graphicscontextqt.cpp

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void GraphicsContext::drawRect(const IntRect& rect)
{
    if (paintingDisabled())
        return;

    QPainter *p = m_data->p();
    const bool antiAlias = p->testRenderHint(QPainter::Antialiasing);
    p->setRenderHint(QPainter::Antialiasing, m_data->antiAliasingForRectsAndLines);

    p->drawRect(rect);

    p->setRenderHint(QPainter::Antialiasing, antiAlias);
}

// FIXME: Now that this is refactored, it should be shared by all contexts.
static void adjustLineToPixelBoundaries(FloatPoint& p1, FloatPoint& p2, float strokeWidth,
                                        const StrokeStyle& penStyle)
{
    // For odd widths, we add in 0.5 to the appropriate x/y so that the float arithmetic
    // works out.  For example, with a border width of 3, KHTML will pass us (y1+y2)/2, e.g.,
    // (50+53)/2 = 103/2 = 51 when we want 51.5.  It is always true that an even width gave
    // us a perfect position, but an odd width gave us a position that is off by exactly 0.5.
    if (penStyle == DottedStroke || penStyle == DashedStroke) {
        if (p1.x() == p2.x()) {
            p1.setY(p1.y() + strokeWidth);
            p2.setY(p2.y() - strokeWidth);
        } else {
            p1.setX(p1.x() + strokeWidth);
            p2.setX(p2.x() - strokeWidth);
        }
    }

    if (((int) strokeWidth) % 2) {
        if (p1.x() == p2.x()) {
            // We're a vertical line.  Adjust our x.
            p1.setX(p1.x() + 0.5);
            p2.setX(p2.x() + 0.5);
        } else {
            // We're a horizontal line. Adjust our y.
            p1.setY(p1.y() + 0.5);
            p2.setY(p2.y() + 0.5);
        }
    }
}

// This is only used to draw borders.
void GraphicsContext::drawLine(const IntPoint& point1, const IntPoint& point2)
{
    if (paintingDisabled())
        return;

    FloatPoint p1 = point1;
    FloatPoint p2 = point2;

    QPainter *p = m_data->p();
    const bool antiAlias = p->testRenderHint(QPainter::Antialiasing);
    p->setRenderHint(QPainter::Antialiasing, m_data->antiAliasingForRectsAndLines);
    adjustLineToPixelBoundaries(p1, p2, strokeThickness(), strokeStyle());

    IntSize shadowSize;
    int shadowBlur;
    Color shadowColor;
    if (textDrawingMode() == cTextFill && getShadow(shadowSize, shadowBlur, shadowColor)) {
        p->save();
        p->translate(shadowSize.width(), shadowSize.height());
        p->setPen(QColor(shadowColor));
        p->drawLine(p1, p2);
        p->restore();
    }

    p->drawLine(p1, p2);

    p->setRenderHint(QPainter::Antialiasing, antiAlias);
}

// This method is only used to draw the little circles used in lists.
void GraphicsContext::drawEllipse(const IntRect& rect)
{
    if (paintingDisabled())
        return;

    m_data->p()->drawEllipse(rect);
}

void GraphicsContext::strokeArc(const IntRect& rect, int startAngle, int angleSpan)
{
    if (paintingDisabled() || strokeStyle() == NoStroke || strokeThickness() <= 0.0f || !strokeColor().alpha())
        return;

    QPainter *p = m_data->p();
    const bool antiAlias = p->testRenderHint(QPainter::Antialiasing);
    p->setRenderHint(QPainter::Antialiasing, m_data->antiAliasingForRectsAndLines);

    p->drawArc(rect, startAngle * 16, angleSpan * 16);

    p->setRenderHint(QPainter::Antialiasing, antiAlias);
}

void GraphicsContext::drawConvexPolygon(size_t npoints, const FloatPoint* points, bool shouldAntialias)
{
    if (paintingDisabled())
        return;

    if (npoints <= 1)
        return;

    QPolygonF polygon(npoints);

    for (size_t i = 0; i < npoints; i++)
        polygon[i] = points[i];

    QPainter *p = m_data->p();
    p->save();
    p->setRenderHint(QPainter::Antialiasing, shouldAntialias);
    p->drawConvexPolygon(polygon);
    p->restore();
}

