringToCMap(const QChar *str, int len, QGlyphLayout *glyphs, int *nglyphs, QFontEngine::ShaperFlags flags) const
{
Q_ASSERT(glyphs->numGlyphs >= *nglyphs);
if (*nglyphs < len) {
*nglyphs = len;
return false;
}
int ucs4Length = 0;
QStringIterator it(str, str + len);
while (it.hasNext()) {
it.advance();
glyphs->glyphs[ucs4Length++] = 0;
}
*nglyphs = ucs4Length;
glyphs->numGlyphs = ucs4Length;
if (!(flags & GlyphIndicesOnly))
recalcAdvances(glyphs, flags);
return true;
}
void QFontEngineBox::recalcAdvances(QGlyphLayout *glyphs, QFontEngine::ShaperFlags) const
{
for (int i = 0; i < glyphs->numGlyphs; i++)
glyphs->advances[i] = _size;
}
void QFontEngineBox::addOutlineToPath(qreal x, qreal y, const QGlyphLayout &glyphs, QPainterPath *path, QTextItem::RenderFlags flags)
{
if (!glyphs.numGlyphs)
return;
QVarLengthArray<QFixedPoint> positions;
QVarLengthArray<glyph_t> positioned_glyphs;
QTransform matrix = QTransform::fromTranslate(x, y - _size);
getGlyphPositions(glyphs, matrix, flags, positioned_glyphs, positions);
QSize s(_size - 3, _size - 3);
for (int k = 0; k < positions.size(); k++)
path->addRect(QRectF(positions[k].toPointF(), s));
}
glyph_metrics_t QFontEngineBox::boundingBox(const QGlyphLayout &glyphs)
{
glyph_metrics_t overall;
overall.width = _size*glyphs.numGlyphs;
overall.height = _size;
overall.xoff = overall.width;
return overall;
}
void QFontEngineBox::draw(QPaintEngine *p, qreal x, qreal y, const QTextItemInt &ti)
{
if (!ti.glyphs.numGlyphs)
return;
// any fixes here should probably also be done in QPaintEnginePrivate::drawBoxTextItem
QSize s(_size - 3, _size - 3);
QVarLengthArray<QFixedPoint> positions;
QVarLengthArray<glyph_t> glyphs;
QTransform matrix = QTransform::fromTranslate(x, y - _size);
ti.fontEngine->getGlyphPositions(ti.glyphs, matrix, ti.flags, glyphs, positions);
if (glyphs.size() == 0)
return;
QPainter *painter = p->painter();
painter->save();
painter->setBrush(Qt::NoBrush);
QPen pen = painter->pen();
pen.setWidthF(lineThickness().toReal());
painter->setPen(pen);
for (int k = 0; k < positions.size(); k++)
painter->drawRect(QRectF(positions[k].toPointF(), s));
painter->restore();
}
glyph_metrics_t QFontEngineBox::boundingBox(glyph_t)
{
return glyph_metrics_t(0, -_size, _size, _size, _size, 0);
}
QFontEngine *QFontEngineBox::cloneWithSize(qreal pixelSize) const
{
QFontEngineBox *fe = new QFontEngineBox(pixelSize);
return fe;
}
QFixed QFontEngineBox::ascent() const
{
return _size;
}
QFixed QFontEngineBox::capHeight() const
{
return _size;
}
QFixed QFontEngineBox::descent() const
{
return 0;
}
QFixed QFontEngineBox::leading() const
{
QFixed l = _size * QFixed::fromReal(qreal(0.15));
return l.ceil();
}
qreal QFontEngineBox::maxCharWidth() const
{
return _size;
}
bool QFontEngineBox::canRender(const QChar *, int) const
{
return true;
}
QImage QFontEngineBox::alphaMapForGlyph(glyph_t)
{
QImage image(_size, _size, QImage::Format_Alpha8);
image.fill(0);
// FIXME: use qpainter
for (int i=2; i <= _size-3; ++i) {
image.setPixel(i, 2, 255);
image.setPixel(i, _size-3, 255);
