/*
Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
Copyright (C) 2008, 2010 Holger Hans Peter Freyther
Copyright (C) 2009 Dirk Schulze <krit@webkit.org>
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public License
along with this library; see the file COPYING.LIB. If not, write to
the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA.
*/
#include "config.h"
#include "Font.h"
#include "AffineTransform.h"
#include "FontDescription.h"
#include "FontFallbackList.h"
#include "FontSelector.h"
#include "Gradient.h"
#include "GraphicsContext.h"
#include "Pattern.h"
#include <QBrush>
#include <QFontInfo>
#include <QFontMetrics>
#include <QPainter>
#include <QPainterPath>
#include <QPen>
#include <QTextLayout>
#include <qalgorithms.h>
#include <qdebug.h>
#include <limits.h>
namespace WebCore {
static const QString fromRawDataWithoutRef(const String& string, int start = 0, int len = -1)
{
if (len < 0)
len = string.length() - start;
Q_ASSERT(start + len <= string.length());
// We don't detach. This assumes the WebCore string data will stay valid for the
// lifetime of the QString we pass back, since we don't ref the WebCore string.
return QString::fromRawData(reinterpret_cast<const QChar*>(string.characters() + start), len);
}
static QTextLine setupLayout(QTextLayout* layout, const TextRun& style)
{
int flags = style.rtl() ? Qt::TextForceRightToLeft : Qt::TextForceLeftToRight;
if (style.padding())
flags |= Qt::TextJustificationForced;
layout->setFlags(flags);
layout->beginLayout();
QTextLine line = layout->createLine();
line.setLineWidth(INT_MAX/256);
if (style.padding())
line.setLineWidth(line.naturalTextWidth() + style.padding());
layout->endLayout();
return line;
}
static void drawTextCommon(GraphicsContext* ctx, const TextRun& run, const FloatPoint& point, int from, int to, const QFont& font, bool isComplexText)
{
if (to < 0)
to = run.length();
QPainter *p = ctx->platformContext();
QPen textFillPen;
if (ctx->textDrawingMode() & cTextFill) {
if (ctx->fillGradient()) {
QBrush brush(*ctx->fillGradient()->platformGradient());
brush.setTransform(ctx->fillGradient()->gradientSpaceTransform());
textFillPen = QPen(brush, 0);
} else if (ctx->fillPattern()) {
AffineTransform affine;
textFillPen = QPen(QBrush(ctx->fillPattern()->createPlatformPattern(affine)), 0);
} else
textFillPen = QPen(QColor(ctx->fillColor()));
}
QPen textStrokePen;
if (ctx->textDrawingMode() & cTextStroke) {
if (ctx->strokeGradient()) {
QBrush brush(*ctx->strokeGradient()->platformGradient());
brush.setTransform(ctx->strokeGradient()->gradientSpaceTransform());
textStrokePen = QPen(brush, ctx->strokeThickness());
} else if (ctx->strokePattern()) {
AffineTransform affine;
QBrush brush(ctx->strokePattern()->createPlatformPattern(affine));
textStrokePen = QPen(brush, ctx->strokeThickness());
} else
textStrokePen = QPen(QColor(ctx->strokeColor()), ctx->strokeThickness());
}
String sanitized = Font::normalizeSpaces(String(run.characters(), run.length()));
QString string = fromRawDataWithoutRef(sanitized);
QPointF pt(point.x(), point.y());
// text shadow
FloatSize shadowSize;
float shadowBlur;
Color shadowColor;
bool hasShadow = ctx->textDrawingMode() == cTextFill && ctx->getShadow(shadowSize, shadowBlur, shadowColor);
if (from > 0 || to < run.length()) {
if (isComplexText) {
QTextLayout layout(string, font);
QTextLine line = setupLayout(&layout, run);
float x1 = line.cursorToX(from);
float x2 = line.cursorToX(to);
if (x2 < x1)
qSwap(x1, x2);
QFontMetrics fm(font);
int ascent = fm.ascent();
QRectF clip(point.x() + x1, point.y() - ascent, x2 - x1, fm.height());
if (hasShadow) {
// TODO: when blur support is added, the clip will need to account
// for the blur radius
qreal dx1 = 0, dx2 = 0, dy1 = 0, dy2 = 0;
if (shadowSize.width() > 0)
dx2 = shadowSize.width();
else
dx1 = -shadowSize.width();
if (shadowSize.height() > 0)
dy2 = shadowSize.height();
else
dy1 = -shadowSize.height();
// expand the clip rect to include the text shadow as well
clip.adjust(dx1, dx2, dy1, dy2);
}
p->save();
p->setClipRect(clip.toRect(), Qt::IntersectClip);
pt.setY(pt.y() - ascent);
if (hasShadow) {
p->save();
p->setPen(QColor(shadowColor));
p->translate(shadowSize.width(), shadowSize.height());
line.draw(p, pt);
p->restore();
}
p->setPen(textFillPen);
line.draw(p, pt);
p->restore();
return;
}
#if QT_VERSION >= QT_VERSION_CHECK(4, 7, 0)
int skipWidth = QFontMetrics(font).width(string, from, Qt::TextBypassShaping);
pt.setX(pt.x() + skipWidth);
string = fromRawDataWithoutRef(sanitized, from, to - from);
#endif
}
p->setFont(font);
int flags = run.rtl() ? Qt::TextForceRightToLeft : Qt::TextForceLeftToRight;
#if QT_VERSION >= QT_VERSION_CHECK(4, 7, 0)
// See QWebPagePrivate::QWebPagePrivate() where the default path is set to Complex for Qt 4.6 and earlier.