QPen GraphicsContext::pen()
{
    if (paintingDisabled())
        return QPen();

    QPainter *p = m_data->p();
    return p->pen();
}

void GraphicsContext::fillPath()
{
    if (paintingDisabled())
        return;

    QPainter *p = m_data->p();
    QPainterPath path = m_data->currentPath;

    switch (m_common->state.fillColorSpace) {
    case SolidColorSpace:
        if (fillColor().alpha())
            p->fillPath(path, p->brush());
        break;
    case PatternColorSpace: {
        TransformationMatrix affine;
        p->fillPath(path, QBrush(m_common->state.fillPattern->createPlatformPattern(affine)));
        break;
    }
    case GradientColorSpace:
        QBrush brush(*m_common->state.fillGradient->platformGradient());
        brush.setTransform(m_common->state.fillGradient->gradientSpaceTransform());
        p->fillPath(path, brush);
        break;
    }
    m_data->currentPath = QPainterPath();
}

void GraphicsContext::strokePath()
{
    if (paintingDisabled())
        return;

    QPainter *p = m_data->p();
    QPen pen = p->pen();
    QPainterPath path = m_data->currentPath;

    switch (m_common->state.strokeColorSpace) {
    case SolidColorSpace:
        if (strokeColor().alpha())
            p->strokePath(path, pen);
        break;
    case PatternColorSpace: {
        TransformationMatrix affine;
        pen.setBrush(QBrush(m_common->state.strokePattern->createPlatformPattern(affine)));
        p->setPen(pen);
        p->strokePath(path, pen);
        break;
    }
    case GradientColorSpace: {
        QBrush brush(*m_common->state.strokeGradient->platformGradient());
        brush.setTransform(m_common->state.strokeGradient->gradientSpaceTransform());
        pen.setBrush(brush);
        p->setPen(pen);
        p->strokePath(path, pen);
        break;
    }
    }
    m_data->currentPath = QPainterPath();
}

void GraphicsContext::fillRect(const FloatRect& rect)
{
    if (paintingDisabled())
        return;

    QPainter *p = m_data->p();

    switch (m_common->state.fillColorSpace) {
    case SolidColorSpace:
        if (fillColor().alpha())
            p->fillRect(rect, p->brush());
        break;
    case PatternColorSpace: {
        TransformationMatrix affine;
        p->fillRect(rect, QBrush(m_common->state.fillPattern->createPlatformPattern(affine)));
        break;
    }
    case GradientColorSpace:
        QBrush brush(*m_common->state.fillGradient->platformGradient());
        brush.setTransform(m_common->state.fillGradient->gradientSpaceTransform());
        p->fillRect(rect, brush);
        break;
    }
    m_data->currentPath = QPainterPath();
}

void GraphicsContext::fillRect(const FloatRect& rect, const Color& c)
{
    if (paintingDisabled())
        return;

    m_data->solidColor.setColor(QColor(c));
    m_data->p()->fillRect(rect, m_data->solidColor);
}

void GraphicsContext::fillRoundedRect(const IntRect& rect, const IntSize& topLeft, const IntSize& topRight, const IntSize& bottomLeft, const IntSize& bottomRight, const Color& color)
{
    if (paintingDisabled() || !color.alpha())
        return;

    Path path = Path::createRoundedRectangle(rect, topLeft, topRight, bottomLeft, bottomRight);
    m_data->p()->fillPath(*path.platformPath(), QColor(color));
}

void GraphicsContext::beginPath()
{
    m_data->currentPath = QPainterPath();
}

void GraphicsContext::addPath(const Path& path)
{
    QPainterPath newPath = m_data->currentPath;
    newPath.addPath(*(path.platformPath()));
    m_data->currentPath = newPath;
}

bool GraphicsContext::inTransparencyLayer() const
{
    return !m_data->layers.isEmpty();
}

PlatformPath* GraphicsContext::currentPath()
{
    return &m_data->currentPath;
}

void GraphicsContext::clip(const FloatRect& rect)
{
    if (paintingDisabled())
        return;

    m_data->p()->setClipRect(rect, Qt::IntersectClip);
}

void GraphicsContext::clipPath(WindRule clipRule)
{
    if (paintingDisabled())
        return;