image.setPixel(2, i, 255);
image.setPixel(_size-3, i, 255);
}
return image;
}
// ------------------------------------------------------------------
// Multi engine
// ------------------------------------------------------------------
static inline uchar highByte(glyph_t glyph)
{ return glyph >> 24; }
// strip high byte from glyph
static inline glyph_t stripped(glyph_t glyph)
{ return glyph & 0x00ffffff; }
QFontEngineMulti::QFontEngineMulti(QFontEngine *engine, int script, const QStringList &fallbackFamilies)
: QFontEngine(Multi),
m_fallbackFamilies(fallbackFamilies),
m_script(script),
m_fallbackFamiliesQueried(!m_fallbackFamilies.isEmpty())
{
Q_ASSERT(engine && engine->type() != QFontEngine::Multi);
if (m_fallbackFamilies.isEmpty()) {
// defer obtaining the fallback families until loadEngine(1)
m_fallbackFamilies << QString();
}
m_engines.resize(m_fallbackFamilies.size() + 1);
engine->ref.ref();
m_engines[0] = engine;
fontDef = engine->fontDef;
cache_cost = engine->cache_cost;
}
QFontEngineMulti::~QFontEngineMulti()
{
for (int i = 0; i < m_engines.size(); ++i) {
QFontEngine *fontEngine = m_engines.at(i);
if (fontEngine && !fontEngine->ref.deref())
delete fontEngine;
}
}
QStringList qt_fallbacksForFamily(const QString &family, QFont::Style style, QFont::StyleHint styleHint, QChar::Script script);
void QFontEngineMulti::ensureFallbackFamiliesQueried()
{
QFont::StyleHint styleHint = QFont::StyleHint(fontDef.styleHint);
if (styleHint == QFont::AnyStyle && fontDef.fixedPitch)
styleHint = QFont::TypeWriter;
setFallbackFamiliesList(qt_fallbacksForFamily(fontDef.family, QFont::Style(fontDef.style), styleHint, QChar::Script(m_script)));
}
void QFontEngineMulti::setFallbackFamiliesList(const QStringList &fallbackFamilies)
{
Q_ASSERT(!m_fallbackFamiliesQueried);
m_fallbackFamilies = fallbackFamilies;
if (m_fallbackFamilies.isEmpty()) {
// turns out we lied about having any fallback at all
Q_ASSERT(m_engines.size() == 2); // see c-tor for details
QFontEngine *engine = m_engines.at(0);
engine->ref.ref();
m_engines[1] = engine;
m_fallbackFamilies << fontDef.family;
} else {
m_engines.resize(m_fallbackFamilies.size() + 1);
}
m_fallbackFamiliesQueried = true;
}
void QFontEngineMulti::ensureEngineAt(int at)
{
if (!m_fallbackFamiliesQueried)
ensureFallbackFamiliesQueried();
Q_ASSERT(at < m_engines.size());
if (!m_engines.at(at)) {
QFontEngine *engine = loadEngine(at);
if (!engine)
engine = new QFontEngineBox(fontDef.pixelSize);
Q_ASSERT(engine && engine->type() != QFontEngine::Multi);
engine->ref.ref();
m_engines[at] = engine;
}
}
QFontEngine *QFontEngineMulti::loadEngine(int at)
{
QFontDef request(fontDef);
request.styleStrategy |= QFont::NoFontMerging;
request.family = fallbackFamilyAt(at - 1);
// At this point, the main script of the text has already been considered
// when fetching the list of fallback families from the database, and the
// info about the actual script of the characters may have been discarded,
// so we do not check for writing system support, but instead just load
// the family indiscriminately.