if (!isComplexText && !(ctx->textDrawingMode() & cTextStroke))
flags |= Qt::TextBypassShaping;
#endif
if (hasShadow) {
// TODO: text shadow blur support
p->save();
p->setPen(QColor(shadowColor));
p->translate(shadowSize.width(), shadowSize.height());
p->drawText(pt, string, flags, run.padding());
p->restore();
}
if (ctx->textDrawingMode() & cTextStroke) {
QPainterPath path;
path.addText(pt, font, string);
p->setPen(textStrokePen);
p->strokePath(path, p->pen());
}
if (ctx->textDrawingMode() & cTextFill) {
p->setPen(textFillPen);
p->drawText(pt, string, flags, run.padding());
}
}
void Font::drawSimpleText(GraphicsContext* ctx, const TextRun& run, const FloatPoint& point, int from, int to) const
{
#if QT_VERSION >= QT_VERSION_CHECK(4, 7, 0)
drawTextCommon(ctx, run, point, from, to, font(), /* isComplexText = */false);
#else
Q_ASSERT(false);
#endif
}
void Font::drawComplexText(GraphicsContext* ctx, const TextRun& run, const FloatPoint& point, int from, int to) const
{
drawTextCommon(ctx, run, point, from, to, font(), /* isComplexText = */true);
}
float Font::floatWidthForSimpleText(const TextRun& run, GlyphBuffer* glyphBuffer, HashSet<const SimpleFontData*>* fallbackFonts, GlyphOverflow* glyphOverflow) const
{
#if QT_VERSION >= QT_VERSION_CHECK(4, 7, 0)
if (!run.length())
return 0;
String sanitized = Font::normalizeSpaces(String(run.characters(), run.length()));
QString string = fromRawDataWithoutRef(sanitized);
int w = QFontMetrics(font()).width(string, -1, Qt::TextBypassShaping);
// WebKit expects us to ignore word spacing on the first character (as opposed to what Qt does)
if (treatAsSpace(run[0]))
w -= m_wordSpacing;
return w + run.padding();
#else
Q_ASSERT(false);
return 0.0f;
#endif
}
float Font::floatWidthForComplexText(const TextRun& run, HashSet<const SimpleFontData*>*, GlyphOverflow*) const
{
if (!run.length())
return 0;
if (run.length() == 1 && treatAsSpace(run[0]))
return QFontMetrics(font()).width(space) + run.padding();
String sanitized = Font::normalizeSpaces(String(run.characters(), run.length()));
QString string = fromRawDataWithoutRef(sanitized);
int w = QFontMetrics(font()).width(string);
// WebKit expects us to ignore word spacing on the first character (as opposed to what Qt does)
if (treatAsSpace(run[0]))
w -= m_wordSpacing;
return w + run.padding();
}
int Font::offsetForPositionForSimpleText(const TextRun& run, float position, bool includePartialGlyphs) const
{
#if QT_VERSION >= QT_VERSION_CHECK(4, 7, 0)
String sanitized = Font::normalizeSpaces(String(run.characters(), run.length()));
QString string = fromRawDataWithoutRef(sanitized);
QFontMetrics fm(font());
float delta = position;
int curPos = 0;
do {
float charWidth = fm.width(string[curPos]);
delta -= charWidth;
if (includePartialGlyphs) {
if (delta + charWidth / 2 <= 0)
break;
} else {
if (delta + charWidth <= 0)
break;
}
} while (++curPos < string.size());
return curPos;
#else
Q_ASSERT(false);
return 0;
#endif
}
int Font::offsetForPositionForComplexText(const TextRun& run, float position, bool) const
{
String sanitized = Font::normalizeSpaces(String(run.characters(), run.length()));
QString string = fromRawDataWithoutRef(sanitized);
QTextLayout layout(string, font());
QTextLine line = setupLayout(&layout, run);
return line.xToCursor(position);
}
FloatRect Font::selectionRectForSimpleText(const TextRun& run, const FloatPoint& pt, int h, int from, int to) const
{
#if QT_VERSION >= QT_VERSION_CHECK(4, 7, 0)
String sanitized = Font::normalizeSpaces(String(run.characters(), run.length()));
QString wholeText = fromRawDataWithoutRef(sanitized);
QString selectedText = fromRawDataWithoutRef(sanitized, from, to - from);
int startX = QFontMetrics(font()).width(wholeText, from, Qt::TextBypassShaping);
int width = QFontMetrics(font()).width(selectedText, -1, Qt::TextBypassShaping);
return FloatRect(pt.x() + startX, pt.y(), width, h);
#else
Q_ASSERT(false);
return FloatRect();
#endif
}
FloatRect Font::selectionRectForComplexText(const TextRun& run, const FloatPoint& pt, int h, int from, int to) const
{
String sanitized = Font::normalizeSpaces(String(run.characters(), run.length()));
QString string = fromRawDataWithoutRef(sanitized);
QTextLayout layout(string, font());
QTextLine line = setupLayout(&layout, run);
float x1 = line.cursorToX(from);
float x2 = line.cursorToX(to);
if (x2 < x1)
qSwap(x1, x2);
return FloatRect(pt.x() + x1, pt.y(), x2 - x1, h);
}
bool Font::canReturnFallbackFontsForComplexText()
{
return false;
}
QFont Font::font() const
{
QFont f = primaryFont()->getQtFont();
if (m_letterSpacing != 0)
f.setLetterSpacing(QFont::AbsoluteSpacing, m_letterSpacing);
if (m_wordSpacing != 0)
f.setWordSpacing(m_wordSpacing);
return f;
}
}