    QPainter *p = m_data->p();
    QPainterPath newPath = m_data->currentPath;
    newPath.setFillRule(clipRule == RULE_EVENODD ? Qt::OddEvenFill : Qt::WindingFill);
    p->setClipPath(newPath);
}

/**
 * Focus ring handling is not handled here. Qt style in 
 * RenderTheme handles drawing focus on widgets which 
 * need it.
 */
Color focusRingColor() { return Color(0, 0, 0); }
void GraphicsContext::drawFocusRing(const Color& color)
{
    if (paintingDisabled())
        return;

    const Vector<IntRect>& rects = focusRingRects();
    unsigned rectCount = rects.size();

    if (rects.size() == 0)
        return;

    QPainter *p = m_data->p();
    const bool antiAlias = p->testRenderHint(QPainter::Antialiasing);
    p->setRenderHint(QPainter::Antialiasing, m_data->antiAliasingForRectsAndLines);

    const QPen oldPen = p->pen();
    const QBrush oldBrush = p->brush();

    QPen nPen = p->pen();
    nPen.setColor(color);
    p->setBrush(Qt::NoBrush);
    nPen.setStyle(Qt::DotLine);
    p->setPen(nPen);
#if 0
    // FIXME How do we do a bounding outline with Qt?
    QPainterPath path;
    for (int i = 0; i < rectCount; ++i)
        path.addRect(QRectF(rects[i]));
    QPainterPathStroker stroker;
    QPainterPath newPath = stroker.createStroke(path);
    p->strokePath(newPath, nPen);
#else
    for (int i = 0; i < rectCount; ++i)
        p->drawRect(QRectF(rects[i]));
#endif
    p->setPen(oldPen);
    p->setBrush(oldBrush);

    p->setRenderHint(QPainter::Antialiasing, antiAlias);
}

void GraphicsContext::drawLineForText(const IntPoint& origin, int width, bool printing)
{
    if (paintingDisabled())
        return;

    IntPoint endPoint = origin + IntSize(width, 0);
    drawLine(origin, endPoint);
}

void GraphicsContext::drawLineForMisspellingOrBadGrammar(const IntPoint&,
                                                         int width, bool grammar)
{
    if (paintingDisabled())
        return;

    notImplemented();
}

FloatRect GraphicsContext::roundToDevicePixels(const FloatRect& frect)
{
    QRectF rect(frect);
    rect = m_data->p()->deviceMatrix().mapRect(rect);

    QRect result = rect.toRect(); //round it
    return FloatRect(QRectF(result));
}

void GraphicsContext::setPlatformShadow(const IntSize& pos, int blur, const Color &color)
{
    // Qt doesn't support shadows natively, they are drawn manually in the draw*
    // functions
}

void GraphicsContext::clearPlatformShadow()
{
    // Qt doesn't support shadows natively, they are drawn manually in the draw*
    // functions
}

void GraphicsContext::beginTransparencyLayer(float opacity)
{
    if (paintingDisabled())
        return;

    int x, y, w, h;
    x = y = 0;
    QPainter *p = m_data->p();
    const QPaintDevice *device = p->device();
    w = device->width();
    h = device->height();

    QRectF clip = p->clipPath().boundingRect();
    QRectF deviceClip = p->transform().mapRect(clip);
    x = int(qBound(qreal(0), deviceClip.x(), (qreal)w));
    y = int(qBound(qreal(0), deviceClip.y(), (qreal)h));
    w = int(qBound(qreal(0), deviceClip.width(), (qreal)w) + 2);
    h = int(qBound(qreal(0), deviceClip.height(), (qreal)h) + 2);

    TransparencyLayer * layer = new TransparencyLayer(m_data->p(), QRect(x, y, w, h));

    layer->opacity = opacity;
    m_data->layers.push(layer);
}

void GraphicsContext::endTransparencyLayer()
{
    if (paintingDisabled())
        return;

    TransparencyLayer *layer = m_data->layers.pop();
    layer->painter.end();

    QPainter *p = m_data->p();
    p->save();
    p->resetTransform();
    p->setOpacity(layer->opacity);
    p->drawPixmap(layer->offset, layer->pixmap);
    p->restore();