if (QFontEngine *engine = QFontDatabase::findFont(request, QChar::Script_Common)) {
engine->fontDef.weight = request.weight;
if (request.style > QFont::StyleNormal)
engine->fontDef.style = request.style;
return engine;
}
return 0;
}
glyph_t QFontEngineMulti::glyphIndex(uint ucs4) const
{
glyph_t glyph = engine(0)->glyphIndex(ucs4);
if (glyph == 0
&& ucs4 != QChar::LineSeparator
&& ucs4 != QChar::LineFeed
&& ucs4 != QChar::CarriageReturn
&& ucs4 != QChar::ParagraphSeparator) {
if (!m_fallbackFamiliesQueried)
const_cast<QFontEngineMulti *>(this)->ensureFallbackFamiliesQueried();
for (int x = 1, n = qMin(m_engines.size(), 256); x < n; ++x) {
QFontEngine *engine = m_engines.at(x);
if (!engine) {
if (!shouldLoadFontEngineForCharacter(x, ucs4))
continue;
const_cast<QFontEngineMulti *>(this)->ensureEngineAt(x);
engine = m_engines.at(x);
}
Q_ASSERT(engine != 0);
if (engine->type() == Box)
continue;
glyph = engine->glyphIndex(ucs4);
if (glyph != 0) {
// set the high byte to indicate which engine the glyph came from
glyph |= (x << 24);
break;
}
}
}
return glyph;
}
bool QFontEngineMulti::stringToCMap(const QChar *str, int len,
QGlyphLayout *glyphs, int *nglyphs,
QFontEngine::ShaperFlags flags) const
{
if (!engine(0)->stringToCMap(str, len, glyphs, nglyphs, flags))
return false;
int glyph_pos = 0;
QStringIterator it(str, str + len);
int lastFallback = -1;
while (it.hasNext()) {
const uint ucs4 = it.peekNext();
// If we applied a fallback font to previous glyph, and the current is either
// ZWJ or ZWNJ, we should also try applying the same fallback font to that, in order
// to get the correct shaping rules applied.
if (lastFallback >= 0 && (ucs4 == QChar(0x200d) || ucs4 == QChar(0x200c))) {
QFontEngine *engine = m_engines.at(lastFallback);
glyph_t glyph = engine->glyphIndex(ucs4);
if (glyph != 0) {
glyphs->glyphs[glyph_pos] = glyph;
if (!(flags & GlyphIndicesOnly)) {
QGlyphLayout g = glyphs->mid(glyph_pos, 1);
engine->recalcAdvances(&g, flags);
}
// set the high byte to indicate which engine the glyph came from
glyphs->glyphs[glyph_pos] |= (lastFallback << 24);
} else {
lastFallback = -1;
}
} else {
lastFallback = -1;
}
if (glyphs->glyphs[glyph_pos] == 0
&& ucs4 != QChar::LineSeparator
&& ucs4 != QChar::LineFeed
&& ucs4 != QChar::CarriageReturn
&& ucs4 != QChar::ParagraphSeparator) {
if (!m_fallbackFamiliesQueried)
const_cast<QFontEngineMulti *>(this)->ensureFallbackFamiliesQueried();
for (int x = 1, n = qMin(m_engines.size(), 256); x < n; ++x) {
QFontEngine *engine = m_engines.at(x);
if (!engine) {
if (!shouldLoadFontEngineForCharacter(x, ucs4))
continue;
const_cast<QFontEngineMulti *>(this)->ensureEngineAt(x);
engine = m_engines.at(x);
if (!engine)
continue;
}
Q_ASSERT(engine != 0);
if (engine->type() == Box)
continue;
glyph_t glyph = engine->glyphIndex(ucs4);
if (glyph != 0) {
glyphs->glyphs[glyph_pos] = glyph;
if (!(flags & GlyphIndicesOnly)) {
QGlyphLayout g = glyphs->mid(glyph_pos, 1);
engine->recalcAdvances(&g, flags);
}
lastFallback = x;
// set the high byte to indicate which engine the glyph came from
glyphs->glyphs[glyph_pos] |= (x << 24);
break;
}
}
}
it.advance();
++glyph_pos;
}
*nglyphs = glyph_pos;
glyphs->numGlyphs = glyph_pos;
return true;
}
bool QFontEngineMulti::shouldLoadFontEngineForCharacter(int at, uint ucs4) const
{
Q_UNUSED(at);
Q_UNUSED(ucs4);
return true;
}
glyph_metrics_t QFontEngineMulti::boundingBox(const QGlyphLayout &glyphs)
{
if (glyphs.numGlyphs <= 0)
return glyph_metrics_t();
glyph_metrics_t overall;
int which = highByte(glyphs.glyphs[0]);
int start = 0;
int end, i;
for (end = 0; end < glyphs.numGlyphs; ++end) {
const int e = highByte(glyphs.glyphs[end]);
if (e == which)
continue;
// set the high byte to zero
for (i = start; i < end; ++i)
glyphs.glyphs[i] = stripped(glyphs.glyphs[i]);
// merge the bounding box for this run
const glyph_metrics_t gm = engine(which)->boundingBox(glyphs.mid(start, end - start));
overall.x = qMin(overall.x, gm.x);
overall.y = qMin(overall.y, gm.y);
overall.width = overall.xoff + gm.width;
overall.height = qMax(overall.height + overall.y, gm.height + gm.y) -
qMin(overall.y, gm.y);
overall.xoff += gm.xoff;
overall.yoff += gm.yoff;
// reset the high byte for all glyphs
const int hi = which << 24;
for (i = start; i < end; ++i)
glyphs.glyphs[i] = hi | glyphs.glyphs[i];
// change engine
start = end;
which = e;
}
// set the high byte to zero
for (i = start; i < end; ++i)
glyphs.glyphs[i] = stripped(glyphs.glyphs[i]);
// merge the bounding box for this run
const glyph_metrics_t gm = engine(which)->boundingBox(glyphs.mid(start, end - start));
overall.x = qMin(overall.x, gm.x);
overall.y = qMin(overall.y, gm.y);
overall.width = overall.xoff + gm.width;
overall.height = qMax(overall.height + overall.y, gm.height + gm.y) -
qMin(overall.y, gm.y);
overall.xoff += gm.xoff;
overall.yoff += gm.yoff;
// reset the high byte for all glyphs
const int hi = which << 24;
for (i = start; i < end; ++i)
glyphs.glyphs[i] = hi | glyphs.glyphs[i];
return overall;
}
void QFontEngineMulti::getGlyphBearings(glyph_t glyph, qreal *leftBearing, qreal *rightBearing)
{
int which = highByte(glyph);
ensureEngineAt(which);
engine(which)->getGlyphBearings(stripped(glyph), leftBearing, rightBearing);
}
void QFontEngineMulti::addOutlineToPath(qreal x, qreal y, const QGlyphLayout &glyphs,
QPainterPath *path, QTextItem::RenderFlags flags)
{
if (glyphs.numGlyphs <= 0)
return;
int which = highByte(glyphs.glyphs[0]);
int start = 0;
int end, i;
if (flags & QTextItem::RightToLeft) {
for (int gl = 0; gl < glyphs.numGlyphs; gl++)
x += glyphs.advances[gl].toReal();
}
for (end = 0; end < glyphs.numGlyphs; ++end) {
const int e = highByte(glyphs.glyphs[end]);
if (e == which)
continue;
if (flags & QTextItem::RightToLeft) {
for (i = start; i < end; ++i)
x -= glyphs.advances[i].toReal();
}
// set the high byte to zero
for (i = start; i < end; ++i)
glyphs.glyphs[i] = stripped(glyphs.glyphs[i]);
engine(which)->addOutlineToPath(x, y, glyphs.mid(start, end - start), path, flags);
// reset the high byte for all glyphs and update x and y
const int hi = which << 24;
for (i = start; i < end; ++i)
glyphs.glyphs[i] = hi | glyphs.glyphs[i];
if (!(flags & QTextItem::RightToLeft)) {
for (i = start; i < end; ++i)
x += glyphs.advances[i].toReal();
}
// change engine
start = end;
which = e;
}
if (flags & QTextItem::RightToLeft) {
for (i = start; i < end; ++i)
x -= glyphs.advances[i].toReal();
}
// set the high byte to zero
for (i = start; i < end; ++i)
glyphs.glyphs[i] = stripped(glyphs.glyphs[i]);
engine(which)->addOutlineToPath(x, y, glyphs.mid(start, end - start), path, flags);
// reset the high byte for all glyphs
const int hi = which << 24;
for (i = start; i < end; ++i)
glyphs.glyphs[i] = hi | glyphs.glyphs[i];
}
void QFontEngineMulti::recalcAdvances(QGlyphLayout *glyphs, QFontEngine::ShaperFlags flags) const
{
if (glyphs->numGlyphs <= 0)
return;
int which = highByte(glyphs->glyphs[0]);
int start = 0;
int end, i;
for (end = 0; end < glyphs->numGlyphs; ++end) {
const int e = highByte(glyphs->glyphs[end]);
if (e == which)
continue;
// set the high byte to zero
for (i = start; i < end; ++i)
glyphs->glyphs[i] = stripped(glyphs->glyphs[i]);
QGlyphLayout offs = glyphs->mid(start, end - start);
engine(which)->recalcAdvances(&offs, flags);
// reset the high byte for all glyphs and update x and y
const int hi = which << 24;
for (i = start; i < end; ++i)
glyphs->glyphs[i] = hi | glyphs->glyphs[i];
// change engine
start = end;
which = e;
}
// set the high byte to zero
for (i = start; i < end; ++i)
glyphs->glyphs[i] = stripped(glyphs->glyphs[i]);
QGlyphLayout offs = glyphs->mid(start, end - start);
engine(which)->recalcAdvances(&offs, flags);
// reset the high byte for all glyphs
const int hi = which << 24;
for (i = start; i < end; ++i)
glyphs->glyphs[i] = hi | glyphs->glyphs[i];
}
void QFontEngineMulti::doKerning(QGlyphLayout *glyphs, QFontEngine::ShaperFlags flags) const
{
if (glyphs->numGlyphs <= 0)
return;
int which = highByte(glyphs->glyphs[0]);
int start = 0;
int end, i;
for (end = 0; end < glyphs->numGlyphs; ++end) {
const int e = highByte(glyphs->glyphs[end]);
if (e == which)
continue;
// set the high byte to zero
for (i = start; i < end; ++i)
glyphs->glyphs[i] = stripped(glyphs->glyphs[i]);
QGlyphLayout offs = glyphs->mid(start, end - start);
engine(which)->doKerning(&offs, flags);
// reset the high byte for all glyphs and update x and y
const int hi = which << 24;
for (i = start; i < end; ++i)
glyphs->glyphs[i] = hi | glyphs->glyphs[i];
// change engine
start = end;
which = e;
}
// set the high byte to zero
for (i = start; i < end; ++i)
glyphs->glyphs[i] = stripped(glyphs->glyphs[i]);
QGlyphLayout offs = glyphs->mid(start, end - start);
engine(which)->doKerning(&offs, flags);
// reset the high byte for all glyphs
const int hi = which << 24;
for (i = start; i < end; ++i)
glyphs->glyphs[i] = hi | glyphs->glyphs[i];
}
glyph_metrics_t QFontEngineMulti::boundingBox(glyph_t glyph)
{
const int which = highByte(glyph);
return engine(which)->boundingBox(stripped(glyph));
}
QFixed QFontEngineMulti::ascent() const
{ return engine(0)->ascent(); }
QFixed QFontEngineMulti::capHeight() const
{ return engine(0)->capHeight(); }
QFixed QFontEngineMulti::descent() const
{ return engine(0)->descent(); }
QFixed QFontEngineMulti::leading() const
{
return engine(0)->leading();
}
QFixed QFontEngineMulti::xHeight() const
{
return engine(0)->xHeight();
}
QFixed QFontEngineMulti::averageCharWidth() const
{
return engine(0)->averageCharWidth();
}
QFixed QFontEngineMulti::lineThickness() const
{
return engine(0)->lineThickness();
}
QFixed QFontEngineMulti::underlinePosition() const
{
return engine(0)->underlinePosition();
}
qreal QFontEngineMulti::maxCharWidth() const
{
return engine(0)->maxCharWidth();
}
qreal QFontEngineMulti::minLeftBearing() const
{
return engine(0)->minLeftBearing();
}
qreal QFontEngineMulti::minRightBearing() const
{
return engine(0)->minRightBearing();
}
bool QFontEngineMulti::canRender(const QChar *string, int len) const
{
if (engine(0)->canRender(string, len))
return true;
int nglyphs = len;
QVarLengthArray<glyph_t> glyphs(nglyphs);
QGlyphLayout g;
g.numGlyphs = nglyphs;
g.glyphs = glyphs.data();
if (!stringToCMap(string, len, &g, &nglyphs, GlyphIndicesOnly))
Q_UNREACHABLE();
for (int i = 0; i < nglyphs; i++) {
if (glyphs[i] == 0)
return false;
}
return true;
}
/* Implement alphaMapForGlyph() which is called by Lighthouse/Windows code.
* Ideally, that code should be fixed to correctly handle QFontEngineMulti. */
QImage QFontEngineMulti::alphaMapForGlyph(glyph_t glyph)
{
const int which = highByte(glyph);
return engine(which)->alphaMapForGlyph(stripped(glyph));
}
QImage QFontEngineMulti::alphaMapForGlyph(glyph_t glyph, QFixed subPixelPosition)
{
const int which = highByte(glyph);
return engine(which)->alphaMapForGlyph(stripped(glyph), subPixelPosition);
}
QImage QFontEngineMulti::alphaMapForGlyph(glyph_t glyph, const QTransform &t)
{
const int which = highByte(glyph);
return engine(which)->alphaMapForGlyph(stripped(glyph), t);
}
QImage QFontEngineMulti::alphaMapForGlyph(glyph_t glyph, QFixed subPixelPosition, const QTransform &t)
{
const int which = highByte(glyph);
return engine(which)->alphaMapForGlyph(stripped(glyph), subPixelPosition, t);
}
QImage QFontEngineMulti::alphaRGBMapForGlyph(glyph_t glyph, QFixed subPixelPosition, const QTransform &t)
{
const int which = highByte(glyph);
return engine(which)->alphaRGBMapForGlyph(stripped(glyph), subPixelPosition, t);
}
/*
This is used indirectly by Qt WebKit when using QTextLayout::setRawFont
The purpose of this is to provide the necessary font fallbacks when drawing complex
text. Since Qt WebKit ends up repeatedly creating QTextLayout instances and passing them
the same raw font over and over again, we want to cache the corresponding multi font engine
as it may contain fallback font engines already.
*/
QFontEngine *QFontEngineMulti::createMultiFontEngine(QFontEngine *fe, int script)
{
QFontEngine *engine = 0;
QFontCache::Key key(fe->fontDef, script, /*multi = */true);
QFontCache *fc = QFontCache::instance();
// We can't rely on the fontDef (and hence the cache Key)
// alone to distinguish webfonts, since these should not be
// accidentally shared, even if the resulting fontcache key
// is strictly identical. See:
// http://www.w3.org/TR/css3-fonts/#font-face-rule
const bool faceIsLocal = !fe->faceId().filename.isEmpty();
QFontCache::EngineCache::Iterator it = fc->engineCache.find(key),
end = fc->engineCache.end();
while (it != end && it.key() == key) {
Q_ASSERT(it.value().data->type() == QFontEngine::Multi);
QFontEngineMulti *cachedEngine = static_cast<QFontEngineMulti *>(it.value().data);
if (fe == cachedEngine->engine(0) || (faceIsLocal && fe->faceId().filename == cachedEngine->engine(0)->faceId().filename)) {
engine = cachedEngine;
fc->updateHitCountAndTimeStamp(it.value());
break;
}
++it;
}
if (!engine) {
engine = QGuiApplicationPrivate::instance()->platformIntegration()->fontDatabase()->fontEngineMulti(fe, QChar::Script(script));
fc->insertEngine(key, engine, /* insertMulti */ !faceIsLocal);
}
Q_ASSERT(engine);
return engine;
}
QTestFontEngine::QTestFontEngine(int size)
: QFontEngineBox(TestFontEngine, size)
{}
QT_END_NAMESPACE